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  1. It would seem that an increased energy retention in an H2O phase state modulated system, such as the Earth, can result in greater observed temperature differentials (and more kinetic activity and extrema in general) without necessarily raising the average measured surface temperature all that much, especially in brief geologic time periods (before Oceans fully respond, etc).

    ENSO has been proposed as a self-regulator of temperature that increases in convective activity in response to temperature differential. For example, see The Diabatic and Nonlinear Aspects of the El Nino-Southern Oscillation: Implications for its Past and Future Behavior (Sun 2009). Perhaps it is altogether possible that the actual climate sensitivity of the Earth is greater than currently proposed as feedbacks such as increased convective cooling, as well as cloud mediated reflective aerosol cooling reduces surface temperatures in a limited response range. Moreover, at some point of greater perturbation and forcing, new energy relationships will emerge and a gross change in average temperature will be observed.

    So bandying about theories of temperature regulation to dismiss concerns of anthropogenic climate change isill advised; critical biological systems stand at great risk, such as the carbon dioxide oxygen plankton cycle. Like other large scale perturbations in systems, climate forcing is certain to unfold in ecological and biological systems in very surprising ways as unknown limits are passed beyond a point of no return in human time scales…

    Life forms, and their intrinsic ecological feedback webs seem adapt a predictable range of climate periodicity and extremes in a limited range that once exceeded results in extinction; humans and our dependencies are no exception. It would seem a conservative prudent approach, and a change in our ways as a specie is in order…

    Comment by Jim Redden — 15 May 2010 @ 10:55 AM

  2. Hey, finally a science article again from the webs leading AGW site. What a relief, I was going to stop coming here if the last couple months kept up.

    It’s pretty relevant as far as I am concerned. The modeling is a sore point in my view, both the over-confidence in them by the media and the more “committed” followers of CAGW.

    Performance of the models going forward is the key obstacle to bringing in the more technically minded skeptics in the public IMO. Back-casting performance isn’t very interesting when the models are tuned as they are, although I certainly recognize how important back casting is to creating the model.

    I’ve brought this up before here, but I have watched hurricane season forecasts closely for over a decade here in FL, and it still is effectively a random number generator, devoid of skill. I’m not equating these two technologies, only the futile early attempts on prediction of these complex physical interactions.

    So I have no more confidence in climate prediction then these other forecasts, and when yet another model run shows “it’s worse then we thought”, it has zero impact on me. These type of articles are much more useful.

    Unfortunately for everyone, these things take decades to prove out and the model iteration rate is very slow with new data. Lack of accurate data other than temperature going back hundreds of years makes this even more difficult, and error prone.

    You can use the d-word for me if you like, but I totally support the modeling efforts as they could be very useful when they are proven accurate, particualarly on the regional basis.

    [Response: I would by no means disagree that a model prediction saying "it's worse than we thought' is meaningless. On the other hand, to the extent that any of us at RC have used this sort of phrase (if we ever have) it is in response to observations of phenomena (such as sea level rise) that are greater than the models have predicted, not the other way around as you imply. As for model we, and the IPCC, have always been careful to use 'projection' to avoid the impression that a prediction is being made. Projections are about ranges of possibility (sometimes with likelihoods attached, but still very much model-dependent and explicitly so). I would agree with you that the mainstream media, the deniers, and yes, some scientists confuse these issues quite badly.--eric]

    Comment by Tom S — 15 May 2010 @ 11:03 AM

  3. “…. relatively mild in the 900s to 1300s interval ( sometimes termed the “Medieval Warm Period”). But the spatial reconstructions reveal, however, why such global terms can be quite misleading, and why alternative phrases such as the “Medieval Climate Anomaly” are being increasingly favored by the community.”

    The “MCA” (Medieval Climate Anomaly) could mean that, rather than a CO2 driven AGW, we could be experiencing a “Modern Climate Anomaly” of 300+ years.

    We got another 150 years to go without having to blame CO2.

    [Response: If and when you can show that the "MCA" was globally similar to the current warming in its spatial pattern (which no one has any evidence for), and when you can show that the MCA was entirely due to internal variability (which might be right, but certainly isn't proven), then you will begin to have a point. Until then, don't fall into the trap that just because anthropogenic CO2 can't have been the cause of previous climate anomalies, it can't matter now. Think about it! Do you think that because previous market crashes have happened, the recent market crash can't be due to subprime mortgages (which didn't exist in the 30s, after all!).--eric]

    Comment by Anne — 15 May 2010 @ 11:34 AM

  4. Discussion of medieval and early modern CO2 levels was censored in another thread this week because it was off-topic. Perhaps Mike will accomodate it.

    There is an 7.9 ppm swing between the second-highest (MWP) and second-lowest (LIA) readings of the Law Dome CO2 concentrations. I discarded the highest and lowest readings because I figured they might be flukes.
    Assuming for the sake of the argument that this swing was caused by a fall in global temperatures and using the median carbon cycle sensitivity value from the Frank et al. recent Nature letter, a 1.03 C global cooling would be implied.
    Surely this very crude approach of mine can only be a first approximation at best. I imagine that only a fraction of these 8 ppm can reasonably be explained by the temperature changes but on the other hand I assume that there was not enough time for the full impact of the cooling to be reflected in CO2 concentrations. I also imagine that the regional variations Mike emphasized might well be more relevant than global average. I would nevertheless be interested in Mike’s opinion: would a 1C global cooling (with a huge uncertainty) between the extremes of the MWP and the LIA be more or less coherent with the temperature record?

    Comment by Anonymous Coward — 15 May 2010 @ 11:52 AM

  5. When this is done, people usually find that while it was relatively cool in global mean temperatures from the 1400s to the 1800s known as the “Little Ice Age” and relatively mild in the 900s to 1300s interval ( sometimes termed the “Medieval Warm Period”).

    I wonder what your opinion is of the obvious variance loss caused by your EIV and CPS style regression methods?

    Since the loss is known both at blogs and literature to reduce historic signal in comparison to the calibration period, wouldn’t uncertainty be the wrong word to use?

    [Response: I'll assume you're simply unaware of the fact that extensive tests of precisely this issue were provided in the previous article by Mann et al (2008) (covered by RealClimate previously) which used both "RegEM with TTLS" and "CPS" to reconstruct hemispheric mean temperatures. Tests were provided in the Supplemental Information of that article for both of the methods used, under conditions that closely emulate the situations encountered with the actual proxy data at hand. More extensive tests have been the subject of a number of previous papers referenced therein. The tests indicate that low-frequency variance loss is likely to be minimal in both cases, and particularly with RegEM with TTLS which is designed, like other similar methods that have been developed for this problem (see e.g. Hegerl et al (2006)), precisely to deal with that very issue. As the technical issues have been dealt with in this previous work, and are not the focus of this current post--which is addressing issues regarding the regional patterns of past variability and the factors that may explain them--all similar comments rehashing this and related talking points, will be considered OT. Lets keep the discussion on the topic at hand, and the scientifically-interesting issues that remain to be resolved. -mike]

    Comment by Jeff Id — 15 May 2010 @ 11:56 AM

  6. The “MCA” (Medieval Climate Anomaly) could mean that, rather than a CO2 driven AGW, we could be experiencing a “Modern Climate Anomaly” of 300+ years. We got another 150 years to go without having to blame CO2.
    Anne, that might be the case if there were not an adequate understanding of the natural forcings (levels of solar activity and vulcanism) causing the MCA and of anthropogenic forcings (greenhouse gases) largely causing what you call the Modern Climate Anomaly.

    Comment by Byron Smith — 15 May 2010 @ 11:59 AM

  7. To Tom S (#2)

    I would like to echo your comment on the fact that it is very welcome to have an actual science article here. I, too, am tiring of political battles and would like to learn more about Climate Science.

    I would, however, like to point out that the “it’s worse than we thought” projections start out by noting that the current measurements of the variables that effect climate are currently at the worse case projections of the latest IPCC forecasts. Thus it really is “worse than we thought” a few years ago — not based on models but rather based on actual measurements.

    Second, it has been point out many times a major difference in forecasting weather and forecasting climate.

    With climate forecasting we are looking at average climate over a period of time. For example, what will be the average temperature of the earth during the decade 2100-2109? And we can make these predictions with relative accuracy based on the amount of GHGs man puts into the air between now and then (that is an unknown since it is not science but rather policy.) And these projections are based on physics.

    On the other-hand, I can understand that you would like to know exactly (say to the hour) when a hurricane would hit, where it would hit, and how strong it will be. And you would like to have this information several days out. And, as you point out, that is not within the capability of weather forecasting at this time.

    Comment by AlCrawford — 15 May 2010 @ 12:19 PM

  8. Anne, for your possibility to be true, the climate sensitivity would need to be low – which, if I understand the science correctly, would be contradictory with the changes in climate during the LIA.

    It is important to understand the causes for changes in past climate so we can anticipate the changes due to a higher CO2 forcing.

    Very welcome post, BTW. It is good to read about the context of the 2009 Mann, et al. paper.

    Comment by Deech56 — 15 May 2010 @ 12:23 PM

  9. 2 Tom says, “You can use the d-word for me if you like, but I totally support the modeling efforts as they could be very useful when they are proven accurate, particualarly on the regional basis.”

    and 3 Anne says, “We got another 150 years to go without having to blame CO2.”

    You’re both setting up impossible standards. If AGW is sound, there is no time to waste. Prudence says to leave something alone when it may bite. You’re inverting the philosophy of prudence, which says to stop adding CO2 as quickly as can be done practically, until/if we know CO2 is “benign”.

    Comment by RichardC — 15 May 2010 @ 12:31 PM

  10. There have been several papers published on an alternative explanation to the solar forcing – volcanism model for the Little Ice Age – namely, a terrestrial carbon uptake model based on the depopulating effects of the black plague in Europe and smallpox in the Americas:

    Europe’s “Little Ice Age” may have been triggered by the 14th Century Black Death plague, BBC, 2006

    Dr Thomas van Hoof and his colleagues studied pollen grains and leaf remains collected from lake-bed sediments in the southeast Netherlands. Monitoring the ups and downs in abundance of cereal pollen (like buckwheat) and tree pollen (like birch and oak) enabled them to estimate changes in land-use between AD 1000 and 1500.

    There were a few objections – one, that the changes in carbon emissions and uptake were too small to make a real difference – however, the same argument also applies to solar forcing and volcanism. There are other effects of reforestation that can alter temperatures, as well – reduced albedo, cooler soil temperatures, etc. – particularly over several centuries.

    It’s possible that the ocean would have equilibrated with atmospheric CO2, reducing the effect. However, there could have been a significant lag time (say, 300 years?) There are also indications that similar pandemics in America played a collaborative role, meaning that it wasn’t only European carbon uptake:

    New World Post-Pandemic Reforestation Helped Start Little Ice Age, Say Scientists
    Dec. 19, 2008

    They concluded that reforestation of agricultural lands—abandoned as the population collapsed—pulled so much carbon out of the atmosphere that it helped trigger a period of global cooling, at its most intense from approximately 1500 to 1750, known as the Little Ice Age.

    “We estimate that the amount of carbon sequestered in the growing forests was about 10 to 50 percent of the total carbon that would have needed to come out of the atmosphere and oceans at that time to account for the observed changes in carbon dioxide concentrations,” said Richard Nevle, visiting scholar in the Department of Geological and Environmental Sciences at Stanford.

    Hence, carbon-cycle feedbacks linked to biological activity appear to have played at least some role in the climate variations of the past thousand years. Predicting how such feedbacks will play out in the next 300 years will certainly require good predictions of regional climate change – not just temperature, but also precipitation, snow pack, soil moisture, etc.

    Only by including carbon cycle feedbacks and longer time periods than 100 years in your projections can you come up with realistic long-term temperature estimates. So, you have to take the carbon cycle into account – hence, if the model ignores the carbon cycle effects…

    We interpret the resulting reconstructions in the context of results from climate model simulations forced by estimated past changes in natural (solar and volcanic) radiative forcing. – Mann et al. 2009

    Shouldn’t you at least take a look at forcing those models with plausible shifts in atmospheric carbon (not only in CO2, but also in black carbon from fires) due to a human population crash and associated reforestation? It’d be nice to see some kind of model-based estimate of the possible effect.

    [Response: Very unlikely scenario--CO2 didn't vary more than a few ppm over that time period, and the amount of land cover change possible at the time (minimal) is in concert with that. Further, albedo generally goes down with increasing tree cover, not up, albeit countered by evapotranspirational increases.--Jim]

    Comment by Ike Solem — 15 May 2010 @ 12:31 PM

  11. Tom S 2: Back-casting performance isn’t very interesting when the models are tuned as they are…

    BPL: Precisely how do you believe the models are “tuned?”

    Comment by Barton Paul Levenson — 15 May 2010 @ 2:19 PM

  12. Anne 4: The “MCA” (Medieval Climate Anomaly) could mean that, rather than a CO2 driven AGW, we could be experiencing a “Modern Climate Anomaly” of 300+ years.
    We got another 150 years to go without having to blame CO2.

    BPL: It’s called “radiation physics,” Anne. You might want to research it. There are physical reasons for thinking CO2 is responsible. The theory is not based on correlations in climate data.

    Comment by Barton Paul Levenson — 15 May 2010 @ 2:21 PM

  13. Anne 3, I meant, not 4. Sorry.

    Question for the scientists: if it were to be discovered that volcanic aerosols make the spread of drought worse, but industrial aerosols slow it down, what would account for the difference? What is different in the effects of the two?

    Comment by Barton Paul Levenson — 15 May 2010 @ 2:25 PM

  14. Ike (#10),
    Law Dome CO2 concentrations peaked before the “black death”, which is not to say it had no effect but it was no trigger. The temperature reconstructions I’ve seen (no doubt a small subset, and possibly not representative) peak centuries earlier.
    This event has been given unreasonable weight by the way. It took place during a protracted period of high mortality in many regions of Europe. This, and not a single disease, explains the demographic setback. So it’s more likely (though very speculative) that climate change caused chronic famines and therefore the “black death”.

    Note that, going by the ice cores, the fall in CO2 concentration between the MWP and the LIA was quite small. It’s not much of a forcing compared to the circulation changes described in Mike’s post.

    Comment by Anonymous Coward — 15 May 2010 @ 2:27 PM

  15. 9 Ike Solem: That is very interesting, but the Black Plague Hypothesis implies an enormous and local sensitivity. If it is right, we are in much deeper trouble than the deep trouble we thought we were in. Problem: CO2 effects couldn’t be limited to regions. CO2 disperses worldwide. I would like to hear from RealClimate people on that.

    3 Anne: NO!!! Too dangerous! We can’t take chances that might result in the extinction of the human race.

    RC: Thanks much. I downloaded the Guiot et al paper.

    I am on page 122 of “Storms of My Grandchildren” by Jim Hansen. I strongly recommend this as a popular book. Are there climate textbooks to download for free?

    Comment by Edward Greisch — 15 May 2010 @ 2:47 PM

  16. > Edward Greisch
    > plague … implies an enormous and local sensitivity

    Doesn’t make sense. CO2 is well mixed over a relatively short time.
    If you infer local sensitivity, what’s your basis for the inference?

    Comment by Hank Roberts — 15 May 2010 @ 3:15 PM

  17. Mike — Very clear. Thank you.

    Comment by David B. Benson — 15 May 2010 @ 4:52 PM

  18. “What a relief, I was going to stop coming here if the last couple months kept up.”

    Whew, we dodged a bullet there, guys…

    Comment by Completely Fed Up — 15 May 2010 @ 5:16 PM

  19. From the 75 year smoothed data in
    ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/law/law_co2.txt
    CO2 concentration varies over the intervals in question:
    1010 AD 279.5
    1185 AD 284.0
    1250 AD 281.9
    1330 AD 283.1
    1395 AD 280.3
    1440 AD 280.9
    1465 AD 280.6
    1530 AD 283.2
    1630 AD 275.6
    1730 AD 277.0
    1850 AD 285.2

    Comment by David B. Benson — 15 May 2010 @ 5:23 PM

  20. 1) An issue of The Holocene coming out later this year will have a bunch of papers relevant to this.

    2) Here’s a Law Dome CO2 plot.

    The chart shows 500 years where CO2 jiggles around ~280:284. Even allowing for the uncertainty of dates, *something* odd clearly happened in 30-50 years (~1570-1604 plotted dates) to drop CO2 sharply, and it didn’t return back to the 1000AD-1570AD range for 200 years…

    3) Regardless of what was going on earlier with the Black Death, evidence has been piling up for a 50M+-person dieoff (not the 5-10M of earlier guesses) in the Americas, with massive reforestration that covered previously-cleared land in Central America and the Amazon region. This was on top of any volcanoes and solar irradiance changes that occurred… but it’s hard to see anything comparable.

    Here’s a related article.

    Comment by John Mashey — 15 May 2010 @ 5:25 PM

  21. Dear BPL, You said:
    “It’s called “radiation physics,” Anne. You might want to research it. There are physical reasons for thinking CO2 is responsible. The theory is not based on correlations in climate data.”

    The best CO2 proxy estimates (for eg., see Frank et al, 2010)for the early part of the millenium have high values for atmospheric CO2. If it were all due to “radiation physics”, we would have had a medieval warm period and not just medieval climate regional anomalies, wouldn’t we?

    Which is the question raised/discussed by the post.

    Regards

    Comment by Anand — 15 May 2010 @ 8:59 PM

  22. Can anyone give me a reference or two to a paper, website or whatever that describes the details of the techniques employed in the actual drilling/coring, sample recovery/preservation and sub-sampling of ice cores like the one taken at Law Dome?

    [Response: Start here.-Jim]

    Comment by fhsiv — 15 May 2010 @ 9:35 PM

  23. I am reminded of a web page regularly posted by skeptics in the blogosphere, showing a world of medieval warming.

    The Medieval Warm Period – A global Phenomenon

    http://pages.science-skeptical.de/MWP/MedievalWarmPeriod.html

    Slightly more than cursory examination reveals that the warm peaks at various of the locations around the world on that map are offset by as much as 500 years. I guess the skeptics just look at the headline, unaware that they are providing corroboration for the lack of sync and sign between regions during the putative MWP much discussed in the literature.

    Comment by barry — 15 May 2010 @ 10:07 PM

  24. Anand, presenting “best CO2 proxy estimates” would likely be a full research paper — more than this Letter seems to even claim to present.
    You’re going beyond what the authors seem to be claiming.

    Letters are: http://www.nature.com/nature/authors/gta/#a1.2
    http://www.nature.com/authors/editorial_policies/peer_review.html

    It’s certainly interesting, going by the Abstract and supplement and figure that are available to the public (the actual Letter is of course paywalled). I’ll be curious to read James Annan’s comment on it. Is there one yet?

    Have you read the actual Letter, or are you posting someone else’s opinion? What’s your source for claiming this Letter contains the “best” estimates? Why do you consider your source reliable on this point?

    Your description of what’s in the Letter doesn’t seem to match the Figure they do make public there, though. Have you looked at it?

    Some links:

    http://www.ncdc.noaa.gov/paleo/pubs/frank2010/frank2010.html
    http://www.nature.com/nature/journal/v463/n7280/suppinfo/nature08769.html
    http://www.nature.com/nature/journal/v463/n7280/fig_tab/nature08769_F1.html#figure-title

    Comment by Hank Roberts — 15 May 2010 @ 10:37 PM

  25. It would appear that Peter Sinclair’s Climate Denial Crock of the Week has won. He took the lead about 3:00 AM East Coast Standard and by a little before midnight he was roughly 800 votes ahead. At end of count it was 5674 to 4859. Congratulations to everyone that was involved. As far as I am concerned we all won!

    However, now perhaps is a good time to start getting people to add http://climatecrocks.com to their blog lists. The posts may be videos, but the scripts are posted, certainly measure up and they are weekly.

    If they have any doubts, I would remind them what two leading climatologists had to say of his work:

    “…arresting graphics and straightforward explanations to point out what the science really says, how the contrarians distort and misinform.”

    -Gavin Schmidt, Goddard Institute for Space Studies, NASA; and,
    Micheal Mann, Director, Earth System Science Center, Penn State University

    Comment by Timothy Chase — 15 May 2010 @ 11:56 PM

  26. 16 Hank Roberts: I agree with you. I don’t see how CO2 could be local either. But the Black Plague hypothesis requires local CO2. So I was asking if I missed something. I think RC Jim answered it: “[Response: Very unlikely scenario–CO2 didn’t vary more than a few ppm over that time period, ……” Also look at the numbers 19 David B. Benson provided. He didn’t show every year, but it looks like nothing much happened with the CO2 over those years.
    Thanks for the link:
    http://www.nature.com/nature/journal/v463/n7280/fig_tab/nature08769_F1.html#figure-title
    which shows it even better. Holocene normal seems to be 280 ppm. Variation is quite small until the 20th century begins.

    This is turning out to be quite interesting.

    Comment by Edward Greisch — 16 May 2010 @ 2:09 AM

  27. A skeptic made the following argument to me with respect to the significant warming period 1985-2000:

    Skeptical Science – The albedo effect says that “A change of just 1% to the Earth’s albedo has a radiative effect of 3.4 W/m², comparable to the forcing from a doubling of CO2”. A reasonable statement.

    And RealClimate – Cloudy outlook for albedo? says “the ISCCP estimate shows a decreasing albedo trend of 1-2% in the 80s and 90s”. Not sure.

    Using ΔRF = 5.35 ln(CO2/CO2_orig), the no feedbacks forcing of CO2 added during the 15-year period was 0.34 W/m² based on 346 ppmv in 2000 and 369 ppmv in 1985. Even if all earlier forcing since industrialization (1.48 W/m²) is added we still only get 1.82 W/m² (I added this since most of the CO2 is still there, he didn’t).

    The skeptic’s conclusion is that CO2 is a minor player in climate change (0.34 W/m²). Rather, an albedo decrease (3.4 W/m² to 6.8 W/m²) was driving the warming for the period in question. This can’t be right since this is equivalent to a 2.5°C to 5.0°C temperature increase in 15 years (didn’t happen).

    Can someone explain the fallacy here?

    [Response: They are assuming instant equilibration. The planet does not respond instant;y to increases in forcing - mainly due to the heat capacity of the ocean which requires decades (and more) to rise. Secondly, the ISCCP trends are mostly due to satellite coverage and calibration issues and are far smaller than the ISCCP precision would justify. - gavin]

    Comment by SoundOff — 16 May 2010 @ 2:41 AM

  28. Now, to be serious for a change, John, I would only call the drop odd. That it took 200 years to recover is not odd, merely expected: after such a large drop, you would only get a quick recovery if there was an unusual and sudden increase.

    I would also like to point out that that date requires you take the graph as without error. But the line doesn’t have to *pass* a figure to return there: it has to be close enough to be indistinguishable given the error bars for that line.

    It would be better to use the peer reviewed work by someone skilled in this area and guild from it (or, if you wish to show the work incorrect, show its errors), rather than start with analysis on your own. Because not only has someone already taken time to consider what *ought* to be said of a graph, there’s a lot more information in a paper than you can fit here in a blog posting.

    Comment by Completely Fed Up — 16 May 2010 @ 4:16 AM

  29. Anand (#21),
    Do the (very basic) math: how much cooling would one you get out of a fall of 5 to 10 ppm in atmospheric CO2 from about 280 ppm with 3 C of sensitivity per doubling?

    Comment by Anonymous Coward — 16 May 2010 @ 5:43 AM

  30. Anand 21: The best CO2 proxy estimates (for eg., see Frank et al, 2010)for the early part of the millenium have high values for atmospheric CO2. If it were all due to “radiation physics”, we would have had a medieval warm period and not just medieval climate regional anomalies, wouldn’t we?
    Which is the question raised/discussed by the post.

    BPL: What was the Earth’s albedo back then? The cloud cover? The aerosol loading? Other greenhouse gases? Volcanic activity?

    It’s not all a one-to-one relationship between CO2 and temperature. That straw man exists only in the minds of denialists.

    [Response: Also note that the 'high' CO2 values are only a few ppm above the values in the LIA. The radiative forcing from 5ppm is 0.094 W/m2 - which would imply a temperature rise of 0.1 deg C at most (even assuming a very high end sensitivity). The GHG changes are taken into account when modelling the last millennium but they aren't dominant until you get to the 20th C. - gavin]

    Comment by Barton Paul Levenson — 16 May 2010 @ 6:09 AM

  31. John’s graph of the Law Dome CO2 levels is quite remarkable. Apparently,
    “In 1492, Columbus sailed the ocean blue”,
    spread new diseases to the Americas,
    which decimated the native Americans,
    allowing large scale reforestation,
    which sucked CO2 out of the atmosphere,
    which measurably reduced CO2 levels,
    possibly causing The Little Ice Age.
    It certainly makes sense: last I heard Native American population fell by up to 90% prior to the Jamestown Colony in 1609. Since many tribes did slash & burn agriculture, that’s a lot of reforestation.

    [Response: Let's not get carried away with conjecture here. As Mike noted, we should stay focused on the suite of (very interesting and) important scientific questions raised by this post--especially those related to the idea of spatial/temporal patterns of climate data in relation to concepts and models of their likely physical causes. Although the small but abrupt CO2 drop referred to represents a lot of potential forest carbon, it's insignificant as a global climate forcing. And there are large uncertainties wrt pre-historic land use changes and the non-atmospheric components of the carbon cycle.--Jim]

    Comment by Dennis — 16 May 2010 @ 7:06 AM

  32. Tom S (#2)
    AlCrawford (#7)
    I agree. A scientific article was long overdue. Hope to see more posts like this one at RC.

    Comment by Martin — 16 May 2010 @ 7:25 AM

  33. Ed (#26),
    The CO2 “hockey stick” arguably starts in the 1870s when the second industrial revolution was in full swing rather than in the 20th century. There was a pause afterwards but the rate of increase in atmospheric CO2 around 1880 would not be matched until the 1920s and not supassed until the 1950s (going by the Law Dome).

    Comment by Anonymous Coward — 16 May 2010 @ 8:01 AM

  34. Dr. Mann,

    I am pleased to see that you are still banging away with science education despite the numerous personal attacks you keep taking. You are a real pro.

    I am reminded of a quote one of my chemistry colleagues told me whan I kept losing my battles to raise the minimum math standards for non-majors science courses:

    The sign of a true pioneer is the number of arrows in his/her back.

    Scott A. Mandia, Professor of Physical Sciences
    Selden, NY
    Global Warming: Man or Myth?
    My Global Warming Blog
    Twitter: AGW_Prof
    “Global Warming Fact of the Day” Facebook Group

    [Response: Thanks for the kind words Scott. --mike]

    Comment by Scott A. Mandia — 16 May 2010 @ 8:45 AM

  35. Yes, it’s a beautiful speculation (that Columbus caused the Little Ice Age), but only speculation. A glance at the millennium temperatures seems to show a pre-existing cooling trend, and there’s a lot of variability between estimates and over time. Any temperature changes caused by a 3% drop in CO2 will be lost in the noise.
    Still, some temperature reconstructions show a dip at the expected time. (I’m looking at wikipedia’s graph http://en.wikipedia.org/wiki/File:1000_Year_Temperature_Comparison.png).
    Unfortunately, it’s no more speculative than a lot of putative cause&effect chains that are floating around in the noosphere. Maybe I’ll use it the next time I debate a climate cynic, since they love such spurious arguments.

    Comment by Dennis — 16 May 2010 @ 9:17 AM

  36. (#29) “Do the (very basic) math: how much cooling would one you get out of a fall of 5 to 10 ppm in atmospheric CO2 from about 280 ppm with 3 C of sensitivity per doubling?”
    Ans: 3% x 3C = 0.09C, which is consistent with the temperature changes in that time span (some of the reconstructions seem to show a change of up to 0.2C, but none show an increase). (using the graph in wikipedia)
    (Caveat: such a small change is lost in the noise. If the graphs would be black with error bars, if it showed them)

    [Response: A further point here is that the Law Dome data are more extreme wrt the CO2 drop in question, than are other high res. ice core data which show a smaller, and less abrupt decline at the end of the 16th century.--Jim]

    Comment by Dennis — 16 May 2010 @ 9:28 AM

  37. #36: Some reconstructions seem to have drops of as much as 0.6 to 0.9 C (eyeballing) depending on the period you’re considering. Others feature smaller changes. I don’t know which ones are most credible, hence my question in #4.
    In any case it seems that changes in heat distribution and insolation (see Mike’s post and Gavin’s comment) among other plausible factors had more impact than CO2. So the carbon cycle sensitivity to temperature should be more relevant than the climate sensitivity to CO2… or maybe not after all, considering that the ppm/C ratio around 280 ppm seems to be an order of magnitude higher when CO2 is a forcing rather than a feedback.

    Comment by Anonymous Coward — 16 May 2010 @ 11:00 AM

  38. I’d like to throw out one concerning anthrogenic climate forcings during the period in question (last millenia roughly). We know from the CO2 proxies that the global forcings were too small to be important. However if there were major changes in land use -perhaps driven by population diebacks, might not that produce some regional climate drivers (albedo of forest versus field, etc.)? Since these drivers are not globally diffuse, might they have some impact on atmospheric circulation, and hence regional climate shifts? I haven’t seen anyone in these comments talk about methane forcing, does the proxy dta show that the change in methane forcing was alaso too small?

    Comment by Thomas — 16 May 2010 @ 11:57 AM

  39. Okay, what I want to know is (I keep forgetting), what might a more la nina response mean for me in the Rio Grande Valley of Texas (about 50 miles west of the Gulf of Mexico).

    Does it mean more or less frequent/intense Atlantic hurricanes?

    Does it mean cooler or warmer weather?

    After the strongly negative arctic oscillation brought freezing weather from the arctic down to my doorstep here this winter and killed my tomato seedlings & lots of my tropical plants in Dec & Jan (most of which are growing back pretty well, and we planted more tomatoes), I’d like to know.

    I’d been thinking all along how utterly horrible AGW is, esp all the death and destruction it is and will be causing, but at least we wouldn’t get freezes here anymore, or they’d be much less frequent.

    Comment by Lynn Vincentnathan — 16 May 2010 @ 12:08 PM

  40. Lynn, my understanding is that there is no solid answer to your tomato question.

    “Climate is what one expects; weather is what one gets,” to nearly get the Mark Twain quote correct (I haven’t bothered to look it up for word for word accuracy).

    So a shift of climate doesn’t mean it won’t ever frost in Florida. It just means it will become more unusual than it is now.

    The pain comes in the establishment of the “new normal” in the climate. Crops and timing of planting and harvest will change, as will a host of secondary effects. I had a friend from Canada ask about the HVAC unit we had installed (one of those high efficiency deals), and was curious that I was rather disinterested on how well it heated the house. Here in Alabama we’re far more interested in cooling and pulling humidity out of the inside air, which isn’t such a big concern for folks in the Great White North.

    We may well see where the importance of units that cool as well as heat moves with the adjustment of climate – and the need for heat to move south.

    On plagues and climate, let’s remember that the unclimate like cold of Europe was driving folks inside, furthering the spread of the Black Plague, and that the return to warmer climates (particularly on the north Med), lead to the flowering of technology (along with a lot of great plants Columbus brought back), aided by a reduction of population pressure.

    Likewise, the plague didn’t strike uniformly. Some cities in Europe were decimated while others in relatively close proximity weren’t touched at all. And it wasn’t just one sweep; there were several waves of the Black Death that happened with large gaps between them.

    I’m very encouraged that RC has returned to science!

    Comment by Frank Giger — 16 May 2010 @ 12:39 PM

  41. re: 28
    This started with the Black Death, and I mostly pointed out the Law Dome data because I already had that chart around to show that if there were a plague-induced die-off that actually made a noticeable difference, it was likely to be the later one in the Americas. I am quite familiar with “Correlation is not causation”, and fact that ice-core records differ, and dates aren’t accurate to a year. I urge people to keep on eye on The Holocene for an issue that I think will have a bunch of interesting papers.

    Does anyone think that (currently) reforestration/forest preservation can have the slightest useful effect on CO2? If your answer is NO, then for sure, then the 1500s speculation is irrelevant. If your answer is YES, then it just might be possible that a much larger reforestration (land reclaimed by high-density, fast-growing Neotropical biomass from that used by 50M people doing low-density agriculture) might have had an effect…
    One more time: the relevant-to-this-post interesting scientific question is whether or not a cooling that certainly happened would have had different *regional* fingerprints depending on the relative contributions of:

    a) Changes in volcanoes + solar irradiance
    b) Changes in CO2 from massive reforestration
    c) Feedback from lower

    I suggest, to avoid hijacking this thread (and I don’t have time to drag out the various references I’ve studied, and which I suspect not everyone has), that for this thread, the relevant issue to debate is NOT whether the die-off caused this, but whether different combinations of the above would have showed different fingerprints. After all, people do lots of “what-if” models for various scenarios, and this doesn’t seem any different.

    Comment by John Mashey — 16 May 2010 @ 12:44 PM

  42. for lynn V
    http://www.esrl.noaa.gov/psd/enso/compare/
    keep in mind there are many other factors going on
    like http://www.ncdc.noaa.gov/teleconnections/
    or the State Of the Climate report http://www.ncdc.noaa.gov/bams-state-of-the-climate/
    hope this helps
    PS
    to RC keep up the good work

    Comment by jl — 16 May 2010 @ 1:00 PM

  43. Is it true that what we currently label the MWP, used to be called
    the “Medieval Optimum?” Maybe the intention of bringing clarity and understanding by renaming events, might conversely create greater confusion.
    Just sayin’

    Comment by Smitty — 16 May 2010 @ 1:14 PM

  44. I second Scott Mandia’s comments on your courage, Mike – many people would turn and run away, rather than continue to fight misconceptions, when they were subject to the kind of attack you have been.

    Keep up the good work, and thanks for this great overview, it was a very clear and interesting post.

    [Response: thanks :) --mike]

    Comment by Kate — 16 May 2010 @ 2:36 PM

  45. “Does anyone think that (currently) reforestration/forest preservation can have the slightest useful effect on CO2?”

    You would have to search for the inevitable consequence of reforestation at the level to produce that effect.

    Rather like the precession of the orbit of mercury was a consequence of general relativity.

    If that much CO2 was taken out by tree building, what other effects would occur?

    Albedo changes? O2 changes, Rainfall runoff and alluvial basin thinning?

    How much land would have changed, and where could that have been?

    Think of the things that would be the consequence of your theory to explain CO2 changes but are not themselves the CO2 nor things that could change CO2, else you have a self-referential theory that cannot distinguish between itself and other theories that reduce CO2.

    Only some of the alternate theories have the same consequence, and you can thin the herd.

    If that consequence doesn’t appear, then you’ve removed that from being the major cause.

    Comment by Completely Fed Up — 16 May 2010 @ 2:40 PM

  46. Hank Roberts:
    Thanks for your comments

    Yes, I have read the paper. I discussed this paper in Jim Bouldin’s thread over a three-week period some time back at RC. There is a thread “Good news for the earth’s climate” (or SLT).

    The paper incorporates the ‘best’ possible estimates for early millenial CO2 – those are not great considering how far back we are trying to project, but one could argue the same about temperatures as well. We have to do with what we have.

    Gavin:
    I read R. Lindzen’s explanation that the CO2 GHG effect yield is highest when its concentrations are lower i.e., doublings at lower CO2 conc. produce greater GHG effect than at higher concentrations.

    If this were true, the CO2 fluctuations during the MWP/LIA should have had a greater effect than seen with the higher concentrations seen today. Is this correct? Especially with the emergence from the LIA.

    Another thing is – if we set up the argument that the present CO2-predominant regime is very different from any situation hitherto seen, how and what can we ‘learn’ from the climate of the recent past?

    Michael/Jim
    Is it the right approach to look at or calculate the temperature anomaly as an indicator of global change, or, is it simply sufficient to have high resolution regional histories right? And what drives what?
    The apparent circularity of arguments (at-least to me) is beyond my ability to break out of.

    Dr Mann, You should fight the good fight. :)

    BPL:
    You cannot call “CO2 is the main climate driver” argument a denier strawman, and use a variant of it yourself!

    Regards

    Comment by Anand — 16 May 2010 @ 3:22 PM

  47. We don’t need to do millenial timescale reconstruction for certain ecosystem responses. In 1994, The Oregon State Board of Forestry published a collection of over 200 papers called “Cumulative Effects of Logging in Oregon”. Siltation and ecosystem simplification were noted to be serious and long term legacies, but measurements of microclimate temperature alterations were fascinating.

    Both air and adjacent stream temperatures were noted to be several degrees or more higher after industrial logging, to the point that habitable temperature bands for andromonous fish were compromised, and aquatic food webs altered.

    These changes persisted and in some cases were long term, because even if the trees were reestablished, stream ecosystems had headed into different trajectories.

    Similarly, after the forests of Greece and Turkey were destroyed several millenia ago, hotter and drier microclimates prevented their reestablishment.

    This is slightly OT to this post, but there is detailed data under our noses about changing microclimate effects on ecosystems that is relatively recent. If you can find the book in the interlibrary lending system, that is- the timber industry suppressed this detailed report soon after it appeared. Tim Hermach of Native Forest Council has hard copies for those who are interested.

    Comment by mike roddy — 16 May 2010 @ 3:34 PM

  48. “Medieval Climate Anomaly” is nicely value-free, but implies that the Medieval climate was somehow anomalous compared to other periods. Is there any evidence that the MCA departed farther from some suitable multi-millenial mean than other carefully-chosen 500-year intervals?

    The immediate pre-industrial period may be the basis for our sense of normal, making medieval climate seems anomalous, but it seems to me that over a multi-millenial horizon the “Little Ice Age” is much more of a climate anomaly than what some prefer to call the Medieval Climate Anomaly.

    In the broadest sense, the natural forcings appear to exhibit sufficient variability to cause climate to be nothing more than a sequence of anomalies. Just as the weather is never normal, neither is the climate.

    Comment by John N-G — 16 May 2010 @ 4:08 PM

  49. (1) Law Dome CO2 records are of the highest quality. (1.1) Law Dome was chosen to obtain an ice core for exactly this reason. (1.2) Law Dome records overlap the Keeling cuvre until 1978 CE. The two records agree to within 0.25% (0.0025) up until 1972 CE and then the data for 1972, 1972, 1977 & 1978 agrees to within 0.5%. (I suspect these small variations are due to being at the end together with “20 year smoothing”. (1.3) If other Antarctic ice cores disagree with Law DOme I’ll take that as evidence of the inferior quality of such other cores; the usual difficulty is dating, a problem which Law DOme does not suffer from.

    (2) While
    http://en.wikipedia.org/wiki/Charles_C._Mann
    is not an anthropolgist, his scientific journalism is of high stand and his
    http://en.wikipedia.org/wiki/1491:_New_Revelations_of_the_Americas_Before_Columbus
    is generally on the right track, as shown more recent reasearch in, for example, the Amazon Basin (see a recent issure of Scientific American).
    One concludes a tremendous decline in agriculture throughout the Americas in the century following Columbus.

    (3) The conclusion that CO2 concentrations declined to a minimum around 1610 CE then follows, in agreement with Law Dome data.

    (4) But, by itself, that decline in CO2 concentrations appears insufficent to explain LIA and other factors, inlcuding the Maunder Minimum, are known.

    (5) More puzzling are the temperature profiles during LIA from locations in the southern hemisphere.

    Comment by David B. Benson — 16 May 2010 @ 5:22 PM

  50. John N-G (48) — Exactly so.

    While central Greenland palotemperatures (GISP2) only indicate the general trends in that region (northern North Atlantic), looking at Richard Alley’s GISP2 data over the Holocene suggests nothing at all remarkable about MCA; temperatures wobble on all time scales.

    Comment by David B. Benson — 16 May 2010 @ 5:27 PM

  51. “Detection of Human Influence on a New, Validated 1500-Year Temperature Reconstruction” Gabriele C. Hegerl, Thomas J. Crowley, Myles Allen, William T. Hyde, Henry N. Pollack, Jason Smerdon, and Eduardo Zorita
    http://journals.ametsoc.org/doi/full/10.1175/JCLI4011.1
    From the abstract: A new reconstruction using this method shows substantial variability over the last 1500 yr. This record is consistent with independent temperature change estimates from borehole geothermal records, compared over the same spatial and temporal domain. The record is also broadly consistent with other recent reconstructions that attempt to fully recover low-frequency climate variability in their central estimate.

    Comment by David B. Benson — 16 May 2010 @ 5:44 PM

  52. Anand (46) — Arrhenius’s approximation
    http://en.wikipedia.org/wiki/Svante_Arrhenius#Greenhouse_effect
    holds over all CO2 concentrations of interest. For more detail see the IPCC AR4 WG1 report.

    Comment by David B. Benson — 16 May 2010 @ 6:31 PM

  53. #20

    The “sharp” drop in CO2 on the graph looks large only because of the way the data is graphed; any fluctuation can be made to appear large if the vertical range of the graph is sufficiently small. See how significant that drop looks if the data is re-plotted with a lower limit of zero rather than 270 ppm.

    Comment by Jerry Steffens — 16 May 2010 @ 6:46 PM

  54. Anand 46: You cannot call “CO2 is the main climate driver” argument a denier strawman, and use a variant of it yourself!

    BPL: Read a book, okay? I mean one on climatology.

    Comment by Barton Paul Levenson — 16 May 2010 @ 7:05 PM

  55. Prof. Mann,

    I´d like to learn more about how data infilling is done. Is there any online starting point you would suggest?

    [Response: You can find some discussion about this and some relevant references for further details, in the supplementary online information. The key reference is Schneider, Journal of Climate, 14, 853–871 (2001), available here. --mike]

    Comment by Alexandre — 16 May 2010 @ 8:30 PM

  56. 20 John Mashey: Thanks much for the graph of CO2 from the ice core. The points you marked in red aren’t that big of a dip IMHO. But they do look like a small dip. Perhaps a plague could do that by allowing a lot of trees to grow.
    RC: Does this rise to the level of needing research, or shall we just leave it?

    [Response: It's not relevant to the topics Mike raises in the post, because as has been pointed out repeatedly now, the amount of CO2 involved relative to radiative forcing requirements for creating the LIA are completely insufficient, not to mention the other issues I mentioned. Why people are obsessed with this I have no idea.--Jim]

    Comment by Edward Greisch — 17 May 2010 @ 1:26 AM

  57. 34 Scott A. Mandia: Just keep on trying to raise the math and science standards for those innumerate humanitology majors. We have been kicked around by them for too long. It is high time for ALL college students to be required to take the Engineering and Science Core curriculum at the very least. They need exposure to reality.

    Comment by Edward Greisch — 17 May 2010 @ 1:40 AM

  58. Jim Bouldin says: “Very unlikely scenario–CO2 didn’t vary more than a few ppm over that time period, and the amount of land cover change possible at the time (minimal) is in concert with that. Further, albedo generally goes down with increasing tree cover, not up, albeit countered by evapotranspirational increases.”

    Solar variations and supposed volcanism are also highly uncertain – are they enough to account for the observed temperature changes in those time periods? What’s the relative difference there?

    Note that published records of CO2 changes in this time frame dispute the claim of a “few ppm” changes:

    Atmospheric CO2 reconstructions are currently available from direct measurements of air enclosures in Antarctic ice and,
    alternatively, from stomatal frequency analysis performed on fossil leaves. A period where both methods consistently
    provide evidence for natural CO2 changes is during the 13th century AD. The results of the two independent methods
    differ significantly in the amplitude of the estimated CO2 changes (10 ppmv ice versus 34 ppmv stomatal frequency).

    http://www.phys.uu.nl/~wal/research/papers/hoofetal2005.pdf

    Hence, dismissing this notion out of hand seems unsupportable – you can’t keep ignoring the carbon cycle – and given that the work seems carefully done, peer-reviewed and published, why do so? The authors aren’t claiming that this is the only cause, after all:

    Nevle and Bird don’t attribute all of the cooling during the Little Ice Age to reforestation in the Americas.
    “There are other causes at play,” Nevle said. “But reforestation is certainly a first-order contributor.”

    All in all, there seems to be decent evidence that indicates human activity was modifying the global climate – slowly – during the past thousand years – not via fossil fuels, but rather by land use changes. In addition, you should consider the amount of black carbon released via humans burning off grasslands and cutting down trees – it would have a certain warming potential, correct? So, if population crashes in Europe and the Americas reduced atmospheric black carbon and increased CO2 uptake (and that seems to have happened, based on carbon isotope ratio studies), then the combined effect could be significant over several centuries – and thus could play a role in explaining both the Medieval Warm Period and the Little Ice Age. This also raises the question of when the “Industrial Warm Period” really began – could that have been what terminated the Little Ice Age?

    On the black carbon issue:
    Brown Haze from Cooking Fires Cooking Earth, Too, 2007

    Given that future carbon cycle uncertainties will play major roles in the future climate trajectory, the carbon cycle deserves a bit more focus – such as:

    1) 1. Uncertain ocean responses with respect to future carbon uptake

    2) 2. Uncertain permafrost / soil carbon responses under warming scenarios

    As far as the LIA and the MWP, I know that realclimate authors & co-workers prefer the solar/volcanic hypothesis along with some kind of interaction from “shifting ocean modes” – but the evidence for such multi-decade/century-scale ocean modes is still based on statistical arguments, not on any well-defined mechanism, correct? I think much of it involves misapplication of time series data analysis to proxy records, in fact – and when you look for mechanistic explanations, you won’t find any. Many of those “modes” were discovered by researchers running time series analysis against some dubious proxy records (Pacific salmon catch records, for example?) – it just doesn’t seem very reliable – but this is the general argument being promoted:

    For example, Shindell et al (Science, 2001) showed model results that suggested solar forcing could lead to enhanced winter cooling over certain regions of the Northern Hemisphere such as Europe during the Late Maunder Minimum (the coolest part of the European “Little Ice Age”, the late 17th and early 18th centuries). The mechanism involves the large-scale dynamical response of the atmosphere to the estimated decrease in solar irradiance and subsequent stratospheric ozone change. The response was associated with a shift towards the negative phase of the so-called North Atlantic Oscillation (NAO)/Arctic Oscillation (AO) which projects onto a pattern of regional warmth and coldness that tends to cancel out in an average over the entire Northern Hemisphere. There is supporting evidence for this idea based on widespread proxy evidence for a negative phase of the NAO during late 17th and early 18th century intervals.

    Nice idea, but I don’t think it justifies entirely ignoring the carbon cycle issues.

    I’d go into more detail on EOFs and time series analysis – but that topic’s been rejected before, hasn’t it?

    In fact, the evidence for decadal oscillations in the ocean is pretty weak. [edit--that's enough of your indiscriminate bashing of legitimate climate research efforts. we've allowed you to make these dubious arguments several times now. you can take it your own site if you like, but we've had enough of it here.]

    [Response: Nobody's ignoring the carbon cycle--the opposite in fact. The idea--at least as applied to the late 16th century, is not as far fetched as I first thought, and the Nevle and Bird paper is definitely one I'll be reading closely. It's highly likely that the drop in Indian populations increased carbon sequestration, but if you assume that the Law Dome data are "truth", then a drop of 7-8 ppm (=16 Gt C) over 35 years requires an enormous amount of land, greater even than their estimated 50 million impacted hectares--and also is not supported by the subsequent rapid increase in CO2 after that time--just at about the time you would expect a rapidly accelerating sequestration.--Jim]

    Comment by Ike Solem — 17 May 2010 @ 7:02 AM

  59. Re #31…

    Columbus sailed the ocean blue in 1492, but the Amerindian population losses were spread out over several centuries, starting mainly in the 1520s in Mexico. Europe’s 14th century demographic decline really begins 40+ years before the Black Death with the famine in 1315-1316(c. 10% population decline?)due to poor harvests caused by unusually cold wet weather.

    Jest sayin’…

    Comment by Sufferin' Succotash — 17 May 2010 @ 7:30 AM

  60. Mike, welcome back. I hope you get some more positive comments here. I posted a petition to support you and Phil Jones and had some good comments there too: http://www.petitiononline.com/clim4tr/petition.html

    It’s good to get back to a touch of realism about what we are doing studying the medieval climate. If arguing over who did what in a 1998 paper is the best the denial people can do, I wonder how they think science really works.

    [Response: Well put. Thanks so much Philip! --mike]

    Comment by Philip Machanick — 17 May 2010 @ 7:59 AM

  61. Even if depopulation after the Black Death played a role, one’d then also have to take into account the changes in agriculture brought about by the BD.

    The reduced population meant that labour intensive farming had to be cut back from lack of serfs. In place of it the number cattle of grew greatly since they can be kept by a single cowherd for extended periods of time. So one could even speculate that increased populations of cattle would have to give higher methane emissions with subsequent warming. I’m not aware of any evidence for such a hypothesis, though.

    Hasn’t there been claims that the MCA could in part be due to deforrestation of South America by the booming cultures there?

    Comment by Sili — 17 May 2010 @ 8:43 AM

  62. I’ll add my small vote of appreciation for the science post – and especially for one by a most excellent scientist. Heartening to see Dr Mann carrying on providing his insights. Thank you!!

    Comment by flxible — 17 May 2010 @ 9:27 AM

  63. Ike (#58),
    One last time: the dates do not match. 14th century events can not explain the carbon cycle of the 13th century. If you want demographic catastrophes in the 13th century, look to Asia!

    Comment by Anonymous Coward — 17 May 2010 @ 9:27 AM

  64. Jerry, plotting from zero is as bad in demonstrating statistics as is plotting too narrowly, as it does the reverse – disguising changes in the trend.

    When I did trend analysis a lot of thought went into scaling; sometimes it was from zero, and other times it wasn’t. Typically we used double the top and bottom peaks, other times roughly one standard deviation from the mean, and others two standard deviations with markings for the bands.

    The charts in question are clearly marked to scale; it is assumed by the author that one is used to working with statistics and can interpolate how it fits on a zero scale. Or atleast I’m assuminging that what they’re assuming. ;)

    I also assumed good faith as there wasn’t any tomfoolery such as having the upward lines extend past the listed scaling, always a big tip-off.

    Let’s keep skepticism in the good faith of activists completely segregated from scientists working in good faith, as they should be considered mutually exclusive, IMHO.

    And remember that charts aren’t analysis any more than the pictures in a book are the story. They’re simply aids in helping illustrate main points of the text.

    Comment by Frank Giger — 17 May 2010 @ 10:47 AM

  65. Just a little anectode (hopefully not too off-topic) that pretty much sums up the Mann-bashing denial movement…

    Had a brief discussion about global-warming with a very so-so engineer at work not long ago. A few minutes into the discussion, he treated me to a “Mann’s method generates hockey-sticks from random noise” song-and-dance routine.

    So I asked him, “How would a random-noise eivenvalue spectrum compare with Mann’s hockey-stick eigenvalue spectrum?”

    His reply was along the lines of, “Uhhhh…. what’s an eigenvalue?”

    Needless to say, that’s where the conversation ended.

    Comment by caerbannog — 17 May 2010 @ 11:11 AM

  66. arrgh… anecdote!

    Comment by caerbannog — 17 May 2010 @ 11:12 AM

  67. Mike,
    Illegitimi Non Carborundum – Don’t let the bastards grind you down! Thanks for staying in the good fight. When the time comes for remembering who was right and who was wrong, your name will be on the side of good.

    OT: Just read this article in SciAm (yeah yeah, I know): http://www.scientificamerican.com/article.cfm?id=arctic-plants-feel-the-heat

    Which has me wondering, how many non-temperature indicators are there of AGW? Is there a list? Just off the top of my head:

    GRACE showing decline in ice sheets
    Tundra greening, and Taiga browning
    Plants, animals, and insects shifting either towards the poles or higher altitudes
    Sea level rising
    Migrating animals returning sooner and leaving later, or not leaving at all
    More growing days

    Comment by Richard Hendricks — 17 May 2010 @ 11:46 AM

  68. Richard Hendricks @ 67:

    I went for several =years= without wearing a jacket.
    A/C stopped running in November, started running again in February.
    No peach harvest for =years= due to a lack of chilling hours.
    Had to mow the lawn (assuming it wasn’t a hard summer drought year, which is actually fairly normal where I live) well into the Fall, and started much earlier in the Spring many years.

    Someone needs to make a web page that collects these. They are much more “human” than forcings and error bars and satellite data.

    Comment by FurryCatHerder — 17 May 2010 @ 12:10 PM

  69. “68FurryCatHerder says:
    17 May 2010 at 12:10 PM
    Richard Hendricks @ 67:

    …Someone needs to make a web page that collects these. They are much more “human” than forcings and error bars and satellite data.”

    True, but then the denial crowd just changes course again and admits that while things might be warming, we can’t prove it’s because of human-produced CO2. :-P

    Of course, they never offer an alternative explanation, either…unless it’s just to hand-wave it away with “it’s natural”.

    Comment by Witgren — 17 May 2010 @ 12:36 PM

  70. “he treated me to a “Mann’s method generates hockey-sticks from random noise” song-and-dance routine.”

    It always seemed to me that this “random noise” thing required “random noise” to mean “something that more normally increases than decreases the value”, which has always had me wondering: isn’t this what an “upward trend” means?

    You know, just like the stock market. Or population. However, nobody says “the stock market is just random”, do they?

    Comment by Completely Fed Up — 17 May 2010 @ 1:07 PM

  71. > nobody says
    Nobody says the stock market is _just_ random. Emphasis required.
    doi:10.2307/2330525 Cited by 208
    Beta as a random coefficient
    “… This would explain why the average NYSE stock has less than half of its total risk explained by market forces ….”

    Comment by Hank Roberts — 17 May 2010 @ 2:21 PM

  72. Indeed eric. Confidence intervals, level of confidence and the like in terms of probability/inferential statistics also plays important roles when high likelihoods are attached. It is erroneous for people to expect an exact point estimation of such complex system dynamics. I also want to second the earlier encouraging words to Dr. Mann: keep up the hard work in the scientific analysis.

    RC is a great resource even with some of those wikipedia references:)

    Comment by Jacob Mack — 17 May 2010 @ 3:03 PM

  73. One has to be very careful along that track, CatHerder.

    We had a three year drought in Georgia. Every politician and activist talked it up as proof of global warming. Lake Lanier is as down as it ever has been! Act now to save the planet! (Pay no attention to the unreasonable demands placed on the water supply due to incredible increases in population as well as the drought).

    At the same time, other frustrated politicians tired of being told they had to fix the problem simply said the answer was to pray for rain.

    Then it broke, as it was more cyclical than anything else. Lake Lanier filled.

    And with it, all the credibility for the folks who had banked the bulk of their arguments on the drought as proof of global warming.

    Preachers, however, made much hay over the rains coming after the call for prayer.

    Both were dead wrong.

    Comment by Frank Giger — 17 May 2010 @ 3:25 PM

  74. FCh: admittedly, there are limits to what any math alone can do. The measurements of central tendency,using error bars, and other legitimate methods within statistics, are still very effective in summarizing and explaining raw data findings. For example in genetics and elsewhere, the chi-square method is indispensable. Using weighted means and following the tenets of Chebshev’s theorem do matter. Real data is being used, with real empirical observations, with satellite data, with paleo-climate reconstructions, in consideration of the actual laws of physics, and there is no way this can all be analyzed without those “forcings” and “error bars.”

    Granted climate is non-linear and is also analysed using calculus with some facotors being considered noise out of necessity in such a complex system, however, the same can be said in Theoretical Physics, Physical Chemistry (with assigned probabilities in terms of the wave function)and many aspects of Developmental Biology. Epdemiological studies are analyzed and summarized using mathematics. When using X^2 or p hat analysis, for example, there are inferences made based upon the confidence interval (the former) and percentage found based upon the decimal quotient (the latter).

    With so much data the null hypothesis must be rejected; H0:mu = k. The global mean temperature has increased since the industrial age even when considering boundary conditions on the graph.

    This is a gross oversimplification in several ways,but I find it interesting that most people who seriously deny the statistics in climate science do not grasp or deny even Elementary Statistics.

    References

    Bluman A., (2009) Elementary Statistics A Step By Step Approach.

    International Edition chapters 3,6,7, & 8.

    Storch H., & Zwiers F., (1999) Stastical Analysis in Climate Research.

    Chapters 1& 2.

    And yes Atkins as always:)

    Comment by Jacob Mack — 17 May 2010 @ 3:28 PM

  75. FCH – here is another warming anecdote to add to the collection.

    My wife and I live in Austin, TX, and about three weeks ago at dusk we were treated to the sight of pairs and trios of large ducks flying to, and roosting in the oak trees adjacent to the restaurant we were at. Never having seen ducks perching in trees (about a km from the nearest body of water) we did some investigating and found that they are Black-bellied Whistling Ducks. Impressive birds. As recently as 2005 they were listed as a rare sighting by the local Audobon Society, but here there were about two dozen up in the oaks, calling to one another and staring down at the people below.

    What I found interesting in my brief investigation was that in a 70′s vintage North American bird guide they were not listed at all. Move forward to the 80′s and they were listed as a Central American bird occasionally blown north to south Texas. In the 90′s they were described as breeding in south Texas and occasionally seen further north. In the latest field guides and on the intertubes they are shown as breeding through much of the gulf states and have been sighted as far north as Pennsylvania.

    Any predictions on when Black-bellied Whistling Ducks will make it to Canada?

    Comment by Phillip Shaw — 17 May 2010 @ 3:48 PM

  76. The stock market has plenty of random variation.

    Comment by Jacob Mack — 17 May 2010 @ 4:23 PM

  77. Frank Giger wrote: “And with it, all the credibility for the folks who had banked the bulk of their arguments on the drought as proof of global warming.”

    How do you know the drought in Georgia was NOT caused by global warming? Because it didn’t last forever? There is no reason to expect that every drought caused by global warming will be permanent. There IS reason to believe that global warming will cause more frequent, more intense and more prolonged droughts in many regions.

    Frank Giger wrote: “Then it broke, as it was more cyclical than anything else.”

    What “cycle” are you referring to? Is there a known “cycle” of drought in Georgia?

    Comment by SecularAnimist — 17 May 2010 @ 4:39 PM

  78. By the way, here’s the kind of claims that are being made about the “Pacific Decadal Oscillation” (the one ‘discovered’ in the salmon catch proxy data) by Don Easterbrook:

    A prominent U.S. geologist is urging the world to forget about global warming because global cooling has already begun.

    Projected cooling for the next several decades is based on past PDO patterns for the past century and temperature patterns for the past 500 years. Three possible scenarios are shown: (1) global cooling similar to the global cooling of 1945 to 1977, (2) global cooling similar to the cool period from 1880 to 1915, and (3) global cooling similar to the Dalton Minimum from 1790 to 1820…

    The more itemized claims from Don Easterbrook are as follows:

    1. The PDO has a regular cyclic pattern with alternating warm and cool modes every 25-30 years
    2. The PDO has accurately matched each global climate change over the past century and may be used as a predictive tool.
    3. Since the switch of the PDO from warm to cool in 1999, global temperatures have not exceeded the 1998 high.
    4. Each time the PDO has changed from one mode to another, it has stayed in that mode for 25-30 years; thus, since the switch of the PDO from warm to cool in 1999 has been entrenched, it will undoubtedly stay in its cool mode for another several decades.
    5. With the PDO in cool mode for another several decades, we can expect another several decades of cooling.

    That’s from the linked study at http://dotearth.blogs.nytimes.com/2010/05/17/world-warm-chicago-cooling/. (Revkin contrasts that claim to the warming East African lakes)

    Any critiques of Easterbrook’s claims from realclimate, or does that sound reasonable?

    Comment by Ike Solem — 17 May 2010 @ 4:44 PM

  79. Thanks, jl (#42), I’ll write it on my hand this time :)

    La nina, more Atlantic hurricanes, warmer anomalies for my area (that little point of Texas deep in the heart of Mexico).

    And I guess we don’t really know what to expect of the arctic oscillation — whether to expect more positives or negatives or about the same.

    So now I can definitively say I don’t like the implications of this post at all. More (or more intense) hurricanes, hotter climate over here. Pooh. And who knows, maybe more frequent (or the same) negative AOs to freeze out my plants in snap winter freezes. Just what I don’t want.

    But unlike the denialists who would bury their heads in the sand and kick sand up in the faces of the scientists & kill the messengers. I’m just going to have to redouble my efforts at mitigating and getting others to mitigate climate change. That’s all there is to it.

    Thanks Mike for the useful info.

    Comment by Lynn Vincentnathan — 17 May 2010 @ 4:54 PM

  80. Richard Hendricks #67

    Which has me wondering, how many non-temperature indicators are there of AGW? Is there a list? Just off the top of my head:

    GRACE showing decline in ice sheets
    Tundra greening, and Taiga browning
    Plants, animals, and insects shifting either towards the poles or higher altitudes
    Sea level rising
    Migrating animals returning sooner and leaving later, or not leaving at all
    More growing days

    A few more:
    ocean acidification
    increasing toxicity of cassava
    direct observation of glacier retreat

    Long list for UK here: http://www.ecn.ac.uk/Education/indicators_of_climate_change.htm

    A few predictions are turning out harder to relate to climate change than expected (e.g. someone yesterday told me the historical epidemiology of tropical diseases suggests that spread of insects does not result in as rapid a spread of the diseases they carry as you’d expect — my guess is because e.g. mosquitoes carrying malaria have short lifetimes and new populations need infected hosts to spread the infection).

    Comment by Philip Machanick — 17 May 2010 @ 5:20 PM

  81. Ike Solem @ 78:

    This is the type of information that I =wish= “the good guys” would talk up a lot more. I don’t know if its the PDO (could be) or my personal fave, GCRs (could be), but I do know that we seem to be moving sideways for about 10 years now, and both the PDO and GCRs are expected to change their direction of influence in the next decade or three.

    And when that happens, and it will, life on Planet Earth is going to be far more unpleasant than if people would just learn to understand that when the temperature goes up and down, and it goes up more than down, that going sideways or even a little down doesn’t mean it isn’t going to go up a LOT.

    People need to understand that action =now= is absolutely essential. It’s like the calm before the storm. The storm =is= coming, and we need to act =now= before we can’t.

    Comment by FurryCatHerder — 17 May 2010 @ 5:46 PM

  82. Dear Dr. Mann,

    I am sorry about these attacks. Do not underestimate these people.

    There is a Russian TV station called Russia Today (RT) that has given a lot of time to denialists like the 9-11 Truther Alex Jones and that other goofball Lord Monckton. You can search “Russia Today” “climate change” to see for yourself. RT is close to the Kremlin, I believe. See the RT clips on Youtube.

    I read that the famous Russian scientist Roald Sagdeev signed that open letter. Do you understand how huge this is for you? You should write about this on your site. Maybe you are young and don’t know about what Dr. Sagdeev did. You climate scientists should all thank him. He stood up to the KGB propaganda on behalf of the Soviet Academy of Sciences and now he stands up for you.

    In 1987, Dr. Sagdeev denounced the KGB propaganda about AIDS being made by crafty US scientists. Right in Isvestia. In 1992, the KGB chief Primakov said right in Ivvestia:

    Izvestiya (3-19-92) reported on March 19, 1992:

    “[Primakov] mentioned the well known articles printed a few years ago in our central newspapers about AIDS supposedly originating from secret Pentagon laboratories. According to Yevgeni Primakov, the articles exposing US scientists’ ‘crafty’ plots were fabricated in KGB offices.”

    KGB Chief Primakov actually said:

    “Articles exposing US scientists’ ‘crafty’ plots were fabricated in KGB offices.”

    I know a lot about that campaign, and the attacks on the alleged “plots” of “crafty climate scientists” strike me as very similar to the KGB AIDS propaganda which characterized AIDS as a plot by US scientists. This is all a variant on the old anti-Semitic canards about Jews spreading diseases, plotting world domination, etc.

    Here is my main article article about Sagdeev’s role in denouncing the AIDS propaganda. I think you all might learn from this.

    http://legendofpineridge.blogspot.com/2010/05/prominent-scientists-publish-open.html

    The denialist Marc Morano even linked to my obscure blog (article below) to mock me, but he doesn’t tell that Dr. Sagdeev signed that letter. This is different than my article about Sagdeev (above).

    http://legendofpineridge.blogspot.com/2010/05/leading-scientists-publish-open-letter.html

    These denialists are not going to stop. They just had a conference in Chicago. You might want to take note of the Russian media on global warming. It sounds exactly like the denialists and FOX News.

    Inhofe cites the Russian Andrei Kapitsa, who has been closely associated with Russian TV for decades and a Russian economist named Andrei Illarionov who has a think tank called The Institute for Economic Analysis in Russia as well as a position with the Libertarian Cato Institute. Illarionov used to be a big cheese in Gazprom.

    President Medvedev is the former Chairman of the Board of Gazprom. Many former KGB went into Gazprom. Those Gazprom guys want to be able to do whatever they want. Maybe that’s why they like Libertarians.

    The AIDS campaign probably began in the US according to the CIA.
    http://legendofpineridge.blogspot.com/2010/05/prominent-scientists-publish-open.html

    The KGB promote junk science in Russia, but most Russian scientists don’t agree with it. They are just afraid.

    For example the KGB used a fake mental illness called Sluggish Schizophrenia to hospitalize dissidents. Most Soviet psychiatrists didn’t want to cooperate.

    Comment by Snapple — 17 May 2010 @ 5:50 PM

  83. # 80: quote: “(e.g. someone yesterday told me the historical epidemiology of tropical diseases suggests that spread of insects does not result in as rapid a spread of the diseases they carry as you’d expect — my guess is because e.g. mosquitoes carrying malaria have short lifetimes and new populations need infected hosts to spread the infection).”

    Hmmm, fromt the epdemiological research I am looking at and from several discussions with Microbiology and entomology professors, the spread is still quite rapid and widespread. Then again “as you’d expect,” is a vague and not specific modifier. How fast would one expect it to spread?

    For one some people resist such diseases like malaria better than others, there are insect nets, insecticides, sporulating phases, and insects who simply are die prior to behaving as vectors of disease (as you stated) Think of it this way: not every at risk sexual behavior with a HIV positive person results in HIV infection even in the presence of a high viral load.

    Then there is sickle cell anemia confering resistance to malaria as well. I do not think your guess is wrong, just that the issue is more multi-factorial than people expect, and there we also agree regarding the consequences of climate change. Still, if we can avoid the more severe detriments by simply being more responisble conservationists and using clean alternative energy sources we should definitely do so.

    I agree somewhat on predictions for the future with climate change and even attributions.

    Comment by Jacob Mack — 17 May 2010 @ 6:02 PM

  84. SA, the drought was a period of reduced rainfall that wasn’t unprecedented, or even a record by any shot.

    While one can’t definitively state is wasn’t global warming, one can’t say it definitively was, either.

    Putting all one’s eggs in a weather condition is as wrong as the folks who yelled “fake” this winter due to snow. If we have another cool winter (two in a row!) and rains on par with what’s expected in a normal year will that disprove global warming? Of course not!

    Noting local trend change isn’t invalid in gauging climate. One just has to use caution in not exaggerating it to the point where it is no longer credible or appears to be the primary proof.

    I tell folks that climate change isn’t marked by Biblical style signs and portents. It’s far more insideous and subtle. It’s plants blooming a few days early…and the pollinators not ready for it, meaning reduced yields.

    That’s not nearly as sexy as pointing at Hurricane Katrina and pinning it on global warming, especially since it’s patently a lie to do so. The weasel words of “well, storms may become more intense” as an excuse when the error is pointed out makes it even worse.

    But it is really tempting (and was done) to do just that.

    Ditto every other phenomenon. The Icelandic volcano was NOT caused by global warming. Yet we see silliness and rhetorical nonsense suggesting it was (or, by proximal content, implying it). The oil slick in the Gulf is not going to heat the planet on a global scale. It’s serious enough by itself; no need to borrow trouble that’s not warranted.

    The scientists have done a really good job of trying to mitigate such mistakes by pointing them out (though there is a lot of room for improvement, IMHO), but are hampered by the same ignorance of activists and laymen that is displayed on the “denialist” side of the coin.

    Comment by Frank Giger — 17 May 2010 @ 6:11 PM

  85. By the way, here’s the kind of claims that are being made about the “Pacific Decadal Oscillation” (the one ‘discovered’ in the salmon catch proxy data) by Don Easterbrook:

    [PDO explains everything]

    That’s odd. If you read this interview, Easterbrook seemed to think it was -all- about solar variation, not a thing about the PDO. Now it’s -all- the PDO? Or is it both? Which marbles are we looking for today?

    Comment by Doug Bostrom — 17 May 2010 @ 6:25 PM

  86. Doug (#85),

    I think Easterbrook’s just trying to throw out enough junk at the political show, aiming for quantity (not quality). I don’t think he’s got any published studies on the matter. The “PDO” claim has been his primary bread and butter play, when he’s not drawing up weird graphs that place the LIA 1000+ years before its actual occurrence.

    http://chriscolose.files.wordpress.com/2008/11/easterbrook.jpg

    http://chriscolose.wordpress.com/2008/11/11/easterbrook-and-the-coming-global-cooling/

    Comment by MarkB — 17 May 2010 @ 6:55 PM

  87. “Any critiques of Easterbrook’s claims from realclimate, or does that sound reasonable?” Ike Solem — 17 May 2010 @ 4:44 PM

    Already done

    “The AP interviewed Don Easterbrook, who claimed that “We started the cooling trend after 1998. You’re going to get a different line depending on which year you choose.” According to one of the statisticians, the fact that you have to choose 1998 as your starting point in order to observe a (statistically insignificant) cooling trend is part of the problem.”
    “This is what’s referred to in statistics as “endpoint sensitivity,” and it’s the main reason that climate disruption deniers like Easterbrook can appear and sound so reasonable when they’re actually misusing or misunderstanding the data.”

    Not to mention that if you start in 1999, the trend is up.
    If he is correct about statements 1,2,& 4, despite cocking up 3(hey, 3 outta 4 ain’t bad), then the fact that we are warming is additional evidence for AGW. Be sure to thank him for providing it.

    “Which has me wondering, how many non-temperature indicators are there of AGW? Is there a list?” Richard Hendricks — 17 May 2010 @ 11:46 AM

    Snow cover is declining, disappearing earlier in the spring, and reaccumulating later in the fall. The peak is higher, which may reflect that higher humidity and decreased latitudinal temperature gradients caused by global warming is causing heavier precipitation events [1] which fall as heavy snow when the temperature is cold enough. I downloaded data from http://climate.rutgers.edu/snowcover/ and plotted the normalized snow cover anomaly compared to a 1967-1989 baseline here.

    [1] My area of NC is under a flash flood warming right now; it’s probably just weather, but if Tennessee, Arkansas, Texas, North Carolina, and Italy(it’s rained every day of the Giro di Italia) start flooding every spring, eventually it will become climate.

    Comment by Brian Dodge — 17 May 2010 @ 8:29 PM

  88. Frank @84:
    I agree about the dangers of putting one’s rhetorical case into the “event X was caused by global warming” basket. However we have to deal with the fact that the probablity distribution of the occurrence of many of these phenomena is expected to be seriously modified as a result of warming. And I think a good bit of the human and ecosystem cost of climate change is going to be transmitted via the change in frequency/intensity of extreme events. So we have a real dilemma here, it is important to make the case that the frequency of damging events is increasing because of AGW, while trying to avoid the journalistic/rhetorical trap of attributing any single occurrence to AGW. This isn’t easy in a mathophobic world.

    Finally, you too strongly poo-poo the AGW volcanoe connection. There are paleo studies and theoretical reasons to expect that periods of rapid deglaciation will see an increase in volcanic activity in deglaciating volcanic regions. Conversely during periods of glaciation, it is expected that volcanic activity will be somewhat suppressed. This is similar to the case of hurricanes, where warmer sea surface temperatures are implicated in increased frequency and intensity, but are not a sole factor, so attribution of individual events becomes difficult.

    Comment by Thomas — 17 May 2010 @ 9:14 PM

  89. Jim: Thanks for the response. It could be a temporal lobe problem. See Michael Persinger’s book.

    Comment by Edward Greisch — 17 May 2010 @ 9:20 PM

  90. What can we learn from the last 20-year maximum and minimum?

    I’m puzzled by a picture (well, graphed from the database).
    From this page, follow the pointer linked to the word “website”
    http://www.drroyspencer.com/2009/01/daily-monitoring-of-global-average-temperatures/
    That takes you to this page
    http://discover.itsc.uah.edu/amsutemps/
    Choose, as he suggests, the 14,000-foot (Ch05) chart
    The two greenish lines are for 2009 and for 2010-to-date.
    At the bottom, check the boxes for the 20-year record highs and lows.
    Click ‘redraw’
    Then click in all the years available.
    Click ‘redraw’

    Now try it for the “Near surface (Ch 04).

    It can get confusing, the colors used for each year are different for different elevation/bands.

    Comment by Hank Roberts — 17 May 2010 @ 9:56 PM

  91. Brian Dodge @ 87:

    [1] My area of NC is under a flash flood warming right now; it’s probably just weather, but if Tennessee, Arkansas, Texas, North Carolina, and Italy(it’s rained every day of the Giro di Italia) start flooding every spring, eventually it will become climate.

    Well … we’ve had an exceptionally wet and not-much-sun past 8 months here in Central Texas, but I’m betting we’re experiencing a short-term set-back. Of the past 8 months, total solar radiation (of the kind I can turn into electricity) has been well-below average for 7 of those 8 months. And it isn’t just happening on my roof — I’ve read countless discussions by solar power people who are finding themselves looking for a Force Majeur clause they can use because the sun just ain’t shining as much as it has in the past. I’m 20% =below= where I should be and that’s what I’ve heard from quite a few other people in the biz.

    Comment by FurryCatHerder — 17 May 2010 @ 10:06 PM

  92. Reference Chapter 8 of “Storms of My Grandchildren” which talks about CO2 and temperature going back 65 million years. I am now reading about how methane hydrates [clathrates?] melting kicked the temperature up in the PETM Paleocene-Eocene Temperature Maximum. Dr. Hansen published “Target CO2″ in the The Open Atmospheric Science Journal 2008
    http://www.bentham.org/open/toascj/
    This is where the target CO2 concentration of 350 ppm or less comes from. A target of 280 ppm CO2 would be better from the “What we can learn from studying the last millennium (or so)” article but more difficult to reach.
    I haven’t read far enough to find out when the methane hydrate-clathrate? feedback kicks in.
    Is a hydrate the same as a clathrate? Any comments on the critical conditions for that feedback? Maybe another article? It seems to me that the trigger point for methane release from the ocean bottom is something we want to avoid like 2 or 3 plagues.

    Comment by Edward Greisch — 17 May 2010 @ 10:21 PM

  93. #77 SecularAnimist: “How do you know the drought in Georgia was NOT caused by global warming?” (see also #84 Frank & #88 Thomas)

    Seager et al., J. Climate, http://www.ldeo.columbia.edu/res/div/ocp/pub/seager/SE_drought.pdf

    From the abstract: “…From the perspective of the historical record the recent drought [in the Southeastern United States] that began in winter 2005/6 was a typical event in terms of amplitude and duration….The recent drought, forced by reduced precipitation and with reduced evaporation, has no signature of model-projected anthropogenic climate change.”

    This is from the same lead author who said that the American Southwest was facing a permanent Dust Bowl due to global warming. When he says this was not an AGW drought, I tend to believe him.

    Comment by John N-G — 17 May 2010 @ 10:50 PM

  94. #80 Phillip “increasing toxicity of cassava” – it’s my understanding is that this is a prediction of a consequence of higher CO2 in the future, based on laboratory studies, not a real world observation right now (http://www.abc.net.au/catalyst/stories/2891924.htm)

    Comment by David Horton — 17 May 2010 @ 11:27 PM

  95. re: #58 Jim
    1) If you really want to get into this, you may want to read Carbon pool and biomass dynamics associated with deforestation, land use, and agricultural abandonment in the neotropics, July 2009.
    “Ecosystem C pools of Neotropical primary forests minimally range from ~141 to 571 Mg/ha”. i.e., 141-571 tons/ha.

    50M ha X 141 tons/ha => ~7 GT
    50M ha X 571 tons/ha => ~29 GT
    (and of course, everything around it is more complicated, but at least the order of magnitude is in the ballpark.

    [Response: John, a couple of points. First, their 50 million ha estimate is heavily dependent on pre- and post-contact population estimates, combined with the estimated per-capita amount of cleared forest land used for agriculture (1ha/person)--all three of these are going to have high to very high uncertainties. Second, aside from the wide variations in various primary (i.e. old growth) tropical forest biomass estimates, we are talking about a 34 year sequestration period (1570-1604, the most abrupt decline in Law Dome record), a small fraction of the time required to reach max. carbon. If we use something like 350Mg/ha for primary forest C, and (generously) 25% of Cmax at t=34, you're talking about 7.6ppm * (2.13Gt/ppm)/(0.25 * 3.5 e-7 Gt/ha) = 185 million hectares of required land. That's a LOT of land.]

    2) But, you really want to keep an eye out for the Nevle, et al paper submitted to The Holocene, which is 2+ years later than the 2008 paper I think you are referring to.

    [Response: Definitely--thanks for the heads up.]

    3) It is clear that multiple groups of plausible people are trying hard to get bounds on the multiple sources of uncertainty as to attributions of {reforestration, volcanoes, irradiance changes, feedbacks, and of course timing), and a lot has been going in just the last year or two.

    4) I still think, that for this thread, it makes relatively little sense to debate whether or not this happened (especially if people haven’t tracked references like that, or the earlier Nevle&Bird, or recent Ruddiman work, etc.)

    I still think the interesting question for this is to apply what-ifs back to Mike’s original post and ask if one would expect any differences in regional fingerprints or not.

    [Response: I agree.--Jim]

    Re: temperature scale for Law Dome
    Needless to say, 0-origin atmospheric CO2 scales are not easily found in the literature :-), given that ~180 is about as low as it gets, and since it’s stayed in the 270-285ish band for ~4,000 years. One picks scales so that relevant features are visible but not overemphasized. I suppose I could have started at 250, which would have covered all of human history. If an indicator sticks within a ~5-pt range for 550 years, and then seems to drop ~7 ppm, and then stays 3-4 ppm for 200 more, a chart ought to show that.

    Comment by John Mashey — 17 May 2010 @ 11:41 PM

  96. I just read http://www.realclimate.org/index.php/archives/2005/12/methane-hydrates-and-global-warming/
    and got some of my questions answered.

    Comment by Edward Greisch — 18 May 2010 @ 12:25 AM

  97. “SA, the drought was a period of reduced rainfall that wasn’t unprecedented, or even a record by any shot.

    While one can’t definitively state is wasn’t global warming, one can’t say it definitively was, either.”

    Can you say it would have been as bad if we weren’t warming?

    No.

    In fact the processes involved can be shown to be exacerbated by the current warmer climate.

    If a one-in-a-hundred event starts turning up one-in-ten times, then you KNOW that something has changed. Even though your one-in-a-hundred event is still not unprecedented (it happened before, roughly once every hundred) and it’s nowhere near a record (it would be less severe than a one-in-a-thousand event).

    Denialists throw out the subtlety in making their claims and use it again to throw out explanation of events by the science.

    Comment by Completely Fed Up — 18 May 2010 @ 2:54 AM

  98. The malaria pathogen exists in the Thames Valley in the UK. Mosquitos also exist there. But the climate is too cool for the pathogen to transfer from the mozzies to the human population.

    In a warming climate, this will no longer be the case.

    Sometimes there’s no need for spread.

    Comment by Completely Fed Up — 18 May 2010 @ 2:56 AM

  99. [OT] Edward Greisch #57, on behalf of us innumerate humanities graduates: sorry, we didn’t know we were oppressing you.

    Comment by CM — 18 May 2010 @ 3:23 AM

  100. Re: Hank Roberts,
    Thanks for the reply in the previous post. Given the vast volume of arctic ocean and the relative depth I think I would agree that the ph would indeed stay much the same at least for now. Your comment that at a 1m depth sediment is converted to methane or methane hydrates amongst other compounds is very interesting..cheers!

    Comment by Lawrence Coleman — 18 May 2010 @ 4:26 AM

  101. 73 – Frank Giger. You seem to post here regularly, yet have never heard of the intensification of the hydrological cycle?. Plenty of free papers on the topic available via Google Scholar. Your example seems in line with expectations.

    A very recent paper by Paul J. Durack and Susan E. Wijffels here:

    http://journals.ametsoc.org/doi/pdf/10.1175/2010JCLI3377.1

    Comment by Dappledwater — 18 May 2010 @ 4:45 AM

  102. Ike Solem 78,

    I regressed Hadley dT on ln CO2 and the PDO for 1880-2007. PDO did indeed affect global temperatures, but it only accounted for about 4% of the variance. CO2 accounted for 76%.

    Comment by Barton Paul Levenson — 18 May 2010 @ 5:37 AM

  103. Ike,

    1st message was eaten. PDO accounts for 4% of dT variance 1880-2007. CO2 accounts for 76%.

    Comment by Barton Paul Levenson — 18 May 2010 @ 5:39 AM

  104. Philip Machanick, 80, and Richard Hendricks, 67

    I believe you are talking about indicators of “climate change”, not indicators of “AGW”. If such indicators had ever existed, we wouldn’t need the IPCC to try to sort it out…

    Comment by Naindj — 18 May 2010 @ 5:40 AM

  105. Frank Giger, I understand you to be saying that when the science gives robust predictions that AGW will increase certain types of phenomena, then when those phenomena occur, anyone who suggests that they are in fact being caused by AGW just as the science predicted, has no credibility.

    Have I got that right?

    Comment by SecularAnimist — 18 May 2010 @ 6:32 AM

  106. “anyone who suggests that they are in fact being caused by AGW just as the science predicted, has no credibility.”

    I think that Frank is worse than that: if someone suggests that their severity is caused by AGW, Frank thinks they have no credibility.

    Or it at least seems that’s what he’s saying.

    Comment by Completely Fed Up — 18 May 2010 @ 8:02 AM

  107. Here’s the latest from the Heartland Institute conference, on the Little Ice Age and the current warming – apparently, it’s not the “cooling PDO cycle”, says there expert, it’s the “cooling solar cycle” –

    “Observations of the sun show that as for the increase in temperature, carbon doioxide is ‘not guilty,’” Abdussamatov wrote, “and as for what lies ahead in the coming decades, it is not catastrophic warming, but a global, and very prolonged temperature drop.”

    …As historical support for his theory, Abdussamatov cited the observations in 1893 by the English astronomer Walter Maunder, who came to the conclusion that from 1645 to 1715 sunspots had been generally absent. That period coincided with the middle and coldest part of the Little Ice Age.

    Abdussamatov also observed “the most significant solar event in the 20th century was the extraordinarily high level and the prolonged (virtually over the entire century) increase in the energy radiated by the sun,” resulting in the global warming that today climate alarmists believe is a man-made phenomenon.

    Well, that’s the Heartland Conference for you – ignoring the carbon cycle, refusing to admit that infrared-absorbing gases actually warm the atmosphere, insisting that solar explanations or “ocean cycle” explanations account for all global warming, and assuring everyone that a “major cooling event” is only a decade away. How do they keep a straight face?

    @BPL: “PDO accounts for 4% of dT variance 1880-2007. CO2 accounts for 76%.”

    Reference? Supporting information? Mechanistic explanation of the onset of a “PDO event” along the lines of the onset of an ENSO event, either a La Nina (negative phase) or an El Nino (positive phase)? With ENSO, physical oceanographers have come up with reasonable physical explanations for the onset and collapse of El Nino events – but the other putative multidecadal ocean modes like the PDO and the AMO? Statistical data juggling with a priori assumptions might give you those ‘variance’ numbers but they shouldn’t carry much weight in the absence of valid mechanical explanations – for the ENSO case, here’s an excellent set of lecture slides:

    http://www.ldeo.columbia.edu/edu/dees/V1003/lectures/ENSO/ENSO.2100.pdf

    P.S. here’s the most recent global sea surface temp anomaly maps:
    Atlantic Ocean – if you look back a few weeks, you’ll see that the negative cool pools in the mid Atlantic have warmed to neutral, while conditions in the Atlantic Warm Pool are about +2C, and the northwest Atlantic is also at +2C.

    Pacific Ocean – Warm anomalies persist all across the equator, the southern Pacific, and the northwestern Pacific – with cool anomalies in the western Pacific. (A cool anomaly in the western Pacific! Must be the PDO! Someone see how many salmon they caught this year!). El Nino indicators have fallen to neutral – but what will next year bring? Any predictions for ENSO phases a decade from now? How about “PDO phases”?

    Comment by Ike Solem — 18 May 2010 @ 8:15 AM

  108. “Any predictions on when Black-bellied Whistling Ducks will make it to Canada?”

    Based on the information given, within the decade seems reasonable. . .

    April NCDC numbers are out–warmest April in the instrumental record. Warmest Jan-April, too.

    “It’s just weather”–but it also suggests that 2008 was “just weather” too, not some Easterbrookian “inflection point.” And it’s rather interesting that it continues so warm during such a quiet solar cycle.

    Comment by Kevin McKinney — 18 May 2010 @ 8:20 AM

  109. SA, take a look at post #93 for the paper that actually agrees with me. Another quote:

    “We will conclude that the recent drought was quite typical of historical droughts,
    that winter drought in the Southeast is weakly linked to a cold tropical Pacific Ocean,
    that summer drought is caused largely by internal atmospheric variability and, therefore,
    that there is limited predictability of extended droughts. We will also show that earlier
    centuries had droughts as severe as the recent one but which extended for as long as a
    decade or more. It will also be shown that the recent drought is unlikely to have been
    influenced by anthropogenic climate change
    but that the latter will lead to increased
    precipitation but also increased evapotranspiration with the potential for reduced soil
    moisture and river flow that would place further stress on regional water resources.”

    Phenomena are just that – phenomena. The worst sort of cherry picking can happen if cite every weather event as a demonstration of global warming. It’s not that unusual to have an 18-24 month drought in the SE. Heck, I’ve seen a couple of them (and worse than the last one); to point to this one as the smoking gun lacks credibility. The other option is to claim every weather event as proof of global warming. Equally silly.

    The volcano on Iceland was NOT caused by global warming. That doesn’t mean that melting glaciers don’t effect plate shifting (heck, the Great Lakes are still on the rebound from the last Ice Age ending) and volcanism. But it doesn’t suddenly negate tectonics as the prime mover.

    The analogy is having a friend that can’t even skate suddenly taking up hockey and making the fairly safe prediction that he will pick up an injury in the next six months. And then when one sees a cast on his arm five months later instantly berating him for foolishly taking to the ice, only to find he broke it falling down the stairs leading to rink. The system is sufficiently chaotic to rule out climate models as good predictors of weather – even when they take on long enough durations to imply a trend.

    A better use of projections is my front yard. I’ve been toying with the idea of planting a pair of apple trees, always an iffy proposition in the South. On any given ten year stretch, one can expect it to reach freezing long enough for them to produce apples of any real merit five of them (in my location). However, this is not really realistic if the models hold true; in the future I might only see three years of sufficient freezing out of ten. But I like apple trees, so I’ll probably plant them anyway – and just lower my expectations of how well they’ll bloom on any given year.

    That’s the insideous nature of climate change I’m referring to. It’s more subtle than “it rained/didn’t rain/there was a tornado/there wasn’t a tornado, therefore global warming has arrived” type pronouncements.

    Comment by Frank Giger — 18 May 2010 @ 8:45 AM

  110. Kevin McKinney @ 108:

    “It’s just weather”–but it also suggests that 2008 was “just weather” too, not some Easterbrookian “inflection point.” And it’s rather interesting that it continues so warm during such a quiet solar cycle.

    It’ll be more interesting when we break the ’98 HadCRUT record during such a quiet solar cycle. Because the solar cycle around ’98 weren’t at all quiet …

    And for anyone who wants to look at the progression of SC23 to SC24, here it is — http://users.telenet.be/j.janssens/Spotless/Spotlessallcycles.png

    Comment by FurryCatHerder — 18 May 2010 @ 9:13 AM

  111. John N-G — 16 May 201: Is there any evidence that the MCA departed farther from some suitable multi-millenial mean than other carefully-chosen 500-year intervals?

    I sort of agree with Benson @50 but disagree that it is just a noisy wobble. To my eyes it seems to me that the Holocene is in a long term cooling trend. That would be in-line with the most interglacials. A quick warming up to a peak and then a slide back into the glacial period. Here is Holocene graph of GISP2 data from Greenland. The gray bar is a 2 s.d. range.
    http://rhinohide.cx/co2/img/GISP2-10000.jpg

    Last 2000 years GISP2 with Box 2009 appended.
    http://rhinohide.cx/co2/img/GISP2-2000-Box-2009.jpg
    http://journals.ametsoc.org/doi/abs/10.1175/2009JCLI2816.1

    I’ve been told that I’ve used an older GISP2 data set, so the indicated just years may be off just by a bit.

    Comment by Ron Broberg — 18 May 2010 @ 9:14 AM

  112. Frank Giger,
    I agree 100% that attributing any particular event to “climate” is simply silly. Climate after all, has to do with trends. However, there is a big difference between attribution of a single event to climate change and citing a particular event as typical of those expected to happen more frequently as climate change progresses. I think that is perfectly valid. More valid still would be looking at relative frequencies of particular types of events and how they change.

    And unlike the denialists, we need to be scrupulous about pointing out where there is active research and disagreement–e.g. the likely effects on hurricanes–as opposed to areas where there is broad agreement–e.g. increasing drought in the US Southwest.

    Comment by Ray Ladbury — 18 May 2010 @ 9:29 AM

  113. “We will also show that earlier centuries had droughts as severe as the recent one but which extended for as long as a decade or more. It will also be shown that the recent drought is unlikely to have been influenced by anthropogenic climate change ”

    Frank:

    “If a one-in-a-hundred event starts turning up one-in-ten times, then you KNOW that something has changed. Even though your one-in-a-hundred event is still not unprecedented (it happened before, roughly once every hundred) and it’s nowhere near a record (it would be less severe than a one-in-a-thousand event).”

    To show that AGW is unlikely to have influenced, you’d have to show that the warming that is the result of AGW would have had no effect on the drought.

    Did the paper do that?

    Comment by Completely Fed Up — 18 May 2010 @ 9:34 AM

  114. Thomas (88), you in essence say Frank G is incorrect because you have to convince people of AGW, and throwing a bunch of speculative regional or geophysical changes, whether supported by tight science or not, might be effective, so long as you are careful to not get so specific that even mathophobes can pin you down and show it as unscientific and unsupported. To wit: “…it is important to make the case that the frequency of damging events is increasing because of AGW, while trying to avoid the journalistic/rhetorical trap of attributing any single occurrence to AGW.”

    Comment by Rod B — 18 May 2010 @ 9:34 AM

  115. “Reference? Supporting information? Mechanistic explanation of the onset of a “PDO event” along the lines of the onset of an ENSO event…”

    By correlating the PDO effects against the temperature record.

    Where a 0.04 proportion of effect of PDO will reduce the variations of the temperature graph around a level mean.

    It’s called “maths”.

    Comment by Completely Fed Up — 18 May 2010 @ 9:36 AM

  116. CFU says,
    “…Can you say it would have been as bad if we weren’t warming?

    No.”

    I’ll say it would have been as bad. Prove me wrong.

    Comment by Rod B — 18 May 2010 @ 9:43 AM

  117. FCH “… we’ve had an exceptionally wet and not-much-sun past 8 months here in Central Texas …”

    And the same up in the PNW, which is why I find the relations to PDO and ENSO in this post interesting, I hopehopehope we’re not seeing a trend developing.

    Comment by flxible — 18 May 2010 @ 10:17 AM

  118. “I’ll say it would have been as bad. Prove me wrong.”

    Easy:

    You get droughts when it’s hotter and AGW is causing warmer temperatures.

    Comment by Completely Fed Up — 18 May 2010 @ 11:56 AM

  119. The National Academy of Science of The USA just sent me an e-mail with a link to this page:

    http://americasclimatechoices.org/?utm_medium=etmail&utm_source=National%20Academies%20Press&utm_campaign=NAP+mail+new+05.18.10&utm_content=Downloader&utm_term=

    announcing: “At a public briefing to discuss the reports, Ralph J. Cicerone, president of the National Academy of Sciences, will deliver opening remarks, and members of the panels that wrote the reports will discuss their recommendations and take questions. The briefing starts at 10 a.m. EDT Wednesday, May 19, in the Lecture Room of the National Academy of Sciences building at 2100 C Street, NW, Washington, DC. Those unable to attend the event can watch the live webcast at The National Academies website. “

    Comment by John E. Pearson — 18 May 2010 @ 1:38 PM

  120. But not everywhere. That’s why scientists do regional probabilities.

    My point isn’t to say climate change isn’t happening or that people aren’t having an effect on it. My point is that we should be very careful in describing any one weather or short term (18 month) event as definative proof.

    When we do that we open up the contrary claim when the situation reverses.

    What if the next 18 months have the South slightly above the climate norm? If the drought is trumpeted as the smoking gun, the rain puts it down. We then have to admit that the drought wasn’t due to climate change or worse, completely switch sides and say the rain is.

    Far more credibility is gained if a more intellectually honest approach is taken. As the climate goes into flux, we should see more variance along the normal bands; rather than drought-normal-normal-normal-wet-normal-normal (“normal” being the expected climate within the average) we will start seeing drought-normal-drought-wet-wet-drought-normal. Swings to the edges of the band are actually worse than a straight trend line, btw.

    What the popular narrative in the Southeast missed was that there would be a bounce back from the drought, and when it lifted chances are it would swing to abnormally wet. Indeed, that’s what we saw last year, and particularly in the fall. The rains returned, giving a very good first harvest but then continued, ruining a fair number for the second one as fields were too bogged with mud for combines and they didn’t get taken up in time to be too late. Heck, even hay bailing suffered.

    The smart farmers are already picking up on this. Hay barn size and location is getting a lot of thought. They’re getting bigger and placed on higher ground for better drainage. Ponds for cattle are being increased and how drainage works for the whole of the area is getting a relook – with up and down years for rain taken into account.

    My point once more is that we should use caution in using specific weather events as “proof” of climate change.

    Comment by Frank Giger — 18 May 2010 @ 1:57 PM

  121. IS 107,

    My linear regression is enough to show that the idea that the PDO causes it all and CO2 is insignificant is wrong. I really don’t have to get more sophisticated than that.

    Comment by Barton Paul Levenson — 18 May 2010 @ 1:59 PM

  122. Off-topic, but I just finished writing an expression calculator, a little GUI utility for Windows. Email me if you want a copy of the setup program for the Beta version.

    Comment by Barton Paul Levenson — 18 May 2010 @ 2:03 PM

  123. Please, kids, cite some kind of source for your claims.

    Here’s the _next_ 20 years, slides and audio.
    Invaluable information, reliable source:
    http://sackler.nasmediaonline.org/2007/ile/jeremy_jackson/jeremy_jackson.html

    Comment by Hank Roberts — 18 May 2010 @ 2:12 PM

  124. CFU #113: ““If a one-in-a-hundred event starts turning up one-in-ten times…”

    What about a drought that stands out against the background of the 20th century but is unremarkable by the standards of the previous millennium? (Which kind of links the discussion to the topic of this post.)

    CFU #113: “Did the paper do that?”

    Why don’t you read it and see? (I did, but I won’t spoil it for you.)

    CFU #118: “You get droughts when it’s hotter…”

    … or when it’s raining less. So it gets a little more complicated when AGW affects precipitation and evaporation.

    Comment by CM — 18 May 2010 @ 2:12 PM

  125. Ray Ladbury (112) says, “….citing a particular event as typical of those expected to happen more frequently as climate change progresses” is perfectly valid.

    Might be valid but certainly is neither helpful nor scientific. The only value in doing that is to imply and get the recipient to believe that particular events are the direct result of climate change while being able to deny that is what you said.

    Comment by Rod B — 18 May 2010 @ 3:25 PM

  126. Rod,
    Note that I was very careful to state that one must speak of a trend when discussing climate. However, providing examples to indicate which way the trend is going could be quite helpful pedagogically and is certainly NOT unscientific. Would you consider it inconsistent to state that a particular drought is consistent with an increasing trend of droughts?

    Comment by Ray Ladbury — 18 May 2010 @ 3:53 PM

  127. One hundred years from now the vastly reduced rejectionist community will still be dismissing the latest storm surges washing over the corroded rebar emerging from the shallow embayments where New Orleans or Dhaka used to stand as simply isolated events.

    Forget any single drought, any one precipitation event, any particular tropical cyclone. Any isolated event can be singled out and dismissed as confirmatory data supporting the notion that our climate is changing.

    On the other hand, collections of excursions in locations significantly geographically isolated from one another seem sufficient to conclude there’s a controlling signal behind the noise of events.

    Collapsing volume of ice in the Arctic concurrent with statistical aberrations in record highs versus record lows in CONUS concurrent with more frequent extreme precipitation variances concurrent with accelerating ice loss at the margins of Greenland concurrent with a cooling stratosphere concurrent with statistical shrinkage of the global glacial ice inventory concurrent with thermal ocean expansion and yet again concurrent with perturbed tundra and permafrost are a set of statistical threads comprising a drapery covering a monumental accidental work of humankind. More threads abound; the warp and woof of this fabric is pretty tightly woven.

    Why look at a single fiber of a single thread?

    Comment by Doug Bostrom — 18 May 2010 @ 4:08 PM

  128. “Might be valid but certainly is neither helpful nor scientific.”

    Really?

    “If you keep doing that, you’ll make it bleed”.

    “If you don’t wear your helmet, you could fall off and hurt yourself again”.

    Both seem to be helpful and are citing an event that is typical as a result of the action.

    And how is it not scientific?

    The chance of a molecule in a gas having more than a certain kinetic energy can be related to the boltzmann equation. Typical energies can too. And how these figures change when you change a factor (add a new gas, let some out, warm or cool the gas) can also be expressed scientifically.

    You state a rebuttal with merely the fact that you said “it’s not” as its only argument.

    Do better than this.

    Comment by Completely Fed Up — 18 May 2010 @ 4:09 PM

  129. “What about a drought that stands out against the background of the 20th century but is unremarkable by the standards of the previous millennium?”

    By the standards of the century-level event of the previous millenium? Then the event is not remarkable unless you’ve seen another change that should affect the probabilities to become less likely an event.

    By the standard of “the worst that had happened in the previous thousand years”, then you’re talking a century-return-event becoming as likely as a millenial-return-event. This is significant. If it weren’t, then why aren’t they both century-return-events?

    Comment by Completely Fed Up — 18 May 2010 @ 4:12 PM

  130. “CFU #118: “You get droughts when it’s hotter…”

    … or when it’s raining less. So it gets a little more complicated when AGW affects precipitation and evaporation.”

    But it can rain less whether it is AGW caused or not. Therefore it is not a variant in the proposed query.

    Proposal: RodB: “It would have been no worse if AGW hadn’t happened”.

    Response: CFU: “Warmer weather makes it worse and AGW is making weather warmer”.

    Rain doesn’t come into it because rain doesn’t make drought not happen in warm weather.

    Comment by Completely Fed Up — 18 May 2010 @ 4:15 PM

  131. “My point is that we should be very careful in describing any one weather or short term (18 month) event as definative proof.”

    STRAWMAN!!!

    Nobody is doing that.

    Only you so you can say it shouldn’t be done.

    What IS being done is saying “You see that warm dry horrible thing that happened? Well climate change will cause more such dry warm weather that makes that horrible thing happen happen more”.

    Just because not every shark kills and eats a human doesn’t mean that shark infested waters are safe. Nor does citing a shark attack not make that shark infested water no longer shark infested. Getting rid of the sharks does that.

    Comment by Completely Fed Up — 18 May 2010 @ 4:18 PM

  132. Ron Broberg (111) — Over the Holocene I see an upswing until around 8000 ypb as in
    http://www.globalwarmingart.com/wiki/File:Holocene_Temperature_Variations_Rev_png
    but also for GISP2
    http://www.ncdc.noaa.gov/paleo/pubs/alley2000/alley2000.html

    Millennial averages of GISP2 temperatures are interesting: Up to peak, down a bit, back up to nearly the same peak and then a dramatic plunge for the past 2000 years, the coldest two millennia of the entire Holocene. This last roughly agrees with the orbital forcing of precession, placing the thermal equator furthest to the south around 2000 years ago.

    Comment by David B. Benson — 18 May 2010 @ 4:47 PM

  133. Please pick a different analogy.
    http://www.sciencemag.org/cgi/content/full/299/5605/389?ijkey=PE1mSnaFDXgiE&keytype=ref&siteid=sci%EF%BF%BD%C3%9C

    Comment by Hank Roberts — 18 May 2010 @ 5:00 PM

  134. John, #41, I agree that the Black Death is not likely to have been a major contributor to global temperature drops due to the lack of correspondence with the proxy records.

    One could make a case for the depopulation of Amazonia contributing to the Little Ice Age based on afforestation, as you pointed out, but there may be a flaw here: massive land clearing for agriculture may not have occurred in Amazonia as it did in the Mayan region. The mounds and urban grids that have been discovered in South America tend to be in fertile floodplains more than interior forests.

    The other issue is that Amazon forests do not sequester a lot of carbon on a per acre basis- the figure is around 300 Mt/hectare, far less than what temperate forests hold. And since Amazon inhabitants and their descendants appear to have have practiced slash and burn, the carbon consequences of this are far less than those of industrial logging, which kills competing species and results in far more soil degradation.

    Comment by mike roddy — 18 May 2010 @ 5:13 PM

  135. Oh, CFU, if you’re thinking heat = drought you obviously haven’t spent much time in warmer climes.

    Some of our wettest years have been some of our hottest. You’ve got to walk in rain that’s seventy five degrees to really appreciate it.

    [edit] Pointing to specific weather events and declaring they would be worse or more severe if climate change wasn’t happening is just flat wrong.

    [edit-lets watch the snark]

    Comment by Frank Giger — 18 May 2010 @ 5:45 PM

  136. re Benson 132

    The graph that I found most intriguing is this one:
    http://www.globalwarmingart.com/wiki/File:Ice_Age_Temperature_Rev_png

    A friend of mine states that if AGW prolongs the Holocene interglacial it will be mankind’s greates achievement. He has a point.

    On the other hand, I note that the previous interglacials seemed to have peaked at a slightly higher temp and collapsed back into a glacier state faster than this interglacial. Can slightly higher temps set up conditions which trigger the collapse back into the glacier state? I honestly don’t think anyone knows this answer with any useful degree of certainty.

    Comment by Ron Broberg — 18 May 2010 @ 6:39 PM

  137. Re 123 Hank,
    I use the Feynman method – I walk around screaming and waving my arms until I have THE correct answer. For example, in 2002, my answer was that the Arctic Sea Ice would be substantially seasonal in 2012. All the respectable climate guys said I was crazy, but that was sort of obvious.

    The point is: that still looks like a better number than I could have gotten from the peer reviewed literature at THAT time. It may even be as good a number as you can find in current literature.

    By the by, the answer that I got in 1999, was that fisheries were in deep trouble. Where was the peer reviewed literature? Peer reviewed literature follows problems, it does not lead on them.

    Comment by Aaron Lewis — 18 May 2010 @ 7:13 PM

  138. Ron Broberg says: 18 May 2010 at 6:39 PM

    A friend of mine states that if AGW prolongs the Holocene interglacial it will be mankind’s greates achievement. He has a point.

    Hopefully our descendants 50,000 years from now who would most likely actually be affected by the next stade will remember to thank us, even as the intervening generations ask themselves, “WTF was with my ancestors, that they were such happy-go-lucky destructive sociopaths?”

    Comment by Doug Bostrom — 18 May 2010 @ 7:21 PM

  139. Ron Broberg (132) — Archer & Ganopowski “Moveable Trigger” (2005) [Available from David Archer's publications page.] suggests that the next possible stade (massive ice sheets) is about 50,000 years in the future providing we don’t add much more CO2. It is quite a fine point as to whether or not AGW kept the globe from plunging into a stade starting about 2000 years ago. Careful reading of A&G suggests not, as does Crucifix & Rougier (2009). Bill Ruddiman seems to have some papers forthcoming showing the opposite; I’m looking forward to reading those contributions.

    Comment by David B. Benson — 18 May 2010 @ 8:38 PM

  140. Extreme rain event: From local TV news this morning: A Mercer County farmer planted corn this spring. It washed away. He planted again. It washed away again and his fields are under water now. If it dries out soon enough, he will plant a third time. Eventually, he will run out of money to buy seed.
    I never heard of having to plant the same field 3 times to get 1 crop before. This is the third year in a row of too much rain here. This has been the corn belt for more than a century, but now it seems to be a belt for something else.

    GW means the wind keeps on shifting, so the rain keeps on moving. I think the “keeps on moving” is the answer to “AGW caused which was it? flood or drought?” AGW causes both, and the “where” keeps moving. The wet climate can only stay in one place if the global temperature remains constant. If warming is continuing, obviously the rainy climate is not going to stay in any one place for a long time. Bands of wet climate are moving past you. So bands of dry climate are also moving past you. That is how agriculture can be driven to collapse: The farmer has to have a constant climate so he can decide whether to plant rice or cactus. A changing climate creates chaos for the farmer.

    Comment by Edward Greisch — 18 May 2010 @ 8:55 PM

  141. Re 136: What strikes me about the graphs of ice age temperature records is that they do show such very steep rates of change, both warming and cooling.

    The patterns are not similar to the forcing patterns that result from orbital changes, though the overall causation has been established.

    IMHO this proves beyond reasonable doubt that there exist strong tipping points in the feedback loops, both directions of change. Because of the AGW, the natural tipping point(s) towards cooling will not be passed this time, and there will not be another ice age for a very, very long future (like many millions of years).

    It is really the “anthropocene” era that now begins. Must be very interesting times for the geologists – wittnessing and directly recording such a remarkable transition.

    It is another matter that there probably are still other and different tipping points within the warm new regime our world is entering. Those points we do not yet reliably know, unfortunately.

    OTOH, the discussion of ice ages is mostly a diversion to draw away attention from time scales relevant to current policy wars. Who cares? 100 years into the future is already too long for most people – that being an optimistic view of a family’s lifespan.

    Comment by Pekka Kostamo — 18 May 2010 @ 10:11 PM

  142. Lawrence, don’t forget methane oxidizes to CO2 — I don’t know how fast that happens in water, but probably as fast as it does in air — and the CO2 is what definitely is increasing the ocean pH.

    I don’t know how much difference a change in methane bubbling out will make, but it will definitely _end_up_ contributing to the change in pH of the ocean via CO2.

    And that pH change is utterly predictable and going to reach a troubling point well before the temperature change is going to worry people.

    Google “Jeremy Jackson” “rise of slime” — that coastal real estate may be unattractive due to toxic algae producing nasty stuff in the air long before the sea level rise matters much. It’s already happening many places.

    So I wasn’t saying not to worry; just noting a detail in how it’s happening.

    Comment by Hank Roberts — 18 May 2010 @ 10:40 PM

  143. It would be great to see a post of RC about the Interacademy Council IPCC review. http://reviewipcc.interacademycouncil.net/comments.html

    My points were:
    * The IPCC needs to report more frequently. Interim reports, or even annual updates would be very useful.
    * More focus on possible tipping points. Especially estimates of sea-level rise from glacial melt, and estimates of non-linear responses to warming.
    * More transparency with the process – especially which representatives are making which changes to the finial release.
    * Stop being so conservative. Offer an your analysis, and be prepared to defend it when it gets attacked by the fossil fuel lobby and governments.
    * Work with science communicators. Create a lay-person’s version of the report.

    It’d be great to see RC’s take on the whole thing. I know the review probably isn’t really necessary, but while it’s happening it’s a chance to improve on what we already have. What improvements to the IPCC would RC contributors like to see?

    Comment by naught101 — 19 May 2010 @ 12:16 AM

  144. Hank: My handle on chemistry is not quite adequate to know whether CH4 oxidises to CO2 and then to carbonic acid in seawater and to what effect NaCl have in the equation. or whether it goes straight from CH4 to carbonic acid? I thought there would have to be some lowering of the ph to the CH4. What is unclear also is whether the arctic ocean currents would divert the relatively more acidic water south bypassing the main krill/planckton breeding grounds since the CH4 sediment release is concentrated in a few localised areas?. This to me is a big issue as a compromised krill /planckton breeding ability will have massive effects right through the oceanic food chain. I’ll read your ‘rise of slime right now…
    Side note: the recent volcanic eruptions from iceland’s unpronouncible volcano may well have been caused or triggered by a decreasing ice sheet thickness causing the bedrock and land underneath to actually rise upwards due to less weight from the ice above. This is happening in greenland right now…currently at 1 inch/yr and accelerating. What do you think?

    Comment by Lawrence Coleman — 19 May 2010 @ 12:28 AM

  145. ScienceDaily: Land under Greenland ice sheet rising at accelerated rates, indicating accelerating ice loss: http://bit.ly/Landice

    Comment by Kees van der Leun — 19 May 2010 @ 12:38 AM

  146. “Peer reviewed literature follows problems, it does not lead on them.”

    Uh, the problem of AGW was written in a paper before people had seen it in measurements.

    I think you’re waving your arms around and screaming again…

    Comment by Completely Fed Up — 19 May 2010 @ 2:30 AM

  147. “Oh, CFU, if you’re thinking heat = drought you obviously haven’t spent much time in warmer climes.”

    Oh dear, Frank. Your memory is slipping.

    We’re not talking about heat=drought. We’re talking about a drought that was happening getting worse because it’s warmer.

    Are you REALLY saying that droughts get less severe if you cool the area??? Interesting effect…

    Comment by Completely Fed Up — 19 May 2010 @ 2:32 AM

  148. “Pointing to specific weather events and declaring they would be worse or more severe if climate change wasn’t happening is just flat wrong.”

    Here’s how it works Frank.

    There’s a drought.

    This means not enough rain to replenish near surface water.

    Now if you make it WARMER, there’s more evaporation, yes?

    Now that makes it even drier, doesn’t it? I mean, less water in the ground is a drought, yes?

    So a drought happening is made worse by warmer weather.

    AGW causes warmer weather.

    Therefore AGW makes a drought worse.

    Comment by Completely Fed Up — 19 May 2010 @ 2:35 AM

  149. I guess Frank is OK with drugs in sports, because you can’t point to someone winning having performance enhancing drugs and say that the drugs did that.

    So too RodB and CM.

    All fine with drugs in sports because you can’t point to an event that depends even partially on the effects of a change and say that the change made the event more evident.

    Comment by Completely Fed Up — 19 May 2010 @ 3:10 AM

  150. LC 144 : NaCl has absolutely no influence on oxidizing. Actually if oceans were in steady state, the CO2 equilibrium concentration depends only on the total amount of CO2 in the atmosphere+Oceans, and the CH4 would only matter following its global released amount – whether it is oxidised in water or in the air is immaterial. But it’s more probably a complicated problem including diffusion throughout the volume. But oxidizing CH4 requires.. oxygen, and I doubt that oxygen concentration is very high below the surface, since it must be regenerated by photosynthesis and solar photons are rather rapidly absorbed. So probably most CH4 is released into the atmosphere before being oxidized in water.

    Comment by Gilles — 19 May 2010 @ 3:47 AM

  151. “Lawrence, don’t forget methane oxidizes to CO2 ”

    Maybe a dumb question, but since CH4 -> CO2 leaves H4 out of the picture, and given that pH is all about Hydrogen in solution, are there competing processes acting against each other here? Or would you get more H2O from each CH4 than CO2 therefore exhaust accessible Oxygen making the production of CO2 from methane somewhat self-limiting.

    Comment by Completely Fed Up — 19 May 2010 @ 4:00 AM

  152. I’m interested in the assertion that:

    LIA = low solar + more eruptions, and
    MWP = higher solar + few eruptions

    (to quote, the article says; “Thus we can basically say that the warmer conditions of the Medieval era were tied to higher solar output and few volcanic eruptions and the cooler conditions of the Little Ice Age resulted from lower solar output and more frequent volcanic eruptions.”)

    I’m interested to know how robust this assertion is, and where I might read quantative data from those periods that support the assertion?

    Kind regards,

    Stephen

    [Response: There are up to date reconstructions (which remain somewhat uncertain in the details) available here. - gavin]

    [Response: There are thorough reviews of these issues in both the Third and Fourth Assessment Reports of the IPCC. Google these reports, you can find them online. You can also find some extensive discussion in this review paper by Jones and Mann. -mike]

    Comment by Stephen — 19 May 2010 @ 4:04 AM

  153. CFU, one question is whether there is an increasing frequency of warming-associated events consistent with the models. Another is whether they arise in the same way as in the models, which would tend to strengthen attribution. None of this can be argued from first principles.

    On the first question, the logic in your #129 is OK. But instead of speculating on how unusual the recent Southeast US drought might be, you could read the Seager et al. paper that was linked to at #93:

    The tree ring records show long periods of severe droughts that dwarf the turn-of-the-century drought in their persistence. (…) Curiously the early and mid 19th Century also appears as a long period of drier conditions after which the Southeast transitioned to a 20th Century that was noticeably wetter than the long term mean of the millennium.

    On the second question, the logic in your #130 is wrong. It’s drought we’re talking about; of course rain comes into it. The Seager et al. paper, again, makes the following point: Models predominantly expect more precipitation, but even more evaporation, hence some net drying. This would be the man-made signature. Recent Southeast drought, however, appears to have been driven by a decrease in precipitation with no increase in evaporation. So it lacks the signature.

    Comment by CM — 19 May 2010 @ 4:21 AM

  154. Dr. Mann–

    Morano’s site claims the earth is heading for a cooling. Pravda is claiming an ice age is coming. http://english.pravda.ru/science/earth/106922-0/

    That Heartland conference is saying exactly what the government-controlled Russian media is saying. Pravda even quotes Inhofe in the citation below.

    Because the KGB and the oil and gas companies put their guys in the Kremlin, “conservative” U.S. Senator Inhofe, his former aid Marc Morano, and Attorney General Cuccinelli are in the same camp as the sensationalist Russian “girlie” tabloid Pravda [See 'Climategate' Exposes the Global Warming Hoax (11-30-09)], the Kremlin-controlled Russia Today T.V. channel, known as RT, which churns out English-language “Climategate” propaganda by the notorious conspiracist Alex Jones and other prominent deniers [See RT's Youtube of Alex Jones on "Climategate: Hoax of all time a global Ponzi scheme"], and the conspiracist 9-11 Truther publication The Rock Creek Free Press, whose delusional editor Matt Sullivan promotes a variety of anti-government junk science conspiracies, such as the claim that “Climategate” is the “Science Scandal of the Century.”

    Links:

    http://legendofpineridge.blogspot.com/2010/05/leading-scientists-publish-open-letter.html

    This is a lot like the KGB propaganda campaign about crafty US scientists making AIDS to kill blacks.

    You climate scientists were defended by Dr. Sagdeev who blew that lie out of the water. You should tell people about what he did because what is happening to you is the same.

    Comment by Snapple — 19 May 2010 @ 6:21 AM

  155. I would not be surprised if RT (Russia Today) covers the Heartland conference.

    Comment by Snapple — 19 May 2010 @ 6:22 AM

  156. Naindj #104: how is ocean acidification being caused by climate change? to Glacier retreat is of course indicative of warming not AGW specifically but if it’s not AGW, what is the cause of warming? It is a counter to those who claim warming isn’t real, it’s instrument error.

    Comment by Philip Machanick — 19 May 2010 @ 6:29 AM

  157. “146
    CM says:
    19 May 2010 at 4:21 AM

    CFU, one question is whether there is an increasing frequency of warming-associated events consistent with the models.”

    CM, no, the question is: when there is a drought, how does the temperature affect it.

    And the answer to that is that the hotter it is, the worse the drought.

    Stating anything different is so bad it’s not even wrong.

    Comment by Completely Fed Up — 19 May 2010 @ 7:14 AM

  158. ” Completely Fed Up says:
    Your comment is awaiting moderation.
    19 May 2010 at 2:30 AM

    “Peer reviewed literature follows problems, it does not lead on them.”

    Uh, the problem of AGW was written in a paper before people had seen it in measurements.

    I think you’re waving your arms around and screaming again…”

    Can I point to the posters own words on this:

    “137
    Aaron Lewis says:
    18 May 2010 at 7:13 PM

    Re 123 Hank,
    I use the Feynman method – I walk around screaming and waving my arms”

    Comment by Completely Fed Up — 19 May 2010 @ 7:17 AM

  159. Also of interest from ScienceDaily: kudzu, “the vine that ate the Southeast”–now found as far north as Pennsylvania and New York, with even an outlying patch near Leamington, Ontario, according to Wikipedia–has been shown to produce ground-level ozone at levels significant for human health.

    As such, its expansion is both a consequence of observed warming–since kudzu can’t survive hard freezes–and a contributor to warming, since O3 is a GHG. (Don’t know if it’s at all significant–anybody know the CO2e of O3? I poked around a bit to find it, but had no success so far.)

    http://www.sciencedaily.com/releases/2010/05/100517172302.htm

    Comment by Kevin McKinney — 19 May 2010 @ 7:24 AM

  160. CM here it is again:

    “116
    Rod B says:
    18 May 2010 at 9:43 AM

    CFU says,
    “…Can you say it would have been as bad if we weren’t warming?

    No.”

    I’ll say it would have been as bad. Prove me wrong.”

    “118
    Completely Fed Up says:
    18 May 2010 at 11:56 AM

    Easy:

    You get droughts when it’s hotter and AGW is causing warmer temperatures.”

    There is already a drought. AGW would make it worse than if there was no AGW because AGW means warmer global climate.

    Making it warmer makes a drought worse.

    Comment by Completely Fed Up — 19 May 2010 @ 7:39 AM

  161. “104
    Naindj says:
    18 May 2010 at 5:40 AM

    I believe you are talking about indicators of “climate change”, not indicators of “AGW”.”

    AGW IS climate change. Therefore any indicator of AGW is an indicator of climate change, because AGW is climate change.

    Your complaint is rather like complaining that investigations into mortality rates is not an indication of mortality rates but indicators of how many people are dying.

    Comment by Completely Fed Up — 19 May 2010 @ 7:42 AM

  162. Link to the Lerdau paper on kudzu and ozone:

    http://www.sciencedaily.com/releases/2010/05/100517172302.htm

    The unusual physiological combination of moderate to high emissions of isoprene and a high N-fixation capacity able to double soil NO fluxes in Georgia makes kudzu a unique source of the key precursors to tropospheric ozone in the United States; it may be as close to a “polluting plant” as one can find. In addition, kudzu’s vine growth form and its ability to fix nitrogen—a combination of traits common among tropical plants but largely absent from vines commonly found in the United States—are likely to allow it to increase its rate of spread and to expand northward as atmospheric CO2 concentrations and winter temperatures increase in coming decades. Vines in general have shown larger and more sustained growth responses to increased CO2 than trees have (30), and the growth responses of N-fixers such as soybean have shown little acclimation to elevated CO2 (31). Currently, winter temperatures seem to define the northern boundary of kudzu’s distribution, possibly as a result of freezing induced embolisms (32). As it is released from these limits on its growth and spreads, kudzu invasion is expected to extend northward by hundreds of kilometers (33); an observed trebling in the number of populations on Long Island, NY, and the recent discoveries that kudzu is established as far north as Maine and Ontario may represent early evidence of that expansion (33, 34).

    Still curious about the net GH effect of this biogenic ozone. Still don’t have a CO2e, and in any case the picture is a bit complicated: O3 is a GHG, but also contributes to breakdown of methane due to reactions which produce free radicals. So the net effect of ozone presumably will be dependent upon CH4 concentrations locally. Also, the effect–whatever it is–is going to be strongly seasonal, with ozone production occurring primarily during the warmer parts of the year.

    Comment by Kevin McKinney — 19 May 2010 @ 7:50 AM

  163. Dang, that was the link to the press release, not the PDF of the paper. Sorry. Trying again:

    http://www.pnas.org/content/early/2010/05/12/0912279107.full.pdf+html

    . . . there we go.

    Comment by Kevin McKinney — 19 May 2010 @ 7:52 AM

  164. Guys, on the website, specificclick is running dog slow. Sitemeter often does too.

    It’s counterproductive: http://ask.slashdot.org/article.pl?sid=07/08/17/1617259

    Comment by Completely Fed Up — 19 May 2010 @ 8:04 AM

  165. Philip Machanick,

    I just wanted to clarify, because this is a usual confusion, and also because I may have missed something, so please correct me if you think I’m wrong. (that would not be the first time!)
    All these events or measurements show that there is a recent warming, clearly. And you are right saying that it is “a counter to those who claim warming isn’t real, it’s instrument error”. But without any further explanation or theory, this is it. To link all this to human activities (the “A” in AGW) you need far more and this is why there are all these debates (Hockey Stick and MWP, cliamte sensitivity and feedbacks, etc…)
    Acidification is a separate issue. As far as I could understand this has very little to do with AGW (neither climate change, you are right). Both are supposed to have the same origin: excessive atmospheric CO2 content, due to human emissions.

    Comment by Naindj — 19 May 2010 @ 9:24 AM

  166. Completely Fed Up, 161:

    No my complaint is rather like complaining that investigations into mortality rates is not an indication of suicidal rates.

    Comment by Naindj — 19 May 2010 @ 9:36 AM

  167. “149.I guess Frank is OK with drugs in sports, because you can’t point to someone winning having performance enhancing drugs and say that the drugs did that.”

    1. No, I’m not okay with it.

    2. You hit on a perfect analogy. Let’s say a biathon athelete is using steroids to improve his time. It will certainly improve his skiing, but not his shooting, as steroids don’t improve the fine motor skills required. To say that performance enhancing drugs effected his ability to hit a bull’s eye on any given squeeze of the trigger is tenuous and influenced on the periphery.

    The same is true here. The drought in question, as demonstrated by peer-reviewed scientific research wasn’t caused by global warming.

    Now either you accept the peer-reviewed science on the matter or you don’t.

    At the risk of sounding snarky, I’ll stick with the scientists on this matter.

    You are free to deny their finding, of course.

    Comment by Frank Giger — 19 May 2010 @ 10:44 AM

  168. Hello. It seems to me that by using your studies we may be able to come up with regional differences during certain time periods. By using this we may be able to determine what the predominate longwave pattern or jetstream pattern was during these time periods. This then would help us today helping with regional differences and warming. IMHO.

    Comment by Ani — 19 May 2010 @ 10:52 AM

  169. Per #5, I wonder if you can provide a copy or URL for the pseudoproxies you used? Of course it’s difficult to recreate these on my own.

    [Response: see the supplementary online information (e.g. here) for Mann et al (2007) for an extensive array of pseudoproxy networks of varying size and spatial distribution and varying signal-to-noise ratios and noise attributes. -mike]

    Comment by Jeff Id — 19 May 2010 @ 11:03 AM

  170. Naindj
    CO2 explains both unusual fast warming and unusual fast ocean pH change.
    Nothing else known is sufficient to explain either change.
    To believe that some unknown hidden cause is credible requires a second unknown hidden cause that would subtract the known effect of CO2.

    http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch9s9-es.html
    Warming is radiation physics.

    http://scholar.google.com/scholar?q=ocean+ph+change
    Ocean pH change is simple chemistry.

    http://scholar.google.com/scholar?hl=en&q=rise+of+slime+“Jeremy+Jackson”
    Biological changes are already far advanced, huge losses documented.

    Comment by Hank Roberts — 19 May 2010 @ 11:26 AM

  171. Global cooling cycle? What global cooling cycle?

    April 2010 the hottest April on record: WMO

    Geneva (AFP) May 18, 2010
    April 2010 was the hottest April ever recorded, with an average temperature of 14.5 degrees celsius (58.1 degrees Fahrenheit), the UN weather agency said Tuesday.

    Citing data from the US National Oceanic and Atmospheric Administration, the World Meteorological Organisation said that the average temperature on both land and ocean this April reached 0.76 degrees Celsius above that of the 20th century average of 13.7 degree Celsius.

    I wonder what the Heartland Conference attendees make of that…

    Comment by Ike Solem — 19 May 2010 @ 11:42 AM

  172. > Re 123 Hank [Please, kids, cite some kind of source....]

    > CFU
    > I use the Feynman method – I walk around screaming and waving my arms

    Feynman: real person, with a real publication record, a trusted source whose work can be looked up by anyone. Like the Contributors here, Feynman could say things and be trusted, because they could be verified.

    You? Please, cite some kind of source. Assertions of belief without citation — even when I likely could find support for them if I did the homework — aren’t credible to new readers without lots of background.

    Comment by Hank Roberts — 19 May 2010 @ 11:43 AM

  173. “1. No, I’m not okay with it.”

    But why? You can’t prove that those drugs improved his performance then, since they could have been ineffective.

    “The drought in question, as demonstrated by peer-reviewed scientific research wasn’t caused by global warming.”

    We aren’t talking about it being CAUSED BY AGW.

    Did you not read? It’s been down here about a half dozen times.

    Here it is again:

    Has the drought event THAT HAS TAKEN PLACE been made WORSE by AGW.

    Yes.

    How?

    Because warmer weather makes a drought WORSE.

    There’s no paper showing this for the same reason there is no paper showing that turning on my electric kettle caused the water to boil.

    Comment by Completely Fed Up — 19 May 2010 @ 11:45 AM

  174. Namjd, AGW is climate change. If there’s no climate change, there’s no AGW. Therefore to prove AGW you have to prove climate change.

    Therefore evidence for AGW is evidence of climate change.

    Comment by Completely Fed Up — 19 May 2010 @ 11:46 AM

  175. ““149.I guess Frank is OK with drugs in sports, because you can’t point to someone winning having performance enhancing drugs and say that the drugs did that.”

    1. No, I’m not okay with it.”

    Really? Can I point you to your earlier statement:

    “Pointing to specific weather events and declaring they would be worse or more severe if climate change wasn’t happening is just flat wrong”

    Now, lets try a little substitution:

    Pointing to specific track events and declaring that they would have changed if drugs hadn’t been taken is just flat wrong.

    AGW (climate change) creates warmer weather. Performance enhancing drugs enhance your performance at track events.

    Warmer weather makes drought more severe. Enhanced performance makes your time in a track event quicker.

    Droughts are made more severe if you increase temperatures. Your winning time is reduced if your performance is better.

    Therefore saying that AGW (climate change) made a drought worse is flat out wrong. Therefore saying that performance enhancing drugs decreased the winning time is flat out wrong.

    How do you manage to call one flat out wrong but not the other?

    You must be disagreeing with one of the intermediate steps leading to the conclusion.

    Which one?

    Comment by Completely Fed Up — 19 May 2010 @ 11:54 AM

  176. “To link all this to human activities (the “A” in AGW) you need far more ”

    We have CO2 from human sources. (anthropogenic)

    We have cooling stratosphere. (climate change)

    We have quicker warming at high latitudes. (climate change)

    We have quicker warming at night. (climate change)

    So complaining that evidence is merely evidence of climate change is falsely accusing: it HAS to be evidence of climate change.

    So what then is causing the climate change?

    Comment by Completely Fed Up — 19 May 2010 @ 11:58 AM

  177. messed up limks at my post at 87
    “the trend is up” should point to http://www.woodfortrees.org/plot/hadcrut3vgl/from:1999/plot/hadcrut3vgl/from:1999/trend/plot/uah/from:1999/trend

    and the snow cover anomaly plot is http://www.imagenerd.com/show.php?_img=sno_cover_anomaly-gZZqa.jpg

    Comment by Brian Dodge — 19 May 2010 @ 12:19 PM

  178. “> CFU
    > I use the Feynman method – I walk around screaming and waving my arms

    Feynman: real person, with a real publication record”

    I know.

    Also, did you notice who said what there? CFU didn’t say that.

    Please check your sources.

    “You? Please, cite some kind of source.”

    Yup, here it is:

    http://www.realclimate.org/index.php/archives/2010/05/what-we-can-learn-from-studying-the-last-millennium-or-so/comment-page-3/#comment-174950

    Quote:

    “137
    Aaron Lewis says:
    18 May 2010 at 7:13 PM

    Re 123 Hank,
    I use the Feynman method – I walk around screaming and waving my arms until I have THE correct answer.”

    My cite for the quote.

    Please cite your source for me saying what you seem to be quoting me as saying.

    Comment by Completely Fed Up — 19 May 2010 @ 12:35 PM

  179. 171: Ike Solem wonders what the Heartland Conference attendees make of that…

    April 2010 was the hottest April ever recorded, with an average temperature of 14.5 degrees celsius (58.1 degrees Fahrenheit), the UN weather agency said Tuesday.

    Uhhhh …. Crappy thermometers? No. Gimme a sec, I’ve got it. THe UN. Aren’t they part of the IPCC?

    Comment by John E. Pearson — 19 May 2010 @ 12:54 PM

  180. Ray, No, I have no problem with trends as long as they are statistically significant from a climate perspective. The Iceland volcano, e.g., isn’t; Katrina, e.g., is a long way from statistically significant; as is one minor specie migrating a bit north, e.g.

    Comment by Rod B — 19 May 2010 @ 12:59 PM

  181. NAS releases three reports on climate change today, one of them including this gem:

    Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. Such conclusions and theories are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities.

    STRONG EVIDENCE ON CLIMATE CHANGE UNDERSCORES NEED
    FOR ACTIONS TO REDUCE EMISSIONS AND BEGIN ADAPTING TO IMPACTS

    Notice that NAS has activated its caps-lock key, which coming from this conservative and rhetorically parsimonious organization is quite an event in itself…

    Comment by Doug Bostrom — 19 May 2010 @ 1:01 PM

  182. John E. Pearson says: 19 May 2010 at 12:54 PM

    Uhhhh …. Crappy thermometers? No. Gimme a sec, I’ve got it. THe UN. Aren’t they part of the IPCC?

    No, it’s because Al Gore is fat. Blog science tells us so.

    Comment by Doug Bostrom — 19 May 2010 @ 1:04 PM

  183. “Has the drought event THAT HAS TAKEN PLACE been made WORSE by AGW.

    Yes.”

    Wrong. NO. No, it wasn’t. Read the research. It wasn’t impacted either way by climate change. It was in the normal variance of historical climate and had NONE of the earmarks of Global Warming.

    Not every weather event – even ones that make a very statistically noisy 18 month long one – is tied to Global Warming.

    You’re such a zealot that you can’t budge from your beliefs when the science is clearly proving you wrong.

    Who’s the denalist here? Look in the mirror.

    Comment by Frank Giger — 19 May 2010 @ 1:10 PM

  184. Yup, I should’ve said
    > CFU
    >> Adam Lewis
    Same point because I’m saying this generally: waving arms is credible for people we can trust but verify by looking at their publications.

    Assertions of belief without sources won’t help readers who can’t know who to trust and can’t verify.

    http://scholar.google.com/scholar?q=how+to+know+who+to+trust%3F

    It’s not my site and I’m not a moderator; what they allow is what we get. Try to be effective, people. Being right isn’t enough. You need to be convincing.

    Comment by Hank Roberts — 19 May 2010 @ 1:15 PM

  185. re ozone in the troposphere and methane in the water column
    “According to new calculations, methane’s effect on warming the world’s climate may be double what is currently thought. The new interpretations reveal methane emissions may account for a whopping third of the climate warming from well-mixed greenhouse gases between the 1750s and today. The IPCC report states that methane increases in our atmosphere account for only about one sixth of the total effect of well-mixed greenhouse gases on warming.

    Part of the reason the new calculations give a larger effect is that they include the effect methane has on air pollution. A major component of air pollution is near-surface-level or tropospheric ozone, which is not directly emitted, but is instead formed chemically from methane other hydrocarbons, carbon monoxide and nitrogen oxides. The IPCC report includes the effects of tropospheric ozone increases on climate, but it is not attributed to particular sources. By categorizing the climate effects according to emissions, Shindell and colleagues found the total effects of methane emissions are substantially larger. In other words, the true source of some of the warming that is normally attributed to smog is really due to methane that leads to increased smog.”
    http://www.nasa.gov/vision/earth/lookingatearth/methane.html

    “Small numbers of instantaneous rate measurements are difficult to interpret in a dynamic, advecting coastal environment, but combined with the concentration and stable isotope measurements, they do offer insights into the importance of methanotrophy[1] as a control on methane release. Fractional oxidation rates ranged from 0.2 to 0.4% of amb- ient methane per day in the deep water (depths >370 m), where methane concentration was high (20–300 nM), to near-undetectable rates in the upper portion of the water column (depths <370 m), where methane concentration was low (3–10 nM). Methane turnover time averaged 1.5 yr in the deep water but was on the order of decades in the upper portion of the water column."
    http://dx.doi.org/10.1016/S0016-7037(01)00625-1

    [1]methanotrophy – microbial methane oxidation – isn't necessarily dependent on oxygen. see http://www.amethox.com/ "Anaerobic methane oxidation is an enigmatic process that was first discovered in 1974." and http://www.nature.com/nature/journal/v464/n7288/full/nature08883.html "This apparently anaerobic, denitrifying bacterium encoded, transcribed and expressed the well-established aerobic pathway for methane oxidation, whereas it lacked known genes for dinitrogen production. Subsequent isotopic labelling indicated that ‘M. oxyfera’ bypassed the denitrification intermediate nitrous oxide by the conversion of two nitric oxide molecules to dinitrogen and oxygen, which was used to oxidize methane."

    I messed up the limks at my post at 87
    "the trend is up" should point to http://www.woodfortrees.org/plot/hadcrut3vgl/from:1999/plot/hadcrut3vgl/from:1999/trend/plot/uah/from:1999/trend
    and the snow cover anomaly plot is http://www.imagenerd.com/show.php?_img=sno_cover_anomaly-gZZqa.jpg

    Comment by Brian Dodge — 19 May 2010 @ 1:20 PM

  186. 176, CFU: So what then is causing the climate change?

    Except possibly for people already committed to one belief or another, that is a most interesting question.

    Is it related to the (yet to be confirmed) discovery that the rate of sea level increase has declined over the last 100 years? And if so, then how?

    Comment by Septic Matthew — 19 May 2010 @ 1:27 PM

  187. “Katrina, e.g., is a long way from statistically significant; ”

    Katrina and 50 other hurricanes however could be.

    PS you haven’t countered your post #116′s rebuttal in post #118. Since you’re the one who answered the query, you at least should know what the query was (since you answered it).

    Comment by Completely Fed Up — 19 May 2010 @ 1:29 PM

  188. http://www.newscientist.com/special/living-in-denial

    ” The first thing to note is that denial finds its most fertile ground in areas where the science must be taken on trust…. global warming … must be taken on trust, usually on the word of scientists”

    http://www.newscientist.com/article/mg20627606.100-living-in-denial-why-sensible-people-reject-the-truth.html

    Comment by Hank Roberts — 19 May 2010 @ 1:30 PM

  189. “and I doubt that oxygen concentration is very high below the surface, since it must be regenerated by photosynthesis”

    Extremeophiles. Anaerobic options. Outgassing. Diffusion from higher layers. And overturning (of which the El Nino/La Nina systems are merely one example, the North Atlantic Conveyor another, and one that runs up the west coast of Canada, etc).

    Comment by Completely Fed Up — 19 May 2010 @ 1:32 PM

  190. JEP (#179), nah, just Heat Island Effect (just wait till Watts writes his paper…). Oh, and show the RAW data!!!

    I.e. Business As Usual.

    Comment by Completely Fed Up — 19 May 2010 @ 1:33 PM

  191. BPL @ 121:

    My linear regression is enough to show that the idea that the PDO causes it all and CO2 is insignificant is wrong. I really don’t have to get more sophisticated than that.

    Right, but the fact that you got 76% for CO2 means that you need to say what the rest is. Because otherwise “the rest” is going to be asserted to be whatever is causing the current changes, and that’s all that care about.

    Like American companies and their fixation on quarterly results, long-term profitability be damned.

    Comment by FurryCatHerder — 19 May 2010 @ 1:38 PM

  192. FurryCatHerder (191) — Here is a way of explaining the rest of the variance as internal variability:
    http://www.realclimate.org/index.php/archives/2010/03/unforced-variations-3/comment-page-12/#comment-168530

    Comment by David B. Benson — 19 May 2010 @ 3:08 PM

  193. #171, 179 — recent hot times might be tough to blame on UHI or the UN. The satellite-based RSS and UAH series both show this April as 2nd-warmest April in their records — and March 2010 the 1st-warmest March.

    Comment by Ambler — 19 May 2010 @ 3:09 PM

  194. 186 Septic Matthew :Except possibly for people already committed to one belief or another, that is a most interesting question.

    You mean except for yourself, yes?

    You already seem to be convinced that there’s no problem with anthropogenic sources of greenhouse gases.

    “Is it related to the (yet to be confirmed) discovery that the rate of sea level increase has declined over the last 100 years?”

    No, because you can’t relate something to an effect that hasn’t yet been discovered.

    It also has no bearing on what’s causing the majority of the warming: sea levels are rising. Ice is melting.

    [edit]

    Comment by Completely Fed Up — 19 May 2010 @ 3:57 PM

  195. Fred: “Wrong. NO. No, it wasn’t.Read the research. ”

    So where is the research you’re citing, Frederick?

    “It wasn’t impacted either way by climate change.”

    So warming has nothing to do with droughts???

    Really?

    “It was in the normal variance of historical climate and had NONE of the earmarks of Global Warming.”

    What are the earmarks of Global Warming?

    Warming, isn’t it?

    Are you saying that global warming CANNOT and NEVER affect droughts?

    Really?

    How does evaporation work on your world, Frank? Does it go up when it cools?

    Comment by Completely Fed Up — 19 May 2010 @ 4:00 PM

  196. CFU says, “…Katrina and 50 other hurricanes however could be statistically significant…”

    Or not.

    Comment by Rod B — 19 May 2010 @ 4:01 PM

  197. @ Mr. McKinney and the kudzu:

    This is pretty big, as anyone who has dealt with the stuff knows. There are only two decent ways to control kuzu – cattle grazing and machete, and only one way to kill it, a pickaxe to find and destroy the crown root.

    I say “decent” because the volume of herbicides required to kill kudzu makes one wonder if the cure isn’t as bad as the ill due to runoff into the water table.

    A particularly nasty second order effect of warming that I do not wish on our Yankee friends.

    Comment by Frank Giger — 19 May 2010 @ 4:10 PM

  198. No, it *IS* “could be”.

    With 50 events it is DEFINITELY possible to draw statistically valid conclusions from the dataset. Depending on rarity, three is enough. If you have three one-in-a-century storms in three years, the chance of this being a statistical clustering is about 1-in-10,000. This is pretty solid statistically).

    Comment by Completely Fed Up — 19 May 2010 @ 4:23 PM

  199. Look, moderator, why do you continue to let through people giving irrelevant statements but splash loads of edits on me?

    CM, Frank and Rod have ALL said “the drought was not caused by global warming” in a argument thread about whether a drought was worsened by global warming. NOT CAUSED.

    Apparently being irrelevant isn’t too much of a problem there…

    [lets just do our best to keep this civil, ok? that will work out in everyone's favor. -moderator]

    [you are the last one with any right to complain about edit policies here--you've been extended an enormous amount of latitude given your attitude. start your own blog if you don't like it here--moderator 2]

    Comment by Completely Fed Up — 19 May 2010 @ 4:26 PM

  200. So, Septic, what do YOU say is causing the warming? You seem to have missed that out, leaving it to just insinuation and half-statements.

    Comment by Completely Fed Up — 19 May 2010 @ 4:27 PM

  201. Ambler, #193, however to turn a radiant intensity into a temperature reading at the surface you require a COMPUTER MODEL!!!

    Ergo, it’s wrong.

    (it’s easy to deny evidence as long as you don’t sweat changing your tune whenever convenient)

    Comment by Completely Fed Up — 19 May 2010 @ 4:29 PM

  202. 200, FCU: So, Septic, what do YOU say is causing the warming?

    I don’t know. I am not sure that the “warming” is ongoing or paused, and I expect that, because I am 63, I may never know.

    The blog called “climateprogress” had a proposal based on stabilization wedges about a year ago, but I didn’t read it until yesterday. I support investments in stabilization wedges because (a) they are mostly justifiable on multiple grounds, not just AGW and (b) since AGW might be true, it’s worthwhile to continue with some reasonable preparations.

    Comment by Septic Matthew — 19 May 2010 @ 4:52 PM

  203. Frank Giger says: 19 May 2010 at 4:10 PM

    I say “decent” because the volume of herbicides required to kill kudzu makes one wonder if the cure isn’t as bad as the ill due to runoff into the water table.

    Veering wildly off-topic… It’s not really a scalable solution but I found that a truly tiny amount of RoundUp injected directly into the plant with a syringe will crisply and emphatically kill a enorumous specimen of Kudzu. Just a few mils will do it. I could never bring myself to spray the stuff willy-nilly.

    Comment by Doug Bostrom — 19 May 2010 @ 4:55 PM

  204. Completely Fed Up — I find I need to skip over your posts. Please reconsider your overall writing style.

    Comment by David B. Benson — 19 May 2010 @ 5:05 PM

  205. Slightly snarky of me, perhaps, Rod B, but I have to rejoin that Katrina was certainly quite significant, thank you, in a number of statistical areas–like mortality and economic loss and demographic structure (which seems to have been more-ore-less permanently altered.)

    So the lack of attribution of Katrina to AGW is duly noted–but the episode is still a great example of what we may reasonably expect the future to hold under BAU scenarios. (And, sadly, even under more optimistic ones than BAU.)

    Comment by Kevin McKinney — 19 May 2010 @ 5:22 PM

  206. re: kudzu, statistics, etc

    1) Global Change and Invasive Plants in Canada is a nice study by U of Toronto folks on the Northward march of kudzu. Se p.12 and pp.26-, with nice maps, relationships to temperature, etc.

    Not only do warmer winters let kudzu thrive, but it loves higher CO2.

    2) It is *much* easier to generate statistically-significant results from huge samples (like the geographical spread of things inhibited by cold that no one wants, like kudzu or bark beetles) than of relatively rare events like big floods and hurricanes.
    if people haven’t read IPCC AR4 WG II, Chapter 1, to see the vast number of indicators.

    Comment by John Mashey — 19 May 2010 @ 5:59 PM

  207. CFU, go to post 93 for the study showing the drought was both within historical norms and had no markings of global warming forcing.

    When one sees increased evaporation and decreased rainfall it throws up a big red flag – as that is a really big marker for climate change.

    The drought in the SE USA didn’t display any of the markers that usually show when the climate itself is being altered.

    If you’re looking for 100% certainty in climate science, you won’t find it. That’s a bar set too high – and one usually put there by the other side of the arguments.

    @ Mr. Mashey: Yep, I agree that the slowly moving frost line allowing kudzu and other terrible stuff is far more persuasive in demonstration of climate change than a storm. We’ve all seen storms, including terrible ones. Floods aren’t new, either. But when one sees something new, something that couldn’t be there before due to cold, it is very powerful.

    @ Mr. Bostrom: Dang, I wish I’d of known that before going after a patch with machete and pickaxe!

    Comment by Frank Giger — 19 May 2010 @ 8:02 PM

  208. This discussion on droughts is getting out of hand. With AGW and climate change in general there are regions that are usually hot and prone to droughts that will in fact become more moist due to localized weather and microclimate variations. We cannot just assume that there is or there will be worse droughts everywhere it is hot and dry to begin with due to changes in climate. Of course it is not unreasonable to assume this, but as we have seen over the last few decades alone the outcomes are not always what they are thought to be or ought to be. As the IPCC report states droughts may become worse,but rainfall and overall precipitation may increase in some regions as well. Recent studies have also shown that some crops thrive during hotter and dryer conditions. This is shown empircally in nature and in contrived experiments over the past several decades as recently highlighted in Scientific American.

    Oh on the CH4 issue in water; no not a serious issue. The oxidation of CH4 to C02 is more of favorable reaction in the atmosphere.

    Comment by Jacob Mack — 19 May 2010 @ 8:05 PM

  209. You guys do realize that even with a quantum computer we could not really predict many aspects of climate over the next 10-30 years. We can, however, make some good approximations: a low middle and high end time and qualitative estimate with some numerical figures that can be relatively accurate.

    Comment by Jacob Mack — 19 May 2010 @ 8:07 PM

  210. # 206 John Mashey so very true. Thank you for your post.

    Comment by Jacob Mack — 19 May 2010 @ 8:16 PM

  211. “A particularly nasty second order effect of warming that I do not wish on our Yankee friends. Frank Giger — 19 May 2010 @ 4:10 PM

    Assuming you are talking about the Kudzu [ku = earth, dzu (or tse, as is Lao Tse)= master; so, its chinese name means "master of the earth"] and not the toxic chemical human overrreaction, I think I would wish it on the willfully ignorant politicians obfuscating and delaying action to deal with global warming. Maybe if we planted some Roundup Ready(TM) kudzu to engulf the hallowed halls of Congress, it would get their attention?

    Comment by Brian Dodge — 19 May 2010 @ 9:46 PM

  212. > oxidation of CH4 to C02
    Remember, in sediment and water, oxidation is being done by methanogens — a biological process (the water is usually supersaturated). In air, I don’t know if organisms are pushing the reaction. But, enough, it happens.

    Comment by Hank Roberts — 19 May 2010 @ 9:54 PM

  213. 173 CFU: I don’t think that warmer necessarily implies that drought is worse. We know the atmosphere’s water vapor content is increasing as a result of rising temperature, and we expect, and I think observe that overall precipitation is increasing as well. So in order to be worse because of AGW a drought period must see an increase in precitation from warming that is less than the increase in evaporation due to the same cause. I don’t think that automatically follows. So droughts getting worse/more frequent, or high end precipitaion events getting worse are not obvious responses to rising global temperatures. In the precipitaion arena we need to demonstrate that the tails of the distribution are getting fatter -not just that the mean is shifting (to wetter). I know this is the expectation of many climate scientists, and that observations seem to indicate it is hapening, but some sort of understandable mechanism for why must exist.

    Comment by Thomas — 19 May 2010 @ 9:57 PM

  214. # 212… yes Hank,but it is not as significant. CH4 is not converting in large amounts to C02

    Comment by Jacob Mack — 19 May 2010 @ 10:38 PM

  215. … in the water.

    Comment by Jacob Mack — 19 May 2010 @ 10:39 PM

  216. Hank still of interest though:

    http://ocw.unu.edu/international-network-on-water-environment-and-health/unu-inweh-course-1-mangroves/Bacteria-and-

    fungi.pdfhttp://www.nature.com/ngeo/journal/v1/n7/abs/ngeo234.html

    http://www.nature.com/ngeo/journal/v1/n7/abs/ngeo242.html

    Not be ignored, but not so important in terms of ocean acidity. Just like meathane in the atmosphere is important, but less so than actual direct C02 with such different residence times.

    As always thank you for your thoughtful and referenced post.

    Comment by Jacob Mack — 19 May 2010 @ 10:53 PM

  217. Perhaps we can avoid vague generalities of droughts and storms, given the reasons to believe there will be *more* droughts in some places in, *more* precipitation in other places, and it matters which si which. For the USA, I hope everyone is familiar with the US Global Climate Research Program’s Global Climate Change Impacts in the United States, 2009, a book well-written and illustrated for a general audience, and freely available online.

    Particularly useful are the ~5-pages for each region of the USA, describing expectations for that region.

    Comment by John Mashey — 19 May 2010 @ 11:05 PM

  218. 188 Hank Roberts: THANK YOU! Now we know that what we have to deal with is paranoid personality disorder combined with coal company propaganda. That is a big advance. Now we have to look up how to deal with people who have paranoid personality disorder. That is a big step forward.

    You also told us that we must deal with the untrained mind in its own mindframe. That will be a big adjustment for some of us. We would rather train everybody to be scientists, which is not possible given the intelligence of the average person. [Nobody ever went broke by underestimating the intelligence of the average person.]

    Very well. We must deal with this information. RC must write unscientific but emotionally convincing articles from now on.

    Comment by Edward Greisch — 19 May 2010 @ 11:11 PM

  219. 188 Hank Roberts: An example of an article that works better but isn’t scientific:

    “Global Warming Has Already Happened. In the mid 19th century, the Mississippi river froze over in the winter so you could drive on it at St. Louis. That’s how St Louis became known as the gateway to the west. Now the Mississippi river is ice-free at Davenport, Iowa most years. Cattaraugus County New York [Olean, Little Valley] got 450 inches [37.5 feet] of snow per year in the 1950s and 1960s. Now it gets only 96 inches of snow per year. Hurricane season starts in spring now. Hurricane season used to start in the fall. Tornados used to happen in the summer. Now they happen all year. “

    Comment by Edward Greisch — 19 May 2010 @ 11:39 PM

  220. http://vmsstreamer1.fnal.gov/VMS_Site_03/Lectures/Colloquium/100512Norris/index.htm#

    This is the video for Dr. Norris’s colloquium presentation to Fermilab National Accelerator Laboratory, May 12, 2010.

    “Cloud feedbacks on climate: a challenging scientific problem”
Joel Norris, Scripps Institution of Oceanography

    Abstract: One reason it has been difficult to develop suitable social and economic policies to address global climate change is that projected global warming during the coming century has a large uncertainty range. The primary physical cause of this large uncertainty range is lack of understanding of the magnitude and even sign of cloud feedbacks on the climate system.

    If Earth’s cloudiness responded to global warming by reflecting more solar radiation back to space or allowing more terrestrial radiation to be emitted to space, this would mitigate the warming produced by increased anthropogenic greenhouse gases.

    Contrastingly, a cloud response that reduced solar reflection or terrestrial emission would exacerbate anthropogenic greenhouse warming.
    It is likely that a mixture of responses will occur depending on cloud type and meteorological regime, and at present, we do not know what the net effect will be.

    This presentation will explain why cloud feedbacks have been a challenging scientific problem from the perspective of theory, modeling, and observations. Recent research results on observed multidecadal cloud-atmosphere-ocean variability over the Pacific Ocean will also be shown, along with suggestions for future research.

    Comment by CRS — 20 May 2010 @ 12:30 AM

  221. > a drought period must see an increase in precitation from warming
    > that is less than the increase in evaporation due to the same cause

    No, because that would assume no change in the local patterns — which is the question this topic is all about discussing.

    More extreme local precipitation events could put the water in fewer places and more rapidly so more runs off and less goes into groundwater. I think that’s a pattern expected from the paleo records, though I’ll have to poke around and see if my memory is correct or someone has addressed it.

    Comment by Hank Roberts — 20 May 2010 @ 12:31 AM

  222. This is what I was recalling, among others:
    http://www.nature.com/ngeo/journal/v1/n8/full/ngeo262.html
    “… Here, we analyse a 99-year record of hourly precipitation observations from De Bilt, the Netherlands, and find that one-hour precipitation extremes increase twice as fast with rising temperatures as expected from the Clausius–Clapeyron relation when daily mean temperatures exceed 12 °C. In addition, simulations with a high-resolution regional climate model show that one-hour precipitation extremes increase at a rate close to 14% per degree of warming in large parts of Europe. Our results demonstrate that changes in short-duration precipitation extremes may well exceed expectations from the Clausius–Clapeyron relation. These short-duration extreme events can have significant impacts, such as local flooding, erosion and water damage.”

    And for paleo work,
    http://dx.doi.org/10.1016/j.palaeo.2006.09.011
    “… a significant but transient decrease in precipitation at the onset of the PETM but a gradual return to pre-PETM levels by the end of the interval. The paleosols also show additional, although less dramatic, wet/dry cycles within the PETM interval that may correspond to precessional cycles that have been identified in the marine record of the PETM. This study counters interpretations of increased precipitation for Wyoming at this time and shows the importance of detailed case studies of continental strata to test climatic generalizations and models that have been developed for PETM precipitation patterns.”

    Comment by Hank Roberts — 20 May 2010 @ 12:36 AM

  223. “213
    Thomas says:
    19 May 2010 at 9:57 PM

    173 CFU: I don’t think that warmer necessarily implies that drought is worse”

    I’m not saying that either, though that’s a LOT closer than some others are getting.

    Warmer means worse if nothing else changes.

    Therefore, to prove that AGW did NOT make that drought worse, you’d have to prove it didn’t make a difference IN THAT ONE SPECIFIC CASE.

    I.e. the one making the statement that the drought was NOT affected by AGW would have to show AGW did not cause any regional change or that the changes cancelled each other out.

    But the default is that it DID affect the drought.

    Comment by Completely Fed Up — 20 May 2010 @ 2:52 AM

  224. “With AGW and climate change in general there are regions that are usually hot and prone to droughts that will in fact become more moist due to localized weather and microclimate variations.”

    And this case is where there ARE generally hot and prone to droughts.

    Funny how nobody is noticing this and LEAPING to the conclusion I’m talking about all and every place and case.

    Isn’t it.

    “We cannot just assume that there is or there will be worse droughts everywhere it is hot and dry to begin with due to changes in climate”

    Yeah. Good job I’m not, isn’t it.

    Doesn’t stop people slamming a statement I’VE NEVER MADE.

    Comment by Completely Fed Up — 20 May 2010 @ 2:54 AM

  225. “207
    Frank Giger says:
    19 May 2010 at 8:02 PM

    CFU, go to post 93 for the study showing the drought was both within historical norms and had no markings of global warming forcing.”

    And says NOT ONE THING about whether it would be less severe if AGW didn’t happen.

    [edit]

    Comment by Completely Fed Up — 20 May 2010 @ 2:56 AM

  226. “02
    Septic Matthew says:
    19 May 2010 at 4:52 PM

    200, FCU: So, Septic, what do YOU say is causing the warming?

    I don’t know. I am not sure that the “warming” is ongoing or paused, and I expect that, because I am 63, I may never know.”

    Septicemia, the warming hasn’t paused.

    That you arent sure whether it has or not shows rather clearly how you are not willing to consider anything other than evidence that AGW isn’t happening and YOU are the one who is not open to ideas.

    You’ll never know not because you’re 63, but because you DO NOT WISH IT TO BE.

    Comment by Completely Fed Up — 20 May 2010 @ 2:59 AM

  227. CFU, I won’t play your word games. Anyone who has followed the thread will know how the drought discussion started, will know who has argued what based on cited sources, and will know to evaluate your representations of other people’s positions accordingly. If there’s nothing more of substance to discuss, we’re done.

    Comment by CM — 20 May 2010 @ 3:26 AM

  228. Dear Moderators

    A very very small number of regular posters reduce reading this forum to a painful experience as they try to belittle everyone with an alternative view in an attempt to show how smart they believe themselves to be. This greatly reduces the effectiveness of what I would believe to be the public outreach function of the blog. Why do you allow them to impact so negatively on your blog?

    Kind Regards

    Michael

    Comment by Michael — 20 May 2010 @ 3:32 AM

  229. Naindj 165: To link all this to human activities (the “A” in AGW) you need far more and this is why there are all these debates (Hockey Stick and MWP, cliamte sensitivity and feedbacks, etc…)

    BPL: There is no “debate” on this particular issue except among the ignorant. That CO2 is rising and that it’s of human technological origin was pretty well established in the 1950s.

    Comment by Barton Paul Levenson — 20 May 2010 @ 4:41 AM

  230. The AGW/drought connection can’t be figured out from assuming one vertical column. It’s an effect of the fact that under AGW, precipitation moves away from continental interiors and toward the coasts. Without the horizontal distribution, you can’t see it.

    Comment by Barton Paul Levenson — 20 May 2010 @ 4:52 AM

  231. There was a recent study in Oz about pan evaporation rates in Oz suprisingly not having increased in spite of the extra heat. It may have been due to more higher humidity air coming down from the north,. Sorry not to have the reference

    Comment by Robert D — 20 May 2010 @ 5:38 AM

  232. OT, Apologies. Latest Arctic sea-ice extent has just about hit the 2007 minimum for this month: http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png

    Grim.

    Comment by Steve Brown — 20 May 2010 @ 6:09 AM

  233. “You guys do realize that even with a quantum computer we could not really predict many aspects of climate over the next 10-30 years.”

    The problem with quantum computers is working out how to program them. You need to set up your quantum states so that their energetic solution is the solution to the question “what is the climate doing”.

    This isn’t going to require one qbit per atom in the atmosphere, but it’s still a lot of qbits needed, and decoherence cannot happen until you’ve set the entire thing up.

    Just as with current machine state computers, there are some classes of problem that quantum computing cannot answer. The land of Panacea sank into the ocean of practicality a long time ago…

    Comment by Completely Fed Up — 20 May 2010 @ 7:08 AM

  234. OK guys, I’m struggling to understand some of the statements in Seager et al. 2009. Most confusing to me is this passage from the conclusions. The authors are comparing the robust linking of Southwestern drought to AGW, and refer to P (precipitation) and E (evaporation):

    “To the extent that P − E is reduced [in the Southeastern drought], the mechanism is different from that for the robust projection of reduced P − E in the Southwest which is driven by reduced P, with E reducing as soil moisture drops (Seager et al., 2007b). In the post 2005 drought, according to the NCEP Reanalysis, E dropped along with P, indicating that the recent drought was driven by a reduction of P and not by an increase of E.”

    OK, so E drops “along with” (presumably meaning “concurrently with”) P in the Southeastern case, while lagging in the Southwestern. But in both cases, this passage clearly says, the drought is driven by decreases in P. This is “different?” (It’s also bathetically obvious, if you lived through the drought–there was no question about the reality of “reduced P!”)

    Is there an editorial/auctorial lapse in clarity here, or am I just missing something?

    And if the characteristic difference was the time lag of decreases in E–and I can testify from personal experience just how dry the soil became in the “post 2005″ Southeastern drought, soil texture in my back yard was reminiscent of wood ash–then what does this difference imply?

    Seager et al 2009 is very clear that the drought looks much like past (ie., pre-AGW) droughts and that from that perspective, there is no reason to suspect AGW as a cause. I don’t see any way to argue that, short of detailed re-examination of the data. Absent that, it’s “just a fact.”

    On the other hand, given the paper’s conclusion that the models do not reproduce the regional details robustly, it seems questionable to me how well-defined the profile of AGW’s influence on Southeastern drought in general actually is at present.

    Comment by Kevin McKinney — 20 May 2010 @ 7:15 AM

  235. Correction: “argue that” really should have been “argue *with* that.” (Penultimate paragraph.)

    Comment by Kevin McKinney — 20 May 2010 @ 7:19 AM

  236. “On the other hand, given the paper’s conclusion that the models do not reproduce the regional details robustly, it seems questionable to me how well-defined the profile of AGW’s influence on Southeastern drought in general actually is at present.”

    OK, how does the model’s inability to calculate exactly how much AGW did or did not affect the drought affect the scientific fact that warmer weather makes a drought worse?

    We can’t model the properties of exotic metallic alloys. This doesn’t stop them from being made, because we know tantalum has an effect on mild-carbon steel, we just can’t model how exactly it does this.

    Comment by Completely Fed Up — 20 May 2010 @ 7:39 AM

  237. “perspective, there is no reason to suspect AGW as a cause.”

    [edit]

    I’m not saying AGW was a cause.

    Comment by Completely Fed Up — 20 May 2010 @ 7:41 AM

  238. “226
    CM says:
    20 May 2010 at 3:26 AM

    CFU, I won’t play your word games.”

    Uh, what “word games”?

    You complain that it cannot be said that AGW caused that drought.

    This is YOUR word game.

    I never said it.

    Comment by Completely Fed Up — 20 May 2010 @ 7:43 AM

  239. OK, peeps. A poll.

    Indicate which ones you agree with by listing as

    YES: # # #

    and which you disagree with by listing as

    NO: # # #

    1) AGW (climate change) creates warmer weather.

    2) Warmer weather makes drought more severe.

    3) Droughts are made more severe if you increase temperatures.

    Which ones are agreed as correct and which ones as wrong?

    Comment by Completely Fed Up — 20 May 2010 @ 7:47 AM

  240. “Not every weather event – even ones that make a very statistically noisy 18 month long one – is tied to Global Warming.”

    EVERY weather event is tied to global warming (climate change).

    Weather that increases precipitation by 2mm/hr affects a climate that is dry more than it affects a climate that is inundated.

    If you change the climate, the events you see are changed.

    If this were not so, you would be unable to see climates change.

    Comment by Completely Fed Up — 20 May 2010 @ 7:50 AM

  241. Further to 240, the issue may be clarified by noting that Frank has the process the wrong way around.

    Every event is affected by the climate.

    But no one event lets you tell how much the climate changed.

    Frank has it that weather drives climate. It’s the other way round. Weather is the expression of climate.

    A hand of cards is not defining pok er. But pok er DOES define what you get in a hand of cards.

    Hand == Weather.
    Pok er == Climate.

    Comment by Completely Fed Up — 20 May 2010 @ 8:28 AM

  242. I don’t know. I am not sure that the “warming” is ongoing or paused

    Paused? For each successive month for the last several months, it has been the warmest 12 months on record. Paused/stopped wasn’t a good point to begin with, and now, even by its own criterion, is defunct.

    Comment by Jeffrey Davis — 20 May 2010 @ 8:43 AM

  243. Can I say that it’s strange to talk about the “cause” of something as non-discrete as weather? Where does “weather” happen? When does it begin and end? Does it end where it begins or does it move somewhere else? And if it moves somewhere else does it have a different cause there than where it began? Etc.

    As someone else has noted, the Earth is just getting warmer, and we’re getting the kind of weather that you get with a warmer Earth.

    Comment by Jeffrey Davis — 20 May 2010 @ 8:48 AM

  244. Hank, 222,223 BPL 230, thanks for trying to provide an explanation for the (to me) unintuitive fattening of the tails problem. I am convinced the data shows it is a real effect. My problem is I lack a mechanism which I could plausably argue with a sceptic that provides this predicition with some degree of credibility. Perhaps no simple handwaving argument exists, and you can only ascertain it from a detailed simulation, or from observing natures solution to the changes in the system. But the problem of convincing the skeptic would then remain unsolved. I for one have high confidence in the global results of climate simulations (it will get warmer), but don’t find the low level details (location X will respond like XXX) to be have usable confidence. Now I can think of a few weak arguments, but I don’t think they are up to the challenge:

    (1) With warmer temps for a given ratio of P/E (which by Claudius-Clapteron we might expect to remain constant), drying will ocurr on a faster timescale. So for a fixed duration drought of a fixed intensity (change in the log(P/E)) the drying can progress further.

    (2) Changes in general circulation. If we can show that the tendency of planetary waves to intensify and/or get stuck in a pattern increases with global temperature then we have an explanation for the fat tails problem. This might be due to how close the natural wavelength is to a resonence (an integer times the wavelength equals 2 time pi, i.e. teleconnections tend to reinforce regional signals). But, a priori one wouldn’t expect that this is more than 50% likely.

    Comment by Thomas — 20 May 2010 @ 8:49 AM

  245. Kevin McKinney #234 – as clear as mud. As you point out, reads as self-contradictory.

    Comment by Dappledwater — 20 May 2010 @ 8:53 AM

  246. “So for a fixed duration drought of a fixed intensity (change in the log(P/E)) the drying can progress further.”

    It can also make the reversion to wet clime harder: if the ground is too hard baked, the rainfall will skoosh right out to sea, causing a flood on the way, whereas if there were a little moisture to keep the pores in the ground open, more would have seeped in and

    a) not added to the flood
    b) would be available next time the day didn’t rain

    Comment by Completely Fed Up — 20 May 2010 @ 9:03 AM

  247. “Can I say that it’s strange to talk about the “cause” of something as non-discrete as weather?”

    Certainly.

    However, can I say it’s strange to talk about talking about the cause of something when nobody has talked about the cause of something?

    Comment by Completely Fed Up — 20 May 2010 @ 9:04 AM

  248. CFU (#236), I’m not arguing–I’m asking. Statements are there to help those who may be able–and inclined–to help me, to diagnose my confusion better!

    That said, you seem to be talking past me. Yes, a drought in warmer weather will be worse than one in cooler weather, all other factors being equal. And yes, by extension, AGW should worsen drought via what Seager et al. call “increased E.” In that, you and Seager et al (and me, for that matter) all seem to be agreeing, if I have this right. (That implies a “yes” to your three propositions in #239, by the way.)

    But what Seager et al. are saying is that, according to the best data that they have, the Southeastern drought did not differ from historical droughts. That’s not a theory, that’s what they found when they looked at the data. It wasn’t drier, it wasn’t longer. And that’s what I find hard to argue with–unless one is prepared to do a thorough analysis of the same and/or related data. And I’m not equipped to do so.

    (BTW, that’s not contradicting AGW theory–for one thing, IIRC, regional warming in the Southeast for the decades around the turn of the 20th century was such that we haven’t yet exceeded the anomalies recorded then. IOW, AGW hasn’t–yet!– driven temps in this region past historical norms, so why would we expect droughts to show a different profile? That doesn’t negate the reasonable expectation that those norms WILL be exceeded, and quite likely not so far in the future, either.)

    What you don’t seem to get about Seager et al. is that they are, in part, doing attribution. They are doing that largely by comparing what the models come up with when driven by historical SSTs to what the instrumental record says. What they found was that: 1) results were not very robust across model runs; and 2) there was only a weak correlation between the two, and that for the winter half of the year only. Hence, the drought “lacks an AGW profile”–or however they phrased it.

    My reading of this would be rather that we may not have a very good idea yet of what that AGW profile specifically for drought in the US Southeast may actually be–and I would have thought that that was somewhat in support of your general points about how AGW may have affected the drought, since otherwise one would probably be led to accept the Seager et al conclusion quoted at face value.

    I’ve responded at some length, CFU, but I truly am not trying to argue any position. I’m not “challenging” Seager et al., nor relying upon it as an “authority” to support some “point.”

    I am interested in trying to grasp what they are saying about an event that was very vivid for me, and consequently to understand what that event really has to say about the greatest crisis of our day–AGW. (For one thing, my personal domestic water supply is currently at risk due to the legal repercussions of that drought!–along with that of the rest of the population of the county I live in, of course. It’s out of the news right now because reservoirs are full, but the political system remains dysfunctional in dealing with a clear and present danger to the health and wealth of this area.)

    That’s why I asked about that bit from the conclusion that I found confusing. (Any ideas, anyone?)

    Comment by Kevin McKinney — 20 May 2010 @ 9:18 AM

  249. Kevin McKinney wrote: “… we may not have a very good idea yet of what that AGW profile specifically for drought in the US Southeast may actually be …”

    Have you perused the chapter on the Southeast in the US Global Climate Research Program’s Global Climate Change Impacts in the United States, 2009, which John Mashey referenced in comment 217?

    Comment by SecularAnimist — 20 May 2010 @ 10:01 AM

  250. Thomas, 244, you’re restating the original post — that’s the point of the thread here, that it’s the regional details of the past millenium we need, in order to have a better idea what we can learn from that past period.

    As to “the data shows it is a real effect…. I lack a mechanism … that provides this predicition with some degree of credibility.” — It’s been observed; it’s happening. As my old doctor used to say, “In theory, theory and reality are the same, but in reality, they often differ.”

    Comment by Hank Roberts — 20 May 2010 @ 11:01 AM

  251. SA, thanks, that’s a good reference. Hadn’t seen it, though I have seen many of the same conclusions elsewhere.

    It’s not what I was referring to in my comment re the Seager et al paper, which is what you quote. By “AGW profile specifically for drought in the US Southeast” I was trying to convey factors such as the “P & E” profiles, as well as larger issues such as the linkage (or lack thereof) to ENSO which the Seager paper addressed.

    What Seager et al seems to say in this regard is that model work can reproduce Southwestern drought patterns much more robustly than Southeastern ones. The actual sentence from Seager et al. that led to my perhaps clumsy inference was this:

    “As such model simulations forced by historical SSTs have very limited skill in reproducing the instrumental record of South precipitation variability and actual predictive skill will also presumably be low.”

    (It’s from the abstract, and got ‘quoted around’ in previous posts.)

    Since I’m quoting from the paper, the last sentence of the Conclusion is worth putting out there as well:

    “. . .the projection of a modest reduction in the current century of P − E by the model ensemble indicates
    that climate change should not be counted on to solve the Southeast’s water woes and is, in fact, as likely to make matters worse as better.” Which is essentially CFU’s point–warming will increase evaporation.

    Comment by Kevin McKinney — 20 May 2010 @ 11:06 AM

  252. Thanks, Dappledwater (#245)–at least I know it’s not just me!

    (Lovely screen-name, BTW, and very apposite for the subthread besides.)

    Comment by Kevin McKinney — 20 May 2010 @ 11:16 AM

  253. re: #249
    Yes, people may argue with what USGCRP writes, but it makes no sense for people to write vague generalities when there is current, high-quality, concise, well-written information easily available.

    Recall the original post was about the need to better understand *regional* effects, as those strongly affect local/regional decisions and investments, especially for long-lived infrastructure.

    Comment by John Mashey — 20 May 2010 @ 11:46 AM

  254. Barton Paul Levenson, 229
    “BPL: There is no “debate” on this particular issue except among the ignorant. That CO2 is rising and that it’s of human technological origin was pretty well established in the 1950s.”

    I got the impression this blog is populated by sophists…
    It is getting warmer. Fine
    CO2 is rising. Fine
    This CO2 is mainly from human activities. Fine
    But to say that it is getting warmer because of human produced CO2, there is a huge missing step.

    [edit -- give us a break, the issue of attribution has been the focus of two decades of research, has been gone over many times on this site. The attribution of the warming of recent decades to human impacts can very likely be made, is the conclusion of the IPCC, all of the major national academies, etc. If you've got something new and interesting to say here, fine. But no trolling on old ground, ok?]

    Comment by Naindj — 20 May 2010 @ 12:17 PM

  255. “That said, you seem to be talking past me.”

    That’s because, Kevin, your post had a section dealing with whether you can or cannot ascribe a weather event’s genesis as a climate event. To answer that required I talk past you who were (rightly) saying this to those who are contending that was what I’d said.

    It’s a little cumbersome because that content wasn’t directed at me, hence my wording was cumbersome.

    “Msomewhat in support of your general points about how AGW may have affected the drought”

    Aye, I have only maintained that it had an effect and that, absent any detailing to the contrary, that the event was made worse.

    “I’ve responded at some length, CFU, but I truly am not trying to argue any position.”

    And all I’ve tried, Kevin, is to argue my position wasn’t that the drought event was caused by AGW, merely made worse by it.

    But it seemed to continually being missed or argued against.

    I was arguing for point/counterpoint for the statements made, not ones that hadn’t.

    “But what Seager et al. are saying is that, according to the best data that they have, the Southeastern drought did not differ from historical droughts. That’s not a theory, that’s what they found when they looked at the data.”

    I would maintain that this is no proof that the changed climate didn’t make it worse.

    Earth II may have had a less severe than normal drought that this earth, with the climate change, had a normally severe drought for the area.

    This still constitutes AGW having made it worse (a light drought made a normal drought) and still doesn’t make the drought an exceptional event.

    “It wasn’t drier, it wasn’t longer. And that’s what I find hard to argue with–unless one is prepared to do a thorough analysis of the same and/or related data.”

    Whether the drought was drier or longer doesn’t change whether AGW had a worsening effect. It only means that this event wasn’t driven outside the normal range of events by it.

    It’s the drought version of the 1999 “cooling”: it was climatically warmer, but the variations of other factors added to that warmer trend resulted in an event that was cooler.

    Same here.

    Comment by Completely Fed Up — 20 May 2010 @ 12:23 PM

  256. Sure glad the Arctic ice is recovering (according to the denialist side)

    http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png


    A Climate Minute The Greenhouse EffectHistory of Climate ScienceArctic Ice Melt

    ‘Fee & Dividend’ Our best chance for a better future – climatelobby.com
    Learn the Issue & Sign the Petition

    Comment by John P. Reisman (OSS Foundation) — 20 May 2010 @ 12:26 PM

  257. However, can I say it’s strange to talk about talking about the cause of something when nobody has talked about the cause of something?

    Sure. Are you talking about this thread?

    Strange.

    Comment by Jeffrey Davis — 20 May 2010 @ 12:43 PM

  258. CFU: I was making a general statement with support from the IPCC report and elsewhere in peer reviewed research in addition. I do not doubt there will be hot and dry regions affected gravely by warming. However, some crops adapt well to droughts and others to dryer conditions just fine. Some absorb more C02 and grow quite well too. Of course the increased growth from C02 can deplete the soil of nitrates and in some areas pests will become more plentiful and large in body mass. I am not accusing you of saying anything you have not, however, you focus so heavily on the aspects of droughts, it seems to me and few a others here, that you forget that AGW is not a complete detriment to crop yields and it is a tough thing to measure, or attribute GHG forcing to droughts becoming higher in magnitude or more frequent. That the mean global temperature is warming is indisputable and that GHG’s are VERY LIKELY (>95%) to be contributing to the warming of the globe is true based upon sound analysis. That some drought prone areas will become worse makes perfect sense and has data to support such assertions. I do think there are other areas to focus on which are easier to study and measure.

    CFU you are a very sincere person, but you seem at times to get very easily offended and hyper. I was a bit like that when I first came to RC a few years ago myself. This is not about you though, this is about the issues we face in a warming world and GHG emissions roles in that.

    Comment by Jacob Mack — 20 May 2010 @ 1:11 PM

  259. http://www.scidev.net/en/news/rising-co2-levels-could-reduce-protein-in-crops.html (warming reduces crops’ nitrogen use, add more fertilizer)

    http://oceanservice.noaa.gov/products/pubs_hypox.html (excess nitrogen runoff from overfertilization causing dead zones in fisheries)

    ” … she swallowed the spider to catch the fly ….”

    Comment by Hank Roberts — 20 May 2010 @ 1:24 PM

  260. Hank Roberts # 222: Thanks for the references and the discussion. I will add, though, that yes, they can lead to floods and erosion and the future may in fact hold such consequences for us, but nothing as of yet has occurred outside of historical happenings prior to the industrial revolution. We do have time to lower GHG’s, but I fear the next generation may have more consequences to face than people from our respective generations. That said, these predictions still need a lot of error analysis and more data collection to fine tune them. We should look at the current consequences we are seeing now (which are plentiful enough) in warming, dimming, and overall consequences of pollution in general and find reason there enough to make positive changes in energy production and lowering resulting emissions. We can never give up all fossil fuels, but we can certainly lower their use to what is most appropriate with some adoption of carbon capture, I think. Looking at the potential for a few floods and worse droughts, is not going to put the fire under law maker’s and corporate CEO’s butts as expected anyways. Human beings like to suffer dire consequences first before they take action. This is true in transportation, factory conditions and the materials used in home building and plastic making…

    Again there is time and the attribution of any current severe sediment loss and flooding relating to AGW is not strong as of yet, but other factors are like: aquatic life dying and becoming extinct, less forests to absorb the high C02 levels etc…

    Comment by Jacob Mack — 20 May 2010 @ 1:26 PM

  261. Kevin, I agree that paragraph looks strange. Read with the preceding paragraph, I parsed it as follows:

    1. Most of the models project that, in the Southeast, there will be a net drying (negative P – E) because, though precipitation will increase, evaporation will increase more. The projections are not very robust (a third of models say otherwise).

    2. The models also project, more robustly, a net drying of the Southwest, but through a different mechanism: evaporation will actually decrease, precipitation will decrease more.

    So the contrast, if I read it correctly, is between the different mechanisms leading to drying in the projections for the two regions in general. The contrast is not between the SW projections and the specific SE drought event. If so, moving that sentence up before the paragraph break would have made the meaning clearer.

    3. Turning to the recent Southeast drought, observations seem to show that it was driven by decreased precipitation, not increased evaporation [which would contrast with the projected pattern for the Southeast, and I assume that's the point they're making].

    I may well be wrong, but that reading seems to make sense of it.

    Comment by CM — 20 May 2010 @ 1:27 PM

  262. Jacob, you’re right.

    But I’m at a loss as to why you think you need to tell me this.

    “however, you focus so heavily on the aspects of droughts,”

    Yah. Did you read why? I put it out there several times. Here it is AGAIN.

    http://www.realclimate.org/index.php/archives/2010/05/what-we-can-learn-from-studying-the-last-millennium-or-so/comment-page-3/#comment-174921

    Now when you’re talking about droughts, talking about droughts is right, isn’t it?

    “CFU you are a very sincere person, but you seem at times to get very easily offended and hyper.”

    Well because I get people telling me that I’m wrong because you can’t say the drought was caused by AGW.

    I never said that.

    Isn’t it right to get pissed off when that happens?

    And now I’m getting told off for concentrating on droughts in a question ABOUT DROUGHT.

    If I were hyper I’d be a damn sight more vociferous, with damn good reason too.

    Comment by Completely Fed Up — 20 May 2010 @ 1:31 PM

  263. “However, can I say it’s strange to talk about talking about the cause of something when nobody has talked about the cause of something?

    Sure. Are you talking about this thread?”

    Could you show me where someone has stated that AGW *caused* the SEUS drought?

    If not, are you talking about THIS thread?

    Comment by Completely Fed Up — 20 May 2010 @ 1:32 PM

  264. PS Jeffrey, to be clear: YES, I AM talking about this thread.

    Which one are you reading?

    Comment by Completely Fed Up — 20 May 2010 @ 1:34 PM

  265. http://www.ametsoc.org/policy/drought2.html“Drought differs from other natural hazards in several ways. First, it is a “creeping phenomenon,” making its onset and end difficult to determine. The effects of drought accumulate slowly over a considerable period of time and may linger for years after the termination of the event. Second, the absence of a precise and universally accepted definition of drought adds to the confusion about whether or not a drought exists and, if it does, its severity.”
    “Drought is a normal, recurring feature of climate; it occurs in virtually all climatic regimes. It is a temporary aberration, in contrast to aridity, which is a permanent feature of regional climate. Drought should be considered relative to some long-term average condition of balance between precipitation and evapotranspiration (ET) in a particular area, a condition often perceived as “normal.” Common to all types of drought is the fact that they originate from a deficiency of precipitation that results in water shortage for some activity or for some group. It is also commonly recognized that other meteorological elements, such as temperature, wind, and relative humidity, may aggravate the severity and impacts of drought in some instances.”

    http://www.ncdc.noaa.gov/oa/climate/research/prelim/drought/palmer.html
    “While Palmer’s indices are water balance indices that consider water supply (precipitation), demand (evapotranspiration) and loss (runoff), the Standardized Precipitation Index (SPI) is a probability index that considers only precipitation. ”

    If your definition of “drought” is based on the Palmer indices, since they estimate evapotranspiration which is temperature dependent, then a PDSI of -5 at an average temperature of 15 deg C is no more or less severe than a PDSI drought of -5 at 16 deg C, since the increase in evapotranspiration at the higher temperature will have been compensated by an increase in precipitation or decrease in runoff to arrive at the same PDSI value.
    If you define “drought” by the SPI, then the impacts of equal index drought will be more severe at higher temperatures, since the increased evapotranspiration will increase plant moisture stress, reservoir drawdown, and “water shortage for some activity or for some group,” given the same amount of precipitation.

    http://www.atmos.washington.edu/~dargan/summaries/flc07.html
    “One of the most consistent responses of climate models to global warming is a widening of the Hadley circulation. Since the downward branch of the Hadley cell is associated with many of the largest deserts on Earth, the poleward expansion of the Hadley cell also means a poleward expansion of the dry zones. In climate models, the poleward expansion of the Hadley cell is closely linked with the predicted drought in the Southwest US, the Mediterranean, and other locations in similar latitude bands.”
    But not the Southeastern US. Florida is a swamp, at the same latitude as the Chihuahua Desert in Mexico. North Carolina temperate forests get 1+ meter of rain per year; Northern Arizona at the same latitude gets ~ 1/3 meter per year. The presence of the warm Gulf and the Gulf Stream on 2 sides of the Southeast provides ready moisture when the winds are from the southwest around to easterly; southerly winds at the leading edge of low pressure areas which produce uplift and precipitation bring copious moisture into the southeast, but dry air from the mexican deserts into Arizona. The drying cause by expansion of the Hadley cell dry zone into Florida, Georgia, and the Gulf Coast will be ameliorated by proximity to the warm water source for moisture. As Seager et al point out “The Southeast clearly lies at the poleward fringe of the region of projected subtropical drying,” so short term variability(turbulence in the position of the edge) will often lead to favorable weather patterns bringing moisture ashore.

    Seager et al say “In the post 2005 drought, according to the NCEP Reanalysis, E dropped along with P, indicating that the recent drought was driven by a reduction of P and not by an increase of E.” implicitly using Palmer definition of drought. Don’t tell the denialists, but if one accepts the AMS technical differentiation between drought and aridity, AGW will in many cases increase aridity, which indirectly increases drought.

    Seager et al also find “… precipitation minus evaporation (P – E) decreases modestly in the annual mean, driven by increasingly negative P -E in summer.” Right now, the Jordan reservoir in central NC is 2 feet above control level, and consequently releasing ~30000 cubic feet per second of water into the Cape Fear River; that water will not be recoverable if it gets dry this summer. Summer decreases in water can’t be compensated by capture of winter precipitation in our current reservoirs to reflect a modest decrease in annual average – “that results in water shortage for some activity or for some group.” Development demand has been permitted in central NC based on reservoir delivery available with lower seasonal variation in precipitation than we will see with AGW. Raleigh has instituted year round water conservation rules: they will undoubtedly become more strict and more expensive as the effects of AGW unfold.

    Comment by Brian Dodge — 20 May 2010 @ 1:39 PM

  266. “but nothing as of yet has occurred outside of historical happenings prior to the industrial revolution.”

    Here’s a thought experiment.

    The effect of a process is randomly distributed in strength around a value 1.0. It is a poisson distribution, so goes all the way to infinity.

    Chance of an event being less than 1.0 strength: 50%.

    Now increase the severity of ALL events (add an active ingredient, warm it up, whatever) by 4%.

    Chance that an event is less than 1.0 strength: very slightly less than 50%.

    So you can’t say “no effect” just because you’re seeing one event less strong than the average.

    A history spanning 200 years will show 2 one-in-a-hundred-years events in the past. If they are now once-a-decade, in the next 10 years you’ve seen a third event that is no stronger than ones you’ve seen before TWICE.

    So you can’t say “no effect” just because you’re seeing an event that has been seen before.

    Your position is wrong in so many ways, it’s not even good enough to be merely wrong.

    Comment by Completely Fed Up — 20 May 2010 @ 1:40 PM

  267. 226, CFU: You’ll never know not because you’re 63, but because you DO NOT WISH IT TO BE.

    That is something that you can not possibly know.

    What’s more curious about your inference is that proponents of the AGW theory have claimed that they wish it were not true, so that even known wishes have ambiguous evidentiary value.

    Comment by Septic Matthew — 20 May 2010 @ 1:58 PM

  268. RC, any plans on doing a post regarding Lyman et al and their newly published* integration/assemblage/synthesis of various ocean heat content studies?

    In particular it would be interesting to hear any rumors concerning plans to follow ocean heat a bit deeper. I see that Gregory Johnson has published several papers on deeper heat content showing small but statistically significant warming so there’s at least some activity in that department.

    Wouldn’t it be great if some ARGO-like buoys capable of deeper operation were launched? Even a few hundred might be a help w/regard to temperature and of course it would also be fascinating to track where they popped up.

    * Robust warming of the global upper ocean
    John M. Lyman, Simon A. Good, Viktor V. Gouretski, Masayoshi Ishii, Gregory C. Johnson, Matthew D. Palmer, Doug M. Smith, Josh K. Willis
    Nature 465, 334-337

    Comment by Doug Bostrom — 20 May 2010 @ 2:12 PM

  269. “That is something that you can not possibly know.”

    “Ye shall know them by their fruits” (Matt 7:16 )

    Comment by Completely Fed Up — 20 May 2010 @ 2:39 PM

  270. Arrgh – should have been “other meteorological elements, such as temperature, wind, and relative humidity,”

    Comment by Brian Dodge — 20 May 2010 @ 3:11 PM

  271. # 266 Now, we do not have any bridge in our communication.

    Comment by Jacob Mack — 20 May 2010 @ 3:15 PM

  272. CFU I did, however, enjoy your thoughtful post response on the quantum computer.

    Comment by Jacob Mack — 20 May 2010 @ 3:17 PM

  273. On statistics, droughts and floods:

    Speaking as an old farm boy, and hence about things kids learn before they’re 10:

    1) Average rainfall matters.
    2) But variability often matters a *lot* more, in 2 ways:
    the mean might stay constant, but increasing variability tends to cause:
    a) Droughts get longer or worse, sometimes, and one long enough/bad enough is The End.
    b) At the other extreme, extra precipitation is only useful to the extent that you don’t get flooded, and up to the point where the reservoir capacity is exhausted. AS I recall, one of the problems in the SouthEast is the lack of adequate reservoir capacity, hence states fighting over water rights, something long familiar to the US West.

    Comment by John Mashey — 20 May 2010 @ 3:32 PM

  274. # 273 John Mashey, well said again.

    Comment by Jacob Mack — 20 May 2010 @ 3:55 PM

  275. CMS, Brian, thanks for your thoughtful responses. CMS, your reading does make sense–though when I think of how dry the soil became during the drought, it’s hard for me to imagine how E possibly could have increased after the first year or so–there was so little moisture left there to evaporate. (Yeah, I know, if that were quantified I might see it differently.)

    Brian, some good info to chew on.

    John Mashey, well said indeed–though it feels a bit odd to me to describe Lake Lanier as “inadequate,” I suppose it is indeed a logical description relative to the need for water downstream.

    Comment by Kevin McKinney — 20 May 2010 @ 4:32 PM

  276. Septic Matthew, allow me to translate CFU’s snark: I believe he means that you do not wish to know–and correspondingly that if you did wish to know, you could reach the same level of confidence (e.g. 90-95%) that countless scientists have reached before you.

    Comment by Ray Ladbury — 20 May 2010 @ 4:37 PM

  277. “enjoy your thoughtful post response on the quantum computer.”

    It’s not all that deep: I know how to set up two qbits but that’s as far as what I could follow took me.

    Rather the same with normal computers, though: try reading how to write a ULA or a floating point converter using only NAND gates.

    Makes your head hurt…

    Mind you, I guess they use hardware descriptive languages to build them now, rather than go through the building blocks.

    Comment by Completely Fed Up — 20 May 2010 @ 4:39 PM

  278. re 271: the point is that your position I quoted in 266 is a valueless statement. Either trivially true, in which case, adds nothing, or very wrong indeed in that you wish to draw a conclusion from it (because it IS valueless).

    Yes, that event wasn’t outside the normal range.

    But then a normal range includes one-in-ten-thousand-year events.

    Heck, a once-in-a-decade event turns up and you have no proof of the *magnitude* of the effect until you’ve had several in a decade. However, each event is STILL only a one-in-a-decade event.

    A hurricane that is force 3 is still fairly mild, but if it had been 2C cooler on the ocean, it would have been a force 2.

    Did not the temperature of the ocean make it worse? Even though a force 3 hurricane is not unusual?

    Yes. Yes it did.

    Comment by Completely Fed Up — 20 May 2010 @ 4:46 PM

  279. I’ll have several comments on “The timing of Pleistocene glaciations from a simple multiple-state climate model” by Didier Paillard
    http://www.nature.com/nature/journal/v391/n6665/full/391378a0.html
    for which one mght want the pdf for the differential equation in question. After explaining what’s going on throughout the entire
    http://en.wikipedia.org/wiki/Quaternary
    I’ll attempt to relate this elegantly simple model to the climate of the last two millennia. But first we want to have some understanding of the last half of
    http://www.globalwarmingart.com/wiki/File:Five_Myr_Climate_Change_Rev_png
    and we’ll start with the last 1.1 million years with the climate cycling from
    mode 0: interglacial
    mode 1: interstadial (mild glacial)
    mode 2: stadial (full glacial)
    and back to mode 0. These three modes are supposed to be due to the three states of MOC, which is at least plausible.

    The state variable is v = v(t) to represent something similar to ice volume, but as we can only view the d18O proxy (as linked above), v(t) actually means something more like 60% ice vloume, 40% deep ocean temperature (see Willy Broecker,’s “The Great Ocean Conveyor”). Anyway the differential equation in the absense of forcing is

    dv/dt = z(m) – v

    where z(m) is the stable value of v(t) depending upon mode m. If perturbed away from z(m), v(t) relaxes back to that value along a decaying exponential. Incidently, I’ve chosen a time unit so that the characteristic time of the relaxation is unity, tens of kiloyears for this model.

    Now we add the radiative, orbital forcing F = F(t) in the far north:

    dv/dt = z(m) – v – F

    so that the equation is relaxing to the (always changing) (z(m)-F(t)). But more, once a threshold is reached the modes switches to the new mode
    (m+1) mod 3.
    [Each of the three modes have possibly different characteristic relaxation times, a detail I ignore for simplicity.]

    Rather amazingly, at least to me, Didier Paillard is able to give a decent account of of the last 1.1 million years of a benthic d18O record. The results are insenstive to wide variations in mode switch values of v, characteristic times and somewhat insensitive to the choice of orbital forcing reconstruction [a difficult astronomical calculation]. I’ve studied two other, newer attempts to reproduce the “ice age” cycling. This one is the simplest and clearest, involving but one ODE with the only nonlinearity being the mode switching.

    Comment by David B. Benson — 20 May 2010 @ 5:32 PM

  280. # 277: Yeah, I recently took a few computer information systems and basic programming courses. The quantum internet is around, but the computer is not quite there yet. I am by no means an expert in that area, but it is a fascinating area just the same.

    # 278: No, not always, and not in the context of regional climate changes. Droughts worsened by warming probably will happen and in the near future we should be able to resolve some issues in way of attribuion and prediction, but we cannot do that yet AND warming actually helps some areas with crops AND some areas which cool due to local wind and temperature shifts also benefit. This is based upon peer review and recent reporting in several scientific magazines as well. C02 can temporarily aid plant growth and then inhibit nitrate uptake as the article Hank referenced also, but not all plants have the same issues with this. We do need to add more nitrates to soil that needs it and use more gentically modified crops that can adapt to changes that are detrimental to crop yields. That is also stated in the science and Bio-engineering. Even if GHG emission are reduced greatly we still have problems to face and so adapting is a very good idea.

    Comment by Jacob Mack — 20 May 2010 @ 5:54 PM

  281. When considering the issue of drought and extreme weather, it is important to realize that climate change can increase both drought AND flooding in the same location. If more precipitation falls in rare, severe events, it not only causes floods, but also erosion of topsoils. What it does not do is recharge aquifers.

    I saw a lot of this sort of weather when I lived in Africa–flooding in the monsoon causing erosion and washing away crops if it came in the wrong season, followed by bone-dry, dustbowl conditions–and all in a region that gets over a meter and a half of precipitation in a year!

    Comment by Ray Ladbury — 20 May 2010 @ 5:54 PM

  282. # 281 Excellent points. Well said. CFU pay attention to Ray’s post,as they get the point across in a real way:)We all learn from him.

    Comment by Jacob Mack — 20 May 2010 @ 6:06 PM

  283. re: #281
    Yes, and closer to home, this is exactly the issue that California runs into sometimes. Much of the state water infrastructure was deigned to depend on a huge natural reservoir, the Sierra snowpack. Warming makes a higher % of precipitation fall as rain, and makes the snow melt faster in the Spring, so it is quite possible to get both flood and drought. Since much of CA does *not* get a meter and a half, this matters… especially since ~half the US fruit and veggies are grown here.

    Comment by John Mashey — 20 May 2010 @ 6:36 PM

  284. # 283: Yeah I have lived here in California for the past 3 plus years now. Yet we still have an enormous amount of fruits and vegetables along with a crack team at Berkeley studying ways to keep agriculture thriving as it is gradually receding in its yields here.

    [Response: Er, no, that would be Davis, and some at Riverside.--Jim]

    Comment by Jacob Mack — 20 May 2010 @ 6:45 PM

  285. 269, CFU: “Ye shall know them by their fruits” (Matt 7:16 )

    Do you pay attention to what you write? You claimed to know my wishes.

    276, Ray Ladbury: Septic Matthew, allow me to translate CFU’s snark: I believe he means that you do not wish to know–and correspondingly that if you did wish to know, you could reach the same level of confidence (e.g. 90-95%) that countless scientists have reached before you.

    I think that translation is at variance with the actual language of his post. I agree that it may have been a snark instead of a thought.

    Comment by Septic Matthew — 20 May 2010 @ 6:53 PM

  286. Continuing comment #279: Didier Paillard then did the last 2 million years and it is clear he could have done the entire Quaternary. This required, it seems, rather more careful choices of mode switching values and characteristic time constants. In addition, the decline in average CO2 concentrations was mimicked by a linear increase in a mode switch constant; also a linear increase in solar insolation.

    Comparison between the calcuated values for v and a benthic d18O record is done by eye in both the time and frequency domains. By eye the time domains are similarly featured but more impressive is the striking agreement between the two evolutive spectra (wavelet transforms). The switch from obliquity period dominated cycling to the long period cycling of the last 1.1 million years occurs right on schedule. The other features of the evolutive spectra are in close agreement as well.

    Niether of the other two attempts I’ve read about even attempt this longer period analysis, so it is not clear that either would succeed. As it is, Didier Paillard’s model (so far) offers the more explanatory power.

    Comment by David B. Benson — 20 May 2010 @ 6:58 PM

  287. David tell us more; 2,000,000 years is a long time.

    Comment by Jacob Mack — 20 May 2010 @ 7:10 PM

  288. Papers citing Paillard’s 2001 paper “Glacial cycles: Toward a new paradigm”

    http://scholar.google.com/scholar?cites=8623472388026150541&hl=en&as_sdt=2000

    Comment by Hank Roberts — 20 May 2010 @ 7:37 PM

  289. Continuing comments #279 & #286: about 2000+ years ago, orbital forcing was close to the threshold for a switch from mode 0 (integlacial) to mode 1 (mild glacial) but of course that didn’t happen. Figure 3 in Archer & Ganopolski (2005) indicates that the threshold wasn’t reached in their analysis, irrespective of anthropogenic AGW. Crucifix * Rougier (2009) use a different climate model, nonlinear but without modes, and specifically test the hypothesis regarding a (mild) glacial at this time in the absense of AGW for the last 8000 years. That is, they stop parameter training at 8000 ybp and then extrapolate with those parameters; no glacial, even mild, until around 50–60 thousand years from now. That agrees with Archer & Ganopolski. But for a certain range of a threshold parameter value in Didier Paillard’s model, all mode transitions remain the same (for the past 900,000 years) except at the current time, when a mild glacial is underway in the model.

    So it might well be the case that anthropogenic influences on climate, even those of 2000+ ybp, were just enough to avoid such a transition. The low orbital forcing certainly helps to explain why the past two millennia are the coldest of the Holocene in the GISP2 central Greenland ice core proxy.

    Now one expects some phase lag between the forcing (orbital in this case) and the response (temperature). A lag of approximately 1610 years is plausible; the deep ocean responds only slowly. So in part, LIA might be attributed to an orbital forcing response.

    Comment by David B. Benson — 20 May 2010 @ 7:50 PM

  290. Most nonsensical cause of global warming I have heard so far: “Nuclear testing in the 1950s tilted the Earth’s axis.”
    We are up against some really strange ones. I hope I clarified the issue a little for him.

    Comment by Edward Greisch — 20 May 2010 @ 8:25 PM

  291. # 290 I know what you mean. Awhile back on Watts’s site some people had the audacity to state that since C02 is heavier than air it does not rise. Some really strange ones indeed.

    # 289 some interesting stuff, David and thank you Hank for some papers using the reference.

    Comment by Jacob Mack — 20 May 2010 @ 9:00 PM

  292. 222 Hank Roberts: Extreme hourly precipitation increase with increased temperature: Roger that. Maybe more. It rains a lot harder than it used to.

    Comment by Edward Greisch — 20 May 2010 @ 9:26 PM

  293. A very ironic point:

    What I don’t like about hypotheses (by “like,” I mean, like as a fit) for the Medieval Warming Periods and the Little Ice Age being to any great extent carbon-related points to the truth about those of us who accept the scientific consensus on what’s been going on the past 125 years or so. They say we’re radicals, but we’re scientific conservatives. We like robust models and clear theoretical approaches that fit in with as much of the existing body of knowledge as possible. It doesn’t seem to me that we really have a big gap with the MWP or LIA to explain, over and above what we know from the geological record. The disputes have been over magnitude, I think.

    I could add that we’re also on the conservative side of almost every battle here. Conserving species. Planning conservatively. Planning in a precautionary way. Assuming real income will be low, instead of high – that we’ll have to be frugal and efficient. Conserving our genetic heritage.

    The denialists, on the other hand, often resemble the pronouncements of the early Soviets – no problems projected, just follow our economic and political advice and Nature and the real world will be conquered, and we can grow without limits.

    I also agree with the comment early in this thread that if the MWPs and LIA were in fact substantially human and carbon-related, that is very bad news – good news, perhaps, for our credibility, although I wouldn’t bet on it, but terrible news for the future of humanity.

    Comment by Marion Delgado — 20 May 2010 @ 9:33 PM

  294. Jim and at Berkeley… you should not speak so soon.

    Comment by Jacob Mack — 20 May 2010 @ 10:10 PM

  295. James Hansen’s book: “Storms of My Grandchildren” must be read and OBEYED word for word by Congress. “Storms of My Grandchildren” has to become the law. Write and call and email as many senators as you can today and every day.

    Comment by Edward Greisch — 20 May 2010 @ 10:12 PM

  296. http://calclimate.berkeley.edu/publication/agriculture

    Relevant publications and references on the website, however, here is one example from Berkeley regarding the economic impacts of climate change on agricultural water use in California:

    http://calclimate.berkeley.edu/sites/default/files/13.%20Economic%20impacts%20of%20climate%20change%20on%20agricultural%20water%20use%20in%20CA.PDF

    Of side interest reported on by Berkeley:

    http://sciencereview.berkeley.edu/articles.php?issue=13&article=beespecies

    In addition to the aforementioned research out of Berkeley and reporting on agricultural–climate change issues there are many other publications, reports and primary research on the relevan topics coming out of Berkeley.

    [Response: Please, tell us more about the agricultural research coming out of the various units of the UC system...I mean, you've been in CA for 3 years now and all.--Jim]

    Comment by Jacob Mack — 20 May 2010 @ 10:23 PM

  297. http://www.cnr.berkeley.edu/csrd/global/flconf/ UC Davis is great too!

    Comment by Jacob Mack — 20 May 2010 @ 10:29 PM

  298. 269, CFU: “Ye shall know them by their fruits” (Matt 7:16 )

    I got to wondering: Was that an appeal to authority?

    276, Ray Ladbury: “Septic Matthew, allow me to translate CFU’s snark: I believe he means that you do not wish to know–and correspondingly that if you did wish to know, you could reach the same level of confidence (e.g. 90-95%) that countless scientists have reached before you.”

    If CFU’s comments require translation, shouldn’t you direct your remarks to him? (or her?)

    Comment by Septic Matthew — 20 May 2010 @ 11:10 PM

  299. “Do you pay attention to what you write? You claimed to know my wishes.”

    Yes and what you say and what you state as truth show those wishes. The fruits of your labour are your posts here on RC.

    All in denial of the problem.

    cf “the warming has paused” earlier from you. Can only be a product of wishful thinking.

    Comment by Completely Fed Up — 21 May 2010 @ 2:56 AM

  300. “When considering the issue of drought and extreme weather, it is important to realize that climate change can increase both drought AND flooding in the same location”

    Yah, now when did anyone say rain?

    There was already a drought.

    If it’s raining, there’s not a lot of drought going on.

    Comment by Completely Fed Up — 21 May 2010 @ 2:59 AM

  301. “# 278: No, not always, and not in the context of regional climate changes. Droughts worsened by warming probably will happen”

    They already have happened.

    Here, look at the graph of temperatures:

    http://data.giss.nasa.gov/gistemp/graphs/

    Warmer temperatures.

    When you already HAVE a drought, is it true or not that making it warmer makes the drought more severe.

    Answer that question.

    Seems nobody reads anymore.

    Comment by Completely Fed Up — 21 May 2010 @ 3:02 AM

  302. 174
    Completely Fed Up says:
    19 May 2010 at 11:46 AM

    Namjd, AGW is climate change. If there’s no climate change, there’s no AGW. Therefore to prove AGW you have to prove climate change.

    Therefore evidence for AGW is evidence of climate change.
    —————————–

    Of course there can be massive climate change without AGW, and you don’t need to prove that at all.

    Comment by John — 21 May 2010 @ 5:13 AM

  303. Since I’ve been less than clear about this above: I don’t claim that precipitation and evaporation are the only factors determining drought, or that warming will not bring drought if only there’s enough rain. I’m aware of the issues with the Palmer index (Brian Dodge #265). I’m also aware that precipitation increases and floods can very well go hand in hand with more or worse drought (for reasons pointed out by Ray Ladbury #281, John Mashey #273, and CFU #246).

    In the context of the recent Southeast drought and the Seager paper we were discussing, these points militate against complacency about the region’s future. (The cited projections of increased P and a “modest” reduction in P – E need not be understood as implying merely modest increases in drought risk).

    But do these points make a difference to the argument we were having over attribution?

    Comment by CM — 21 May 2010 @ 5:19 AM

  304. More “overt cheating” by climate change deniers: Easterbrook fakes his figures, hides the incline – http://bit.ly/a8Y6PZ

    Scott A. Mandia, Professor of Physical Sciences
    Selden, NY
    Global Warming: Man or Myth?
    My Global Warming Blog
    Twitter: AGW_Prof
    “Global Warming Fact of the Day” Facebook Group

    Comment by Scott A. Mandia — 21 May 2010 @ 6:14 AM

  305. “Awhile back on Watts’s site some people had the audacity to state that since C02 is heavier than air it does not rise. Some really strange ones indeed.”

    I’ve run into this one a couple of times–I think it’s been discussed here in the past. (Not that there’s all that much to say!) Seems it’s a minor recurrent (nutso) meme.

    Comment by Kevin McKinney — 21 May 2010 @ 6:58 AM

  306. “But do these points make a difference to the argument we were having over attribution?”

    Not really, CM, because we are still talking past each other.

    I’m saying you can attribute AGW as having made the drought worse than it would otherwise have been.

    Others seem to be obsessing over attribution of the CAUSE of the drought. Dry weather CAUSED the drought. AGW made the weather hotter.

    Again, I’ll pass you back to the 1999 cooler temperatures.

    If I were to state that 1999 was affected by increasing effects of AGW, this would not twitch an eyebrow.

    There would be only a few denier-types saying “wrong”.

    But it WAS cooler than 1998. Or 2003, etc.

    The effect of AGW on that years’ temperature is evidenced by still being warmer than the warmest year before 1985.

    Yet we don’t have Jacob saying AGW has had no effect on the temperature in 1999 because that year was within normal variation seen before, do we?

    Why here?

    Because (this is my intimation) people are asserting that somehow I’m saying that AGW caused this drought. And that I’m attributing the entire drought to AGW’s effects.

    I’m only attributing some of the dryness of the drought to AGW.

    That our models are not accurate enough in detail to attribute X drop in precipitation to weather events and Y drop in precipitation to climate change doesn’t mean that there was no effect from climate change.

    You see, I don’t disagree with those who say that AGW is not proven by one drought. I disagree with people saying I’m wrong in attributing some of the depth of the drought to AGW because the drought doesn’t prove AGW.

    Comment by Completely Fed Up — 21 May 2010 @ 8:08 AM

  307. “Of course there can be massive climate change without AGW, and you don’t need to prove that at all.”

    for Namij we do.

    How about you?

    What do YOU think has caused this climate change?

    Comment by Completely Fed Up — 21 May 2010 @ 8:09 AM

  308. “I got to wondering: Was that an appeal to authority?”

    No.

    It was an appeal to logic: if someone keeps saying stuff that means AGW is not a problem, and spouts lies about how temperatures have possibly paused (it hasn’t, as shown by actual evidence), then this logically means that the person continuing to avoid facing a problem does not WANT there to be a problem.

    Hiding their head in the sand.

    An appeal to logic.

    Comment by Completely Fed Up — 21 May 2010 @ 8:11 AM

  309. CFU “What do YOU think has caused this climate change?”

    Very honestly, if I didn’t read newspaper, I would have never thought there is a climate change at all. I have travelled all around the world, I’ve seen very different climates, and I do not know any place where the climate has changed following the usual taxonomy ( arctic, oceanic, continental, tropical, and so on…, or more precisely for instance the Köppen climate classification http://en.wikipedia.org/wiki/Köppen_climate_classification ).

    And this simply because I do not know any place in the world where “changes” have exceeded significantly ( statistically speaking ) the known natural, preanthropogenic, local variability. This is of course not incompatible with the fact that the global average has significantly changed, but this doesn’t imply that the LOCAL climates have changed. So your question is a kind of non sequitur.

    Comment by Gilles — 21 May 2010 @ 8:47 AM

  310. Again, Gullible doesn’t answer the question and takes paragraphs to do so.

    Comment by Completely Fed Up — 21 May 2010 @ 9:06 AM

  311. John (#302) You were saying..?

    Comment by Completely Fed Up — 21 May 2010 @ 9:10 AM

  312. Scott A. Mandia says: 21 May 2010 at 6:14 AM

    Easterbrook fakes his figures, hides the incline – http://bit.ly/a8Y6PZ

    And misspells “Younger Dryas”, which I was perversely delighted to see highlighted in the deconstruction.

    Definitely worth a look-see, though I have to say I’m beginning to feel pretty degraded by following some of this stuff and witnessing my own responses. Dr. Easterbrook was a prof of mine, way back when, and though I did not particularly bond to him I’m still kind of sorry to see what happens when emerititus gets a full grip on a formerly productive scientist.

    Comment by Doug Bostrom — 21 May 2010 @ 9:35 AM

  313. Gilles produces the true “non sequitur”:
    “Q: What has caused climate change?
    A: News stories.”
    How can the average change significantly without any of the individual points changing??

    Comment by flxible — 21 May 2010 @ 9:35 AM

  314. “How can the average change significantly without any of the individual points changing??”
    Think about it … (it’s not “without any of the individual points changing”, it is “without any of the individual points changing significantly”)
    Another thing is that “climate” is not a mere function of average temperature, but also of the amplitude of temperature variability, precipitations (both in amount and in repartition) , etc … Changes in the average temperature are far from catching the possible “climate change” and as far as I know, the changes observed in any of these parameters anywhere in the world are still far from producing a “different climate”.

    Comment by Gilles — 21 May 2010 @ 9:49 AM

  315. Ah, more word games, from Gilles (#309) this time. Gilles, you may want to familiarize yourself with the distinction between climate change and climate shift or climate regime shift as used by the IPCC.

    Comment by CM — 21 May 2010 @ 9:54 AM

  316. And this simply because I do not know any place in the world where “changes” have exceeded significantly ( statistically speaking ) the known natural, preanthropogenic, local variability. This is of course not incompatible with the fact that the global average has significantly changed, but this doesn’t imply that the LOCAL climates have changed. So your question is a kind of non sequitur.

    This just means that you’re out of touch with nature. Perhaps if you spent more time birding or gardening or the like, you’d be more perceptive of the local and regional changes people who are in touch with the world have seen over the past decades.

    Comment by dhogaza — 21 May 2010 @ 10:04 AM

  317. Gilles says: “Very honestly, if I didn’t read newspaper, I would have never thought there is a climate change at all.”

    Are you sure you’re not channeling Nixon? Maybe if we all just close our eyes and wish with all our might, it will go away, huh?

    Actually, we can tell a lot about Gilles from this statement:
    1)He doesn’t garden.
    2)He’s not very observant
    3)He loves word games.

    Comment by Ray Ladbury — 21 May 2010 @ 10:21 AM

  318. CM et al, Gilles has shown why Jacob’s statement is wrong and why I argued it that way.

    “it’s not “without any of the individual points changing”, it is “without any of the individual points changing significantly””

    That’s exactly what Jacob said.

    And Gilles is wrong as Jacob is wrong: if you increase the effect on ANY event (e.g. you’re God) by 4% then the chance of getting an event weaker than the previous average is ~48%. Therefore you’d need ~400 events to note the change and ascertain it was a 4% increase.

    EVEN THOUGH you have not, by the time 20 events have occurred been likely to see anything outside the normal range of events.

    Yet there HAS been an effect.

    Comment by Completely Fed Up — 21 May 2010 @ 10:56 AM

  319. 314 Gilles said, “it is “without any of the individual points changing significantly”)” and ““climate” is not a mere function of average temperature”

    Most points have to change significantly for the average to change significantly.

    Raise the temperature a bit and the arctic sea ice melts, creating an ocean where effectively land used to exist. The gross functioning of climate systems will change.

    Comment by RichardC — 21 May 2010 @ 11:17 AM

  320. 317: Ray said Gilles is not very observant. etc.

    I’ll tell you what I saw recently that blew me away. Rain. Hard driving rain. An hour after sunset. At 10,000′ in the Rocky Mountains. In February. Over the last two decades I’ve watched the winter rain. Twenty years ago we didn’t get winter rain at all. Then, we started seeing the occasional rain shower at 5,500′, but much above that we’d get only snow. Then eventually we started seeing gully washers at 5,500′. Then we started getting rain showers at 7,200′. Then gully washers at 7,200′. This year was the first time I ever saw winter rain at 10,000′. That rain did turn to snow later on that evening, but jimminy, it was pouring rain at 10,000′ in the Rocky Mountains in the dead of winter an hour after sunset. I know. I know. I can’t attribute the weather trend I’ve observed to global warming.

    Comment by John E. Pearson — 21 May 2010 @ 11:29 AM

  321. re: #296
    OT, but in the interests in peace in CA…
    jacob:
    I’m a 27-year CA resident who’s given talks at UCBerkeley, UCDavis, UCLA, UCSD, UCSB, at least, and grew up on a farm, and attended Penn State, which has a not-bad ag school. I’ve been at UCB more often, and UCB is a great school, with a fine Ag Econ department (not the same thing), BUT if you actually visit places, great ag schools tend not to be located in dense urban areas…

    UC Davis includes one of the *top* ag engineering schools:

    US News&World Report, tied for #4 (and I’ve visited 10 of the top 12 schools). Compare:
    Davis:
    Among the top five in the nation, according to The Chronicle of Higher Education’s “Top Research Universities Faculty Scholarly Productivity Index 2007,” these doctoral programs:

    * Soil Science: #1
    * Entomology: #1
    * Plant Pathology: #2
    * Evolutionary Biology: #2
    * Agricultural and Resource Economics: #2
    * Animal Biology: #3
    * Horticulture and Agronomy: #3
    * Biological Sciences: #4″

    UCD is especially famous for its oenology, but really, it is one of the very top schools in the world in agricultural research.

    Comment by John Mashey — 21 May 2010 @ 11:30 AM

  322. UCD is especially famous for its oenology

    I’ll drink to that!

    Comment by dhogaza — 21 May 2010 @ 11:53 AM

  323. dhoganza @ 316:

    This just means that you’re out of touch with nature. Perhaps if you spent more time birding or gardening or the like, you’d be more perceptive of the local and regional changes people who are in touch with the world have seen over the past decades.

    It’s also possible this is the result of a psychological process known as the “least perceptible change”. It’s why you don’t notice gradual changes in people until they’ve reached some point of changing.

    If he’s traveling as much as he indicates, it’s possible that he’s confusing seasonal variations with climate variations. It took me three or four winters of not wearing heavy coats to realize that it had been three or four winters.

    Even with birding and other nature activities, it’s easy to miss a major change unless you take notes and compare what you saw one season to what you see this season.

    Comment by FurryCatHerder — 21 May 2010 @ 12:11 PM

  324. BY the way, if anyone knows where to get monthly rainfall data at specific places in the Rocky Mountains I’d love to see it. I’ve made a few half-hearted attempts to find rain-fall data but have found only monthly precipitation data in which no distinction is made between rainfall and snowfall. My belief is that high alititude winter rain in the southern rockies was exceedingly rare until recently and that it is now growing in frequency but I have nothing to support that assertion other than my own observations.

    Comment by John E. Pearson — 21 May 2010 @ 12:14 PM

  325. If it’s raining, there’s not a lot of drought going on.

    Drought is insufficient rain.

    Comment by Jeffrey Davis — 21 May 2010 @ 12:20 PM

  326. Watch the farm report “Ag Day” on TV. Right now we are having both regions of drought and regions of crops washed away by too much rain. They showed drought regions on a map. There are many regions of each. The regions are not all concentrated in one corner of the map. Regions alternate between too much and too little rain. Of course the regions will be different at another time.
    Theorists: Please watch Ag Day. You need the ground truth.

    Comment by Edward Greisch — 21 May 2010 @ 12:36 PM

  327. jim, i have friends born and raised in california who graduated Berkeley. There are also plenty of publications out of Berkeley. Iam not sure why you insist on being cofrontational and sarcastic over a well established fact. I have been to Berkeley many times and they are not just an econ school.

    [Response:Well, because you don't know what you're talking about, but think and talk like you do, and I don't much care for that type thing. Davis has been the ag school from its earliest inception as the university farm, producing huge volumes of peer-reviewed, applied research results for decades, particularly with respect to plant agriculture. Most people know this. There's absolutely no comparison to the gray papers and committee reports and other whatnot that you linked to from Berkeley, which focuses mainly on policy and economics and has NO agricultural departments. But believe whatever you want. And all further comments on this topic are OT--Jim]

    Comment by jacob mack — 21 May 2010 @ 12:49 PM

  328. “325
    Jeffrey Davis says:
    21 May 2010 at 12:20 PM

    If it’s raining, there’s not a lot of drought going on.

    Drought is insufficient rain.”

    That is right, captain obvious.

    Now, look again: that was said to someone who said that rain was important to forming a drought.

    Not when the drought is already there: the rain situation is already set: not enough.

    PS I note that you didn’t actually find where someone talked about how the drought was caused by AGW.

    Epic Fail.

    Comment by Completely Fed Up — 21 May 2010 @ 1:02 PM

  329. Even with birding and other nature activities, it’s easy to miss a major change unless you take notes and compare what you saw one season to what you see this season.

    Gardeners and birders tend to be record keepers, which is one reason I mentioned both of those. Or, if one doesn’t keep one’s own records, one tends to depend on those kept by others, such as those that lead to the delineation of horticultural zones and recommended plantings and times to plant here in the US, bird guides with seasonal range maps, etc.

    Comment by dhogaza — 21 May 2010 @ 1:08 PM

  330. FurryCatHerder says: 21 May 2010 at 12:11 PM

    If he’s traveling as much as he indicates, it’s possible that he’s confusing seasonal variations with climate variations. It took me three or four winters of not wearing heavy coats to realize that it had been three or four winters.

    It’s a creeping sort of thing, on a time scale we’re not good at working with and besides that highly susceptible to our malleable memories.

    I finally (thank you, flying spaghetti monster or whatever) returned to the Seattle area after a multi-decade excursion through parts East. Seattle of course is notorious for rain, but in my early memory it’s fixed as mostly continuous drizzle during the fall and winter months.

    I could -swear- now that I’m back I’m seeing a lot more drenching rain, episodic showers that remind me of what I see upslope on the windward side of the Big Island out in Hawaii though not of course as intense. Our house here had its bottom floor inundated in a storm in December of 2007 before we’d managed to move in, the most recent of several 25, 50 or 100 year events packed into a relatively brief period.

    Is this climate? Is my memory correct? All I can really do is rely on statistics, big collections of events carefully recorded. So looking to my own experience although Gilles is terribly annoying in many ways I think his personal observations are entirely plausible.

    Fortunately we don’t have to rely on our own anecdotes, our flexible and suggestible memories. There’s a mass of statistics telling us our intuitive noses are probably smelling something real. But if mental comfort is what we want, we can train ourselves to find it, make our memory work for what we want.

    Comment by Doug Bostrom — 21 May 2010 @ 1:15 PM

  331. http://enviro.berkeley.edu/researchcent

    http://bwc.berkeley.edu/home/

    I love RC and I do not want to continue in a conversation that is fruitless,
    but again all the relevant links to UC Berkeley research, and I am done.

    [Response: Not relevant and OT]

    Comment by Jacob Mack — 21 May 2010 @ 1:21 PM

  332. John, have you looked for streamflow data? That would change dramatically with a change from snowfall to rainfall. Here for example (just an example, you can find much more):
    http://journals.ametsoc.org/doi/full/10.1175/JCLI3321.1
    Journal of Climate 2005; 18: 1136-1155
    Changes toward Earlier Streamflow Timing across Western North America
    “The highly variable timing of streamflow in snowmelt-dominated basins across western North America is an important consequence, and indicator, of climate fluctuations. Changes in the timing of snowmelt-derived streamflow from 1948 to 2002 were investigated in a network of 302 western North America gauges by examining the center of mass for flow, spring pulse onset dates, and seasonal fractional flows ….”

    Comment by Hank Roberts — 21 May 2010 @ 1:30 PM

  333. Regarding Ag Engineering….I notice that University of Illinois in Urbana is ranked Number 1! Glad I have all three of my degrees from UI.

    http://www.universityportal.net/2008/03/top-university-of-agricultural.html

    That is where I started research in manure biomethane mitigation back in 1979. They are doing some outstanding work in practical applications of climate change mitigation, it’s a fun place to hang out. Unfortunately, the state of Illinois is flat broke, and the UI is in turmoil lately. Biomass happens I guess.

    Comment by CRS — 21 May 2010 @ 1:43 PM

  334. #309 Gilles

    Your supposition is based on your opinion, not the measured (statistically significant) changes that are actually occurring. You see, it does not matter what you think, it matters what is actually happening.

    Here are only ‘some’ things that are happening that is measured by observation indicating climate shift:

    - Altitudinal shift
    - Latitudinal shift
    - Seasonal shift
    -Migration times
    - Fire seasons
    - Planting times
    - Soil moisture content
    - Humidity factors: global, latitudinal and regional
    - Arctic ice loss
    - Global deglaciation
    - Antarctic ice extent increase vs. Antarctic ice mass loss
    - Drought trends based on trend and forcing
    - Changes in radiative forcing

    Well, this is just the short list. Back in reality, your opinion or perspective means nothing when weighed against actual changes around the world.

    All you have really proven is that your perspective is inadequate to the task at hand. I hope you are not in a position of serious importance. Incompetence in capacity of understanding is not a desired trait in a position of responsibility, especially if it has to do with the well being of the public.

    By the way, why don’t you post your full name again?

    #314 Gilles

    The political term Gilles is waving here is “as far as I know”. Goodness, could we get a little more wiggle room in here. . . oh never mind, there’s enough.

    John Coleman has begun using that phrase as well. . . how convenient. Kind of an attorney General Gonzales moment.

    Back in reality, you obviously know very little on this subject.


    A Climate Minute The Greenhouse EffectHistory of Climate ScienceArctic Ice Melt

    ‘Fee & Dividend’ Our best chance for a better future – climatelobby.com
    Learn the Issue & Sign the Petition

    Comment by John P. Reisman (OSS Foundation) — 21 May 2010 @ 1:43 PM

  335. CFU #306, let’s try again.

    > I’m saying you can attribute AGW as having made the drought worse than
    > it would otherwise have been.

    I’ll nearly agree with you: You can attribute AGW as having made a drought more likely to happen or to be worse than it would otherwise have been.

    To the extent one cannot say of a specific weather event that it was caused by anthropogenic climate change/global warming, I think one also cannot say that the event was made worse by AGW. Both the event happening, and its intensity, could always be “just weather”. What one can say, if the models so suggest, is that climate change increased the risk of the event occurring, or increased the risk of the event being worse. If by warming the planet we made an unlikely extreme event hugely more likely to happen, then there is at least a statistical sense in which we can reasonably attribute the event at least in part to AGW without worrying about the philosophical niceties of whether it was “caused” by AGW. (Cf. <a href="http://www.nature.com/nature/journal/v432/n7017/abs/nature03089.html"Stott et al. 2004, discussed by Gavin on an earlier thread).

    From what I’ve read here, though, it seems the Southeast drought was not all that unlikely an event. and that the models do not project a very strongly AGW-increased risk of drought in the Southeast. Don’t ask me to quantify but I’d doubt you could make such an attribution significant.

    I also don’t follow your argument upthread that “there already was a drought, warming made it worse” (or words to that effect). AGW does not only affect temperatures and leave other things the same. It also tends to influence such things as how much rain falls where. So if a heatwave is not just weather, but weather that has been made more likely to happen by AGW, by the same token a lack of rain has also been made more or less likely by AGW. And if the models say AGW makes the precipitation extreme that caused a drought less likely, the drought will be harder to attribute to AGW.

    Can we end it about here?

    Comment by CM — 21 May 2010 @ 2:00 PM

  336. “You can attribute AGW as having made a drought more likely to happen or to be worse than it would otherwise have been.”

    I’ll go along with that.

    I would add that, absent any detail of how it didn’t make it worse, the default would be it did make it worse.

    Note: Frank would call you completely and utterly wrong in your statement.

    The reasoning for that proviso I added is the same that would be the basic nullity that AGW uses: CO2 is a greenhouse gas, we’re adding CO2 to the atmosphere, we’re warming the atmosphere, we’re warming the planet.

    The arguments against the conclusion there are the same ones you need for my proviso: it’s possible that it is false, but the burden is on you to show it false.

    Comment by Completely Fed Up — 21 May 2010 @ 3:21 PM

  337. “I think one also cannot say that the event was made worse by AGW. Both the event happening, and its intensity, could always be “just weather”.”

    I still say you have this wrong and you should prove it. All you’ve managed is to state it. And again I would pass this on to an analogy that you must deal with:

    Is the 1999 temperature NOT affected upward by the excess of CO2 humans have placed in the atmosphere over the preceeding 12 decades?

    I say yes.

    What do YOU say?

    Comment by Completely Fed Up — 21 May 2010 @ 3:24 PM

  338. “AGW does not only affect temperatures and leave other things the same. It also tends to influence such things as how much rain falls where”

    So show that AGW shifted rain into SE US and made drought there less.

    That would be proof.

    What RodB produced in #116 was not.

    (yes that’s really the same thing said three times, but maybe one of them will make my position click)

    Comment by Completely Fed Up — 21 May 2010 @ 3:42 PM

  339. Doug Bostrum: “So looking to my own experience although Gilles is terribly annoying in many ways I think his personal observations are entirely plausible.”

    Of course his ‘personal observations’ are “plausible”, the problem is they are those of a short term flyby, simply noting that the nominal “regional climatic classification” still holds, like the arctic is colder than the tropics, which in turn are hotter than the temperate zone …. well la-te-da.

    Had he spent 5 or 10 continuous years in any of the places he’s traveled to, he might have a bit more perspective on what global climate change means to any single regional climate.

    Being a bit north of you, for the last 35+ years straight, I’ll confirm your observation that the PNW rain patterns are different than they have been historically, but Gilles on his holiday would observe that the regional climate is as it has always been “Köppen climate classified”, dry-summer subtropical or Oceanic. Meaningless regarding global climate change.

    Comment by flxible — 21 May 2010 @ 3:50 PM

  340. Maybe OT :-)

    Do recent study’s in past climate still confirm that the MWP was rather regional then global?

    Are there new study’s wich give more clarity in the forcings wich lead to the strong warming from about 1910 till about 1945?

    How is the devolepment in the “bucket-question” (stark cooling about 1945).

    If Pinabo wouldn’t have happenened would temperatures be much higher?

    Same question for the of polution wich caused the temperatures to be flat from about 1948 untill 1978?

    Regards

    Comment by Ibrahim — 21 May 2010 @ 4:21 PM

  341. flxible says: 21 May 2010 at 3:50 PM

    True enough, stand in any one spot and one’s effective latitude still appears to be shifting, these days.

    Interesting what you say about rain. The point I was thinking about but failed to properly express was that having grown up here and become accustomed to typical weather and then left for a long time, when I returned it seemed like there was a distinct difference and this was perhaps easier to see because I was familiar with the old yet was not continuously exposed to a slow change which thus might fade into imperceptibility. Which of course feeds into remarks about Gilles being itinerant and thus not really well equipped to judge his surroundings.

    But I may be a particularly oblivious person so I’m happy that longitudinal data is available to test my perceptions against.

    Comment by Doug Bostrom — 21 May 2010 @ 4:41 PM

  342. Gilles: http://www.shiftingbaselines.org/videos/index.html
    Of course you don’t notice change. It takes reading and recordkeeping to notice change.

    Comment by Hank Roberts — 21 May 2010 @ 4:46 PM

  343. CFU try reading the IPCC report

    Comment by jacob mack — 21 May 2010 @ 5:24 PM

  344. Mr David Benson

    William Happer says:
    “Additional increments of CO2 will cause relatively
    less direct warming because we already have so much CO2 in the atmosphere that it has blocked most of the infrared radiation that it can. The technical jargon for this is that the CO2 absorption band is nearly “saturated” at current CO2 levels. Adding more CO2 is like putting an additional ski hat on your head when you already have a nice warm one below it, but you are only wearing a windbreaker.”

    Which is like what I posted some time back., to which you replied – “read the IPCC AR4″.

    I will read it thoroughly (I have mainly read and tried to understand paleo chap 6). But you should be able to answer this simple query, in the light of such proclamations which repeatedly do pop up:

    If all these bigshot scientists are saying this about the CO2 GHG effect yield, there must be some truth to it.

    [Response: A touching thought, but unfortunately one that is not borne out by the facts. Happer is just wrong. The forcing from increasing CO2 is roughly 5.3*log(CO2/CO2_o) which is not zero, and indeed is roughly equivalent to the increase of forcing of just under 2% in solar irradiance. Or is that negligible as well? - gavin]

    Does it not, then follow, that an MWP-LIA CO2 dip (whatever the cause be), have a greater contribution to temperatures, than increases in CO2 have on warming today?

    Comment by Anand — 21 May 2010 @ 6:22 PM

  345. Anand: do you know that Will Happer is the Chairman of the George C. Marshall Institute, and this is rather more relevant to his testimony than his work at Princeton? The CEO of GMI is William O’Keefe, a 25+-year veteran of the American Petroleum Institute. If this is unknown to you, but you actually want to understand, try PDF here.

    Happer also stated that polar bears will be just fine, so will corals, and any concern over global warming is like Prohibition.

    Comment by John Mashey — 21 May 2010 @ 7:44 PM

  346. #334 – John P. Reisman

    I don’t understand what you mean by “Antarctic ice extent increase”. I’ve had a subscription of National Geographic’s Desk Diary since 1998. In the back are maps, one of which is of Antarctica. I placed the 1998 and 2010 page sized maps side by side and did a comparison. The changes over the last dozen years are quite dramatic:

    West Ice Shelf – Narrowed by around 1/4 to 1/3 from its 1998 size.

    Shackelton Ice Shelf – There was an ice peninsula in 1998 which is now a nub and the other end has narrowed.

    Cape Poinsett to Porpoise Bay – The widest part is gone, and the once continuous ice shelf is now two separate ice shelves.

    Glacier West of the Magnetic South Pole – In 1998 there was a small glacier in a small bay, in 2010 there is now an ice peninsula extruding from Wilkes Land. This is the only growth I noticed and it is a calving glacier….

    Ross Ice Shelf – It has receded to Roosevelt Island.

    Larsen Ice Shelf – The northern most section has narrowed and the already narrow part around Mt. Jackson is gone.

    Ronne Ice Shelf – It has recede, but less than the other large ice shelves.

    Coats Land to American Highland – This part of the coast line appears to be holding its own with regard to the ice shelves.

    #309 Gilles – “And this simply because I do not know any place in the world where “changes” have exceeded significantly ( statistically speaking ) the known natural, preanthropogenic, local variability.”

    The above is a lot of change in only 12 years.

    Comment by Jason Miller — 21 May 2010 @ 7:48 PM

  347. Googling global warming and the hydrologic cycle is also helpful. The water encyclopedia discusses most of the issues we have in terms of precipitation,droughts.crop yields,and thelike. UC Davis has some great research published on how some plants temporarily grow larger and then stagnate and sometimes die due to the C02 inhibiting nitrate formation of proteins. UC Berkeley has excellent research published in Bio engineering and Bio meteorology regarding preserving crop yields, predicting future yields and weather patterns. The IPCC report is clear on probable worsening of both floods and droughts. Also discussed are areas in upper latitudes where crops will more likely grow due to a warmer climate. An article from1985 published in Nature asserted that AGW was outpacing plant life evolutionary adaptations. In some current research this does not completely hold. Two possible explanations are punctuated equilibrium and more mild adverse regional weather changes in select locations.Africaispronetofloodsanddrou

    Comment by jacob mack — 21 May 2010 @ 8:06 PM

  348. > Jason Miller
    > Antarctic sea ice

    Distinguish sea ice from ice shelves.

    This explains the observed change in Antarctic sea ice, as predicted:
    http://moregrumbinescience.blogspot.com/2010/03/wuwt-trumpets-result-supporting-climate.html
    This charts the trend:
    http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.anomaly.antarctic.png

    Comment by Hank Roberts — 21 May 2010 @ 8:10 PM

  349. Anand says, “If all these bigshot scientists are saying this about the CO2 GHG effect yield, there must be some truth to it.”

    Interesting.

    So why do you choose to believe the few “bigshot scientists”–most of them ad libbing well outside their expertise–rather than the thousands of scientists who actually publish in climate science?

    Why do you choose to believe a tiny minority of “bigshot scientists” rather than every profesional organization of scientists that has taken a position on the subject?

    Why do you choose to believe a few “bigshot scientists” rather than the National Academy of Sciences, which reiterated its concern–and much more forcefully than ever before–just the other day?

    And most of all, why do you choose to believe a handful of “bigshot scientists” instead of the evidence?

    Interesting, don’t you think?

    Comment by Ray Ladbury — 21 May 2010 @ 8:57 PM

  350. Ray:
    I think like you too.

    You have thousands on one side. Among them, not all are experts on the CO2 radiative forcing property. That is only a handful. Happer’s credentials are in the same area of research.

    He makes this statement to the Congress. This same statement was made by Lindzen.

    That is why I ask.

    Gavin: Are you saying that all you need is that one formula to warm up the climate? I always thought the sensitivity of the climate to CO2 is an inferred value.

    [Response: No. But you quoted a statement about saturation - which goes to the issue of forcing, not response. If co2 was saturated, the forcing would be negligible. It isn't. What the response might be is a wholly different question, and which neither you nor Happer got to. - gavin]

    Trenberth has argued that some heat has gone ‘missing’ Is it possible that some heat went missing in the LIA and then turned up again into the account during the late 20th century?

    Comment by Anand — 21 May 2010 @ 10:17 PM

  351. #349 – Hank Roberts

    Thank you for posting the links above and clearing up my confusion. I had not heard about this.

    Comment by Jason Miller — 21 May 2010 @ 10:24 PM

  352. Mr. Jason Miller says on the 21st of May 2010 at 7:48 pm

    “…maps, one of which is of Antarctica. I placed the 1998 and 2010 page sized maps side by side and did a comparison”

    I must recommend this exercise. I have on my wall, a world map published by the Defense Mapping Agency of the USA in 1975. It includes the summer and winter sea ice extent lines as they were then, many ice shelves that no longer exist, a non shrunken Aral Sea…

    It is quite shocking to compare that map with the reality today.

    sidd

    Comment by sidd — 21 May 2010 @ 10:38 PM

  353. Anand says: 21 May 2010 at 6:22 PM

    Saturation? That argument is an anachronism, put in its grave some time ago right here at RC among other places.

    Yet another volunteer supplied with yet another comic rubber chicken to wave about. Demand a better prop; those folks meeting in Chicago are paid to freshen their act from time to time.

    Comment by Doug Bostrom — 21 May 2010 @ 11:06 PM

  354. re: #350
    Anand :
    1) Can you cite which of Happer’s papers you think are relevant, and explain why?

    2) I watched Happer (not a biologist) explain why polar bears will be just fine and (not a coral expert) explain that ocean acidification wont’ bother corals.

    3) As I suggested in #345, do you yet understand the nature of GMI?
    If you don’t want to read what I suggested, in just a few days, Merchants of Doubt, by Naomi Oreskes and Erik Conway, will be available, and you can read that.

    Happer’s predecessors in that job were experts, so he had good trainers.

    You might want to read The Daily Princetonian’s interview with him. That’s the one that quotes him:
    “This is George Orwell. This is the ‘Germans are the master race. The Jews are the scum of the earth.’ It’s that kind of propaganda,” Happer, the Cyrus Fogg Brackett Professor of Physics, said in an interview. “Carbon dioxide is not a pollutant. Every time you exhale, you exhale air that has 4 percent carbon dioxide. To say that that’s a pollutant just boggles my mind. What used to be science has turned into a cult.””

    Comment by John Mashey — 21 May 2010 @ 11:54 PM

  355. Re #344 Anand,
    It seems to me that to say the atmosphere is saturated with CO2 is a silly thing to say! Something obvious: the atmosphere declines in density with altitude. What this means is that even if CO2 was saturated (in terms of radiative effect) at sea level it will not be at some altitude above sea level. If I am wrong please let me know.

    Comment by Lawrence McLean — 22 May 2010 @ 12:57 AM

  356. #348 Hank Roberts

    Re. Jason Miller #346

    Thanks Hank :)

    Jason, it may be that you were looking at data or images from Antarctic minimums for southern hemisphere at max melt?

    Remember, context is key.


    A Climate Minute The Greenhouse EffectHistory of Climate ScienceArctic Ice Melt

    ‘Fee & Dividend’ Our best chance for a better future – climatelobby.com
    Learn the Issue & Sign the Petition

    Comment by John P. Reisman (OSS Foundation) — 22 May 2010 @ 1:24 AM

  357. Also an interesting article. Let me know if the link does not work, as there is free access online:

    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2848572/pdf/pone.0009932.pdf/?tool=pmcentrez

    Comment by Jacob Mack — 22 May 2010 @ 1:41 AM

  358. “343
    jacob mack says:
    21 May 2010 at 5:24 PM

    CFU try reading the IPCC report”

    And what am I going to read there except that AGW causes, globally, warming? Which is what I’ve been saying and you’ve been refusing to accede.

    Why try to throw me on a wild goose chase when you refuse to answer my rather simple queries?

    Because you don’t like the idea that we are being affected by climate change, though you’ll admit (if you have to) that there is climate change going on. Just not in any one event.

    Comment by Completely Fed Up — 22 May 2010 @ 3:08 AM

  359. “340
    Ibrahim says:
    21 May 2010 at 4:21 PM”

    Go to the Start Here page. Or

    http:/www.ipcc.ch

    Comment by Completely Fed Up — 22 May 2010 @ 3:10 AM

  360. Gilles 309: Very honestly, if I didn’t read newspaper, I would have never thought there is a climate change at all. I have travelled all around the world, I’ve seen very different climates, and I do not know any place where the climate has changed following the usual taxonomy ( arctic, oceanic, continental, tropical, and so on…, or more precisely for instance the Köppen climate classification http://en.wikipedia.org/wiki/Köppen_climate_classification ).

    And this simply because I do not know any place in the world where “changes” have exceeded significantly ( statistically speaking ) the known natural, preanthropogenic, local variability.

    BPL: As a French citizen, you may not know about the imported Chinese vine, kudzu, which has devastated much of the American southeast for the past century or so.

    It has now been reported in Pennsylvania, New York, Maine, and Ontario.

    Look at a map to see why that indicates climate change.

    Comment by Barton Paul Levenson — 22 May 2010 @ 5:00 AM

  361. Ibrahim 340,

    Mt. Pinatubo depressed world temperatures by about 0.3 K for two years.

    Comment by Barton Paul Levenson — 22 May 2010 @ 5:30 AM

  362. Anand, Happer’s expertise is atomic and molecular physics, not climate or atmospheric physics. His thinking on the matter is quite shallow, actually, giving no indication that he has ever undertaken serious study of climate.

    Lindzen is another matter. He has fallen in love with the idea of strong negative feedback giving rise to an ultra-stable climate–despite there being no evidence in favor of the idea and plenty of paleoclimatic evidence against it. Why he has fallen in love with the fallen idea, I do not know. Some of his writing on the subjece gives an impression that he believes in the strong anthropic principle.

    Lindzen is worth listening to. He is still trying to play the game–although his rejection of CO2 as a climate driver makes it very difficult for him to contribute. Happer is talking out of an alternative orifice.

    Comment by Ray Ladbury — 22 May 2010 @ 7:19 AM

  363. #345–

    Yes, carbon dioxide is a natural component of the atmosphere.

    So is nitrogen. In fact, nitrogen is the main component of the atmosphere. Like carbon, it is necessary to many life forms. The latter point can be made about phosphorus, which, like carbon dioxide and nitrogen, can act as a fertilizer–and, like nitrogen in fact, is sold commercially for precisely this purpose.

    None the less, nitrogen and phosphorus can act as a pollutant when present in excessive quantities in the wrong places. You could make analogous points for NaCl, too, and I’m sure for other substances.

    So why do folks like Happer–who presumably should know better–want to treat CO2 differently than these other natural-and-necessary-substances-which-nevertheless-can-pollute?

    http://www.epa.gov/waterscience/criteria/nutrient/

    Comment by Kevin McKinney — 22 May 2010 @ 7:33 AM

  364. 332: Thanks Hank. Excellent thought.

    Comment by John E. Pearson — 22 May 2010 @ 7:56 AM

  365. There is still at least one fly in the ointment regarding natural explanations of the MWP/LIA cooling. That view says or implies that a natural cooling drove the observed CO2 drop (~10 ppm) from ~1200 to 1700. Estimates of the (N Hem) cooling over that interval range from ~0.2C (Mann) to ~0.5C (Moberg). Carbon-climate models suggest that the sensitivity of CO2 to temperature forcing is around 10 ppm per degree C. The model estimates range widely, but that seems to be the consensus number. If so: the estimated cooling can explain a CO2 decrease of about 2-5 ppm out of the 10 ppm observed.

    The same problem arises for the interval 1500-1650. The estimated cooling (0.15-0.4C) explains just 1.5-4 ppm out of a measured CO2 drop close to 10 ppm (and sustained at 5-7 ppm until 1750).

    So: if most of the measured CO2 response was not natural in origin, how complete is our understanding of this interval? I said this in my 2003 ‘Early anthropogenic’ paper, but it seems to have drawn little attention, except from Nevle/Bird.

    Comment by Bill Ruddiman — 22 May 2010 @ 8:07 AM

  366. Mr Ruddiman:
    Your books are always checked out at the library. I hope to read them soon. ;)

    Re you CO2 sensitivity to temperature:
    Frank et al (2010) estimate gamma to be much greater (by a factor of 10) in cooling phases than in warming phases. Their estimate is in the order of 40 ppm CO2 per degree.

    [Response: Anand, why do you say this? Did we not go over this at length in the discussion at that time? There was no stated relationship between the direction of temperature change and the magnitude of gamma, and Frank et al. did NOT find a gamma of 40 ppm/degree when temperatures were cooling. Furthemore, the higher values of gamma associated with the rapid CO2 drop in the late 16th C should not really be considered as gamma values if land cover changes were in fact responsible, because gamma attempts to estimate sensitivities independent of such confounding factors. Please go back and re-read.--Jim]

    Perhaps CO2 solubility/sinks behavior in cooling phases has been underestimated.

    Regards

    Comment by Anand — 22 May 2010 @ 10:44 AM

  367. Response to #366:

    Frank et al gave a best estimate of 8.8 ppm CO2 change per degree C, which is even lower than the 10 ppm/C that I cited, so it would explain even less of the observed CO2 drop. They do estimate a higher sensitivity (roughly a doubling) during the cooling after 1550, but they don’t explain why the sensitivity would have changed at that time. Cox and Jones, Science Sept 19, 2008 suggest a very high sensitivity like the one you mentioned for the interval 1550-1800, but again don’t say why the system sensitivity would abruptly go up by a factor of four or more compared to ‘normal’. There is a serious danger of circular reasoning here— deriving a very high sensitivity from the observed temp/CO2 trends in order to explain a CO2 drop that the normal sensitivity cannot explain. In contrast, if most of the CO2 drop is anthropogenic (the American pandemic and demographic collapse), then the normal sensitivity would still apply over that interval.

    Comment by Bill Ruddiman — 22 May 2010 @ 11:46 AM

  368. John Mashey (345), is this the old ‘if you can’t refute the science conjecture, at least show that he hangs around with ugly people” argument??

    Comment by Rod B — 22 May 2010 @ 12:10 PM

  369. CFU spewed: “CFU try reading the IPCC report”

    And what am I going to read there except that AGW causes, globally, warming? Which is what I’ve been saying and you’ve been refusing to accede.”

    I have always stated that AGW increases global warming. Or, in your language causes new warming that is NOT due to natural variations. You have no evidence to support this claim.

    CFU: “Why try to throw me on a wild goose chase when you refuse to answer my rather simple queries?”

    No wild goose chase; some areas of drought will be worsened by AGW, some will not; some areas as Ray Ladbury stated have drought and flooding in a very short span of time. Again you are making this up CFU.

    CFU: “Because you don’t like the idea that we are being affected by climate change, though you’ll admit (if you have to) that there is climate change going on. Just not in any one event.” AGW is a fact CFU and I have stated so numerous times. Of course we are and will be affected by climate change. My only point is you are hypoer-fcoused on droughts alone, and this is a gross oversimplification of the issues of AGW.

    Prediction is still somewhat troubled and attributions range from being very statistically significant to not so much.

    Please read a little more carefully my posts and references I leave. Pay attention to Ray and Hank’s posts as well. Inferential statistics is by its very nature interpretive and probabilistic.

    Comment by Jacob Mack — 22 May 2010 @ 12:52 PM

  370. Yeah guys there is no scientific basis for saturation of CO2 in the atmosphere whatsoever, so can we get off that topic?

    Comment by Jacob Mack — 22 May 2010 @ 12:54 PM

  371. CFU: “Warmer temperatures.

    When you already HAVE a drought, is it true or not that making it warmer makes the drought more severe.

    Answer that question.

    Seems nobody reads anymore.”

    Global warming can sometimes does and will make some droughts more severe, but as the wold wams some areas prone to droughts will on average have more rainfall with inceased evapoation. Also some regional weather conditions will change, possibly cooler in some regions.

    Back to Ray’s example of monsoons and drought in Africa; this is certainly detimental as most of us agree, but not necesaaily in terms of worse doughts alone.

    p.s. AGW has both negative and positive consequences, but the majority seem to be more negative in the majority of regions. Still some polar regions along with others in North America will benefit in several ways, but desrtification is a real issue in already dy and aid climates.

    Comment by Jacob Mack — 22 May 2010 @ 12:59 PM

  372. Jason Miller (346) Graphs from the U of Illinois show very little difference in ice extant in Antarctica — virtually zero anomaly the past 30 years, though with noticeable annual variation. These graphs have large granularity and may not readily show the changes you’re talking about. They also measure sea ice which I am assuming is what shelves are. Comment on these two points?

    There does seem to be agreement that the average temperatures around the coast of Antarctica (though not the interior and, curiously, not north into the Southern Ocean) have increased in recent decades and that ice shelves are, on the whole, losing mass. The coastal temp increase is much greater than what the average global temperature has been; it is also close to H2O freezing normally so it doesn’t take much to rise above freezing. But there is serious disagreement as to whether this is due to AGW or just regional natural variance. For example warmer Antarctic temperatures ought to increase ice mass from increased precipitation.

    Comment by Rod B — 22 May 2010 @ 2:37 PM

  373. Doug Bostrom (353) says, “Saturation? That argument is an anachronism, put in its grave some time ago right here at RC among other places.”

    For the record (my broken one to be precise) put in its grave with convenient (though maybe reasonable) hypotheses as opposed to irrefutable physics. It’s not obvious who is waving a comic rubber chicken. (Is that like a strawman???)

    Comment by Rod B — 22 May 2010 @ 2:48 PM

  374. Lawrence McLean (355), theoretically if CO2 did absorb all of the radiation in its absorption band, then no matter how much CO2 was at higher altitudes it would have no radiation to absorb. This is an oversimplification of what actually happens but does address your point in the main.

    Comment by Rod B — 22 May 2010 @ 2:58 PM

  375. Jacob Mack (287) — What more would you like to know?

    I realize I know of another paper which I now ought to reread to add to the three considered so far.

    Comment by David B. Benson — 22 May 2010 @ 3:15 PM

  376. 360 Barton Paul Levenson: It [kudzu] has now been reported in Pennsylvania, New York, Maine, and Ontario.

    Look at a map to see why that indicates climate change.

    That is an interesting comment. Within the last 100 years most of the American chestnuts of the northeast have died of natural causes and the remainder are severely diseased. Is there evidence that the spread of kudzu is not also due to random variation and natural selection? The stuff grows and reproduces rapidly, so spreading (as with XDR TB) is inevitable with time unless native browsers start preferring it as food.

    Comment by Septic Matthew — 22 May 2010 @ 3:35 PM

  377. Regarding C02 saturation, reading Spencer Weart puts the final nail in that coffin.

    Comment by jacob mack — 22 May 2010 @ 3:46 PM

  378. > most of the American chestnuts of the northeast have died
    True
    > of natural causes
    False, and you can look it up

    > Is there evidence that the spread of kudzu is not also due to
    > random variation and natural selection?
    Yes, and you can look it up.

    Good grief.

    Comment by Hank Roberts — 22 May 2010 @ 4:32 PM

  379. Oh, let me correct myself; only the above-ground part of the chestnuts after five or six years old dies. http://www.acf.org/

    Comment by Hank Roberts — 22 May 2010 @ 4:33 PM

  380. David B. Benson, # 375: any information and references you have would be most helpful; thanks in advance.

    Comment by Jacob Mack — 22 May 2010 @ 4:52 PM

  381. 376 Matthew asked, “Is there evidence that the spread of kudzu is not also due to random variation and natural selection?”

    Kudzu can’t take a very hard frost. A good hard killing frost would still kill off any kudzu in Maine.

    Comment by RichardC — 22 May 2010 @ 5:11 PM

  382. “theoretically if CO2 did absorb all of the radiation in its absorption band, then no matter how much CO2 was at higher altitudes it would have no radiation to absorb.”

    Theoretically, the CO2 at the higher altitudes would have the radiation from the saturated CO2 at the lower levels to absorb…

    Energy is not destroyed, you know…

    Comment by Completely Fed Up — 22 May 2010 @ 6:55 PM

  383. “Global warming can sometimes does and will make some droughts more severe,”

    So show it happened with the SE US drought.

    Comment by Completely Fed Up — 22 May 2010 @ 6:56 PM

  384. Jacob, I’ve read the IPCC.

    It seems you haven’t if you think they say that no drought has been affected by AGW…

    Comment by Completely Fed Up — 22 May 2010 @ 6:58 PM

  385. “Prediction is still somewhat troubled and attributions range from being very statistically significant to not so much.”

    Uh, show how the CO2 didn’t warm the SEUS, jacob.

    IT HAD AN EFFECT.

    PS you’re still avoiding answering my questions.

    Comment by Completely Fed Up — 22 May 2010 @ 7:00 PM

  386. E. Tziperman, M. E. Raymo, P. Huybers, C. Wunsch, 2006. Consequences of pacing the Pleistocene 100 kyr ice ages by non linear phase locking to Milankovitch forcing (pdf), Paleoceanography convincingly demonstrate that very many nonlinear systems of equations are capable of approximating, rather well, a d18O compilation for the past 900,000 years. So just matching such a proxy does not facilitate the selection of one model over another in a highly robust way. I take the conclusions to imply that the use of such models says essentially nothing about the question of whether or not AGW avoided a glacial at the present time.

    The situation isn’t quite that bad in that prehaps various information criteria, AIC or BIC, might aid in model selection. Even better, I opine, would be to follow on from the use of CO2 is Crucifix & Rougier (2009) to devise a conceptual model which tracks both CO2, maybe aslo CH4 and a choice of d18O conpendium of the interval for which CO2 records are available from Antarctic ice cores. Even then answers to the avoidance question are likely to be model dependent.

    Comment by David B. Benson — 22 May 2010 @ 7:31 PM

  387. Hi, RodB.

    The Saturated Gassy Argument appears not to be required in order for researchers to continue producing findings consistent with hypotheses constructed without it.

    Thus it seems reasonable to conclude that while possibly not lying cold in its grave, the Saturated Gassy Argument is elsewhere and playing no active role. Possibly it is even poolside at a conference in Chicago sipping from a drink with a tiny umbrella and doing nothing while everybody else is hard at work. Yet nobody notices; its absence from duty has no measurable effect so it’s quite safe to say that the Saturated Gassy Argument is not necessary to better scientific understanding of climate and thus is irrelevant.

    Regarding rubber chickens, I’m still struggling to find exactly the right metaphor for the sort of weapons being handed to volunteers stepping forward to defend industrial interests with a need to maintain the status quo in terms of fossil fuel consumption.

    Comment by Doug Bostrom — 22 May 2010 @ 7:41 PM

  388. Rod B., you need to review:
    http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument/

    http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument-part-ii/

    It is irrefutable that CO2 radiates as well as relaxing collisionally.

    It is irrefutable that absorption lines broaden with pressure and velocity.

    It is irrefutable that CO2 is a well mixed, long-loved greenhouse gas well into the stratosphere.

    Any model starts out as a series of “convenient assumptions”. Once they are verified by the predictive power of the model, they cease to be merely assumptions. It’s called science.

    Comment by Ray Ladbury — 22 May 2010 @ 7:47 PM

  389. 376, Septic Matthew–

    Yes, there is evidence. The historic spread pattern correlates very well with the temperature record. If you link back on RC, you should be able to find references.

    The recent news on this topic was the publication in PNAS of Lerdau, 2010, which showed that kudzu infestation significantly raises tropospheric ozone levels in summer–enough to cause public health impacts.

    Kudzu has now been found in Canada (Leamington, Ont–where a lot of my mom’s family went to high school) and in Maine. The Canadian find was just last year, and has prompted the issuance of alerts to try and prevent the plant from becoming established.

    Comment by Kevin McKinney — 22 May 2010 @ 9:00 PM

  390. Mr. John P. Reisman ( 22 May 2010 @ 1:24 AM),

    I did not understand when you said “Antarctic ice extent increase” in #334 that you meant the extent of sea ice. I thought you were implying the ice shelves and glaciers were expanding, thus the subsequent post. Mr. Hank Roberts pointed out at #348 that you were referring to sea ice and provided links. I had not considered sea ice before. So yet another item has been added to the list of things I need to learn more about concerning climate change.

    Comment by Jason Miller — 22 May 2010 @ 9:02 PM

  391. Well, this symposium powerpoint has some pretty good analysis on kudzu & temps, too:

    http://www.newss.org/symposium/ziska1_climate_symposium.pdf

    Comment by Kevin McKinney — 22 May 2010 @ 9:27 PM

  392. “long-loved greenhouse gas”

    I love CO2!

    Comment by Anand — 22 May 2010 @ 9:35 PM

  393. One last kudzu link: this is the one John Mashey originally provided; it actually includes some lab work, they actually chilled/froze kudzu stems, measured tissue damage and subsequent growth if any. You can see they drew on the Ziska work linked above.

    http://www.stewardshipcentre.on.ca/files/scnON/3501_Sage_Bioinvasives_and_Global_Change.pdf

    Bottom line: I think the temperature/kudzu range link looks pretty damn solid. (As well as being eminently sensible in the first place.)

    Comment by Kevin McKinney — 22 May 2010 @ 9:37 PM

  394. > Rod B says: 22 May 2010 at 2:58 PM
    > Lawrence McLean (355), theoretically if CO2 did absorb all
    > of the radiation in its absorption band

    In your theory, the CO2 would do what with all this absorbed energy, Rod?
    Tuck it away into some string theorist’s extra curly hidden dimension?

    Comment by Hank Roberts — 22 May 2010 @ 9:48 PM

  395. re: 376 Septic Matthew
    Back in #206, I posted a pointer to a nice presentation on kudzu by Toronto researchers. You don’t need to perform onerous research, like looking in Wikipedia or looking for research papers, that presentation ought to do it, and they actually have better maps. Hopefully, you will read that and return, saying “yes, that is convincing evidence from people who actually study it.”

    Comment by John Mashey — 22 May 2010 @ 9:50 PM

  396. It is irrefutable that CO2 is a well mixed, long-loved greenhouse gas well into the stratosphere.

    I assume that was a typo for “long-lived” – or have you gone over to the “CO2 is life” side, Ray? ;-)

    Comment by CTG — 22 May 2010 @ 10:11 PM

  397. CFU (382), agreed, but that was left out of my maybe over simplification for clarity.

    Comment by Rod B — 22 May 2010 @ 10:23 PM

  398. Ray Ladbury (382), I concur with all of your statements. My assertions of the “less than irrefutable” are based on the degree or the differential of the functions.

    Comment by Rod B — 22 May 2010 @ 10:31 PM

  399. CFU learn how to read please. Obviously I know AGW can affect droughts and increase the probability of worse droughts. I answered all of your questions as well. CFU, are you high or something?

    Comment by Jacob Mack — 23 May 2010 @ 12:15 AM

  400. Not every drought is made worse, yes you know that. Also some droughts are made less severe or reversed by FLOODING. Some droughts are made less severe by some moderate rain due to evaporative processes. I cannot fathom how you got from my posts that I thought NO droughts would be worse. My statement to you originally was to the effect that a drought discussion alone is getting out of hand. There are better ways to see highly correlated evidence in AGW than droughts or hurricanes at this point. Not all droughts are made worse when it gets warmer: fact. Not all droughts which may be more severe can be attributed to AGW with great confidence: fact. The IPCC report discusses more severe and frequent droughts, floods, dying crops, better growing crops, more possible farming in higher latitudes, more and larger pests threatening crops, etc, all facts.

    CFU one thing is clear to me that you have no college degree in anything and on that note I am done with this topic on droughts which you give more attention than it is due.

    Comment by Jacob Mack — 23 May 2010 @ 12:22 AM

  401. Rod 368,

    No, it’s the old pointing-out-that-crackpots-in-one-area-often-embrace-other-pseudosciences-as-well argument.

    Comment by Barton Paul Levenson — 23 May 2010 @ 5:04 AM

  402. Rod 373,

    Put in its grave through high-altitude spectral observations made during World War II. Please read:

    http://BartonPaulLevenson.com/Saturation.html

    Comment by Barton Paul Levenson — 23 May 2010 @ 5:05 AM

  403. “CFU (382), agreed, but that was left out of my maybe over simplification for clarity.”

    You mean you left the reason why your statement was wrong to make it clearer?

    Weird.

    So apart from the radiation of the layer below, there’s no radiation for the CO2 in the upper layer to trap is basically what you’re saying.

    Well apart from the food I’ve eaten, I’ve never ate a bite of food in my life. Ergo, I’ve just proved you don’t have to eat anything to live!

    Comment by Completely Fed Up — 23 May 2010 @ 6:24 AM

  404. “CFU (382), agreed, but that was left out of my maybe over simplification for clarity.”

    You mean you left the reason why your statement was wrong to make it clearer?

    Weird.

    So apart from the radiation of the layer below, there’s no radiation for the CO2 in the upper layer to trap is basically what you’re saying.

    Well apart from the food I’ve eaten, I’ve never ate a bite of food in my life. Ergo, I’ve just proved you don’t have to eat anything to live!

    Isn’t proof easy when you simplify by leaving stuff out!

    PS Why are you simplifying when you then state in 398 that the “problem” with CO2 saturation is about a DETAIL in calculation???

    Comment by Completely Fed Up — 23 May 2010 @ 6:27 AM

  405. Hey Rod B,

    “Ray Ladbury (382), I concur with all of your statements. My assertions of the “less than irrefutable” are based on the degree or the differential of the functions.”

    Is this denier-ese for “Sorry, I was wrong” ???

    Comment by Joe Cushley — 23 May 2010 @ 6:33 AM

  406. Rod, you might want to reserve the technobabble for some site where people don’t speak real technical language. I’m sorry, but your use of “degree” and “differential” isn’t meaningful here.

    Comment by Ray Ladbury — 23 May 2010 @ 9:02 AM

  407. CFU (belatedly — sorry),

    #336: I agree that the burden of proof today lies on those who deny we are warming the planet by emitting CO2. I don’t think the same applies to the attribution of a particular drought event even though global warming is pushing us towards more drought on the average.

    #337: “Is the 1999 temperature NOT affected upward by the excess of CO2 humans have placed in the atmosphere over the preceeding 12 decades?”

    Sure, it was. Put another way, the global mean temperature of 1999 was very unlikely to have been as high in the absence of human CO2 emissions. (A temperature that high doesn’t show up in the first 110 years of the GIStemp record, and yet by 1990s standards, 1999 wasn’t even particularly warm!) The global mean temperature is on an undisputable upward trend and formal attribution studies have shown human fingerprint. A regional event is a different matter.

    #338: “So show that AGW shifted rain into SE US and made drought there less.”

    I wasn’t claiming it did, I was arguing a general point; sorry if that wasn’t clear. “There is no clear evidence of hydroclimate change in the Southeast during the period of anthropogenic forcing of climate” (Seager et al.). As noted before, models project increased precipitation in the near term future but this is more than balanced by increased evaporation; the 2005/6 drought did not fit this pattern (ibid.).

    Your turn: do you think anthropogenic warming made made the 2005 drought in the Southeast US worse than it would have been around, say, 1901? (Yes, this is a trick question — see the left-hand map in AR4 fig. 3.9.)

    Comment by CM — 23 May 2010 @ 9:39 AM

  408. Barton Paul Levenson #361

    CFU#359

    Thank you for you answers.

    I know enough.

    Regards

    Comment by Ibrahim — 23 May 2010 @ 11:09 AM

  409. Hank (394) actually my simple hypothetical example does not require the low level CO2 to do anything with the absorbed energy. But (still keeping it (over?)simple) the energy would transfer to other gases through collision.

    Comment by Rod B — 23 May 2010 @ 1:37 PM

  410. CFU, I was simply trying to answer a basic question with a clear and simple answer. I wasn’t explaining radiation physics or the entire atmospheric processes re GHGs.

    The detail in calculation (your words) response was to a totally different post. Try to keep things straight.

    Comment by Rod B — 23 May 2010 @ 1:49 PM

  411. Ray Ladbury (406), if you don’t understand differentials and how they (it) relates to forcing ala AGW then I am blown away. Take any 1st year calculus on your way to PhD land? Though my point (which I mentioned just for the record; we’ve all been through it before and I didn’t intend to resurrect it just now) is simply that the forcing equation for CO2 as it goes from say 350ppm to 700ppm because of anthropogenic emissions has never been observed, even by proxy, nor tested nor irrefutably (totally is probably a better word) explained with physics. Which, BTW, is a differential.

    Comment by Rod B — 23 May 2010 @ 2:03 PM

  412. Rod B, that sort of technobabble only works on the pre-school readers.

    The mechanism was understood and calcualted in 1950′s.

    Oh and as to “the forcing equation for CO2 as it goes from say 350ppm to 700ppm because of anthropogenic emissions has never been observed”

    a) Equations have never been observed. Not even F=ma.

    b) We are observing the effect of the log dependence of CO2 to forcings

    Comment by Completely Fed Up — 23 May 2010 @ 3:34 PM

  413. “I don’t think the same applies to the attribution of a particular drought event even though global warming is pushing us towards more drought on the average.”

    CM, still you make this.

    WHO IS ATTRIBUTING something to a particular drought? *I* *am* *not*.

    I repeat

    I

    AM

    NOT

    So why do you continue to argue as if I am?

    Comment by Completely Fed Up — 23 May 2010 @ 3:35 PM

  414. “Your turn: do you think anthropogenic warming made made the 2005 drought in the Southeast US worse than it would have been around, say, 1901?”

    If we had had AGW at the same level of accululated effect, yes, it would.

    (note: your trick question is not a trick one because the 1901 event was a weather event that AGW would have added to, thereby making it worse).

    Comment by Completely Fed Up — 23 May 2010 @ 3:37 PM

  415. > But (still keeping it (over?)simple) the energy would transfer
    > to other gases through collision.

    No photons emitted in all directions including up and down?
    One way transfer of energy away by collision, but not back?

    If you rule out the other known energy transfers to and from CO2, what remains is indistinguishable from magic.

    Comment by Hank Roberts — 23 May 2010 @ 3:38 PM

  416. “400
    Jacob Mack says:
    23 May 2010 at 12:22 AM

    Not every drought is made worse, yes you know that”

    But you seem to consider it impossible to say that a drought is made worse by AGW.

    Now, come back and get to the FRIGGING POINT:

    SE US Drought.

    Was that made worse by AGW.

    ME: Yes.

    You?

    Comment by Completely Fed Up — 23 May 2010 @ 3:42 PM

  417. “I answered all of your questions as well. CFU, are you high or something?”

    Are you? Certainly seems like when you’ve asserted so strongly you’ve answered all my questions. Hallucinations are a common consequence of drug abuse:

    Post #239:

    OK, peeps. A poll.

    Indicate which ones you agree with by listing as

    YES: # # #

    and which you disagree with by listing as

    NO: # # #

    1) AGW (climate change) creates warmer weather.

    2) Warmer weather makes drought more severe.

    3) Droughts are made more severe if you increase temperatures.

    Which ones are agreed as correct and which ones as wrong?

    (merely one example amongst several)

    Then again you don’t listen, you merely pontificate Jacob, and assume a position to me that you can attack.

    Comment by Completely Fed Up — 23 May 2010 @ 3:47 PM

  418. Rod B you again try to rewrite history and hope that nobody checks (a quite Republican way of arguing: bald faced lies knowing that nobody is checking).

    Post 397: CFU (382), agreed, but that was left out of my maybe over simplification for clarity.

    But in post 410 you complain that that was about something else other than CO2 saturation.

    Well 398 was this: Theoretically, the CO2 at the higher altitudes would have the radiation from the saturated CO2 at the lower levels to absorb…

    Which was about CO2 and your assertion that this was saturated and unable to affect climate change.

    There was nothing there about another post.

    Did you think nobody would check???

    Comment by Completely Fed Up — 23 May 2010 @ 3:51 PM

  419. CM: “Put another way, the global mean temperature of 1999 was very unlikely to have been as high in the absence of human CO2 emissions… The global mean temperature is on an undisputable upward trend and formal attribution studies have shown human fingerprint. A regional event is a different matter.”

    No, a regional event is NOT a different matter.

    What do you think happened to all those CO2 molecules over, say, the central US?

    Do you think they went away somewhere? Maybe shuffled off to Canada and Greenland to increase the warming there?

    No. CO2 is well mixed.

    Maybe the photons that came up from the US Soil was not in the range that CO2 traps, therefore there was no effect from CO2′s greenhouse effect?

    No, it’s the same mud as everywhere else. Thermodynamic laws did not decide to take a vacation.

    If you have no change in the events, how can you change the sum of those events?

    You can’t.

    You’re wrong.

    Comment by Completely Fed Up — 23 May 2010 @ 3:56 PM

  420. “because of anthropogenic emissions has never been observed, even by proxy, nor tested nor irrefutably (totally is probably a better word) explained with physics. Which, BTW, is a differential.”

    No, it’s a blue.

    WTF?!?!?

    Seriously, did you verb your nouns just there SERIOUSLY???

    No, science is not a differential.

    No, observation is not a differential.

    Cue The Humpty-Dumpty Defence: differential means what I mean it to mean, no more and no less.

    Comment by Completely Fed Up — 23 May 2010 @ 3:58 PM

  421. CM # 407 all well stated and accurate. Of course sometimes more precipitation due to evaporation has other effects at times as observed.

    Comment by Jacob Mack — 23 May 2010 @ 4:02 PM

  422. Rod, is it possible you mean “a derivative?”

    Comment by Barton Paul Levenson — 23 May 2010 @ 4:40 PM

  423. 413: BPL I have no idea what he is talking about. It is pure gibberish.

    Comment by John E. Pearson — 23 May 2010 @ 4:59 PM

  424. re: 401 BPL
    “No, it’s the old pointing-out-that-crackpots-in-one-area-often-embrace-other-pseudosciences-as-well argument.”

    Actually, unlike, say Arthur Robinson, candidate for the US House in Oregon’s 4th district, and known to RC readers, I do not think Happer fits that. I think he is more in the Seitz/Jastrow/Nierenberg mold, in which a serious scientist holds intense political/ideological views that seem to cause them to abandon scientific thinking in any science whose results conflict with their other views. Then, they use their (legitimate) science credentials to claim expertise far beyond their own.

    One more time, Happer is Professor of Physics @ Princeton, and a NAS member, neither of which tend to be true of most lovers of pseudoscience.

    But since 2006, he has been Chairman of GMI, and a Board member for years before. About a page and a half of CCC Report is devoted to him, and Table A.6.2 (a) shows his long participation in various activities, including signing the OISM Petition.

    As of today, the 2nd item at GMI Home page says:

    “Institute Chairman Dr. Will Happer was a witness before the House Select Energy Independence and Global Warming Committee in a May 20 hearing titled “Climate Science in the Political Arena.” The video is available here.” (Although the video (at Markey’s site) isn’t actually there yet, but it will show up, I assume).

    Happer’s testimony only identifies him as:

    “William Happer Cyrus Fogg Brackett Professor of Physics
    Princeton University”

    It also says:

    “The views I express today are my own, and not official views of my
    main employer, Princeton University, nor of any other organization with which I am associated.”

    I certainly believe his views are not official views of Princeton … but if people peruse the GMI website, my CCC report, or the imminent Oreskes/Conway “Merchants of Doubt”, they can assess whether or not his views represent the Institute of which he is Chairman…and whose funding is interesting.

    (But sadly, none of this has anything to do with the interesting topic of the original post, which likely has a lot to do with resolving some differences amongst proxy-based temperature reconstructions and reducing uncertainty ranges.)

    Comment by John Mashey — 23 May 2010 @ 5:42 PM

  425. CFU when I have more time to look over data/papers, then maybe I will have an answer for that region, but it may still be speculation:)

    Comment by Jacob Mack — 23 May 2010 @ 10:07 PM

  426. CFU,

    #413: You have not been attributing the severity of the drought to AGW? Sorry. Uhm, what are we discussing?

    #414: But if the map I pointed you to can be explained as you say by a fin-de-sièclespell of warm weather, maybe the 2005/6 drought could be just regional weather too, and as likely to happen in the absence of AGW?

    #417 (poll): In the global mean, yes. Most of the time, in most places.

    Hey, if we know nothing more about a drought event than that it happened somewhere in the 2000s, it seems reasonable to me, based on what we know in general, to start out assuming that AGW made a significant contribution to the probability of that event. It seems imprudent to press that claim in debate, though, at least until studies have confirmed a significant link between that event and AGW, and unreasonable to continue pressing it if they fail to do so.

    #419: Strawman. CO2 is well-mixed and radiative forcing works the same everywhere. That was never at issue. And yet, surface temperatures do not respond uniformly. Let alone rainfall patterns, etc.

    Comment by CM — 24 May 2010 @ 3:57 AM

  427. “#413: You have not been attributing the severity of the drought to AGW? Sorry. Uhm, what are we discussing?”

    *I* have been discussing that AGW has affected and worsened the SE US drought.

    I haven’t attributed that drought to AGW.

    “#414: But if the map I pointed you to can be explained as you say by a fin-de-sièclespell of warm weather, maybe the 2005/6 drought could be just regional weather too”

    No, that is only a non-AGW effect if the effects of AGW on that region was to introduce rainfall that otherwise would not have entered the system.

    Back again to the 1999 temperature.

    HYPOTHESIS:

    Weather made that temperature 0.2C cooler than normal. The effects of trapped heat by CO2 and other greenhouse gasses increased that by 0.5C. Net effect: ~0.3C warmer than normal, but 0.2C cooler than the times around it.

    If the AGW effect had NOT been evident, the temperatures in 1999 would have been around that of 1920.

    “#417 (poll): In the global mean, yes. Most of the time, in most places.”

    I’ve used this before, so here it is again:

    Get a Random Number generator.

    Collect 30 value pairs (x,y) such that x=0-29 and y=Rand(30)-15+x.

    Look at the numbers.

    Even though you see numbers in the latter half of the series that are within the 90% confidence limits of the first 10 numbers, thereby leading you, Jacob and Gilles to consider that those numbers were not affected by the monotonically increasing effect of x, you KNOW (because it’s in the equation), each and every value is affected and increased by an upward trend…

    The regional effect is only cancelled if the changes engendered by AGW makes entrainment of colder air into the region feasible AND that the warming that allowed that entrainment has not increased the temperature over the median climatological value of the region it has been moved into.

    “Hey, if we know nothing more about a drought event than that it happened somewhere in the 2000s, it seems reasonable to me, based on what we know in general, to start out assuming that AGW made a significant contribution to the probability of that event.”

    That’s certainly one option, where you wish to show that a NEW DROUGHT was caused by AGW.

    However, I’m not talking about CAUSING one. I’m talking about making one that would have existed ANYWAY worse.

    Take, as an example, the Sahel.

    Already bone dry.

    It won’t be made much more “droughty” by AGW. It’s already pretty maxed out on the drought thing.

    But it WILL get hotter because of AGW.

    The number of occurrences may be no more, but it will still be affected by AGW because the ones that are there are worse.

    NOTE: This is very much the reason that fella who disagreed with the IPCC on hurricane FREQUENCY would be unaffected, as opposed to the IPCC consensus report that said it would. His position was that the number of events would not change markedly, but the severity for any event that was going to happen anyway (even sans AGW) would be worse.

    “#419: Strawman. CO2 is well-mixed and radiative forcing works the same everywhere. That was never at issue. ”

    No, it wasn’t a strawman, it was an argument by illogical extreme.

    If more heat was retained in the central US (for example), then although the WEATHER may have a colder state for a short time (e.g. El Nino/La Nina), if AGW hadn’t been there, the WEATHER at that region and time would have been colder yet.

    Therefore AGW affected that region by warming it, even though the WEATHER variation added a cooling term that overwhelmed the smaller but persistent warming climate effect.

    Comment by Completely Fed Up — 24 May 2010 @ 9:29 AM

  428. PS This: “#413: You have not been attributing the severity of the drought to AGW? Sorry. Uhm, what are we discussing?”

    Is not what I responded to. I responded to #407: “I don’t think the same applies to the attribution of a particular drought event”

    Note: NOTHING about “attributing the severity” in that version.

    Comment by Completely Fed Up — 24 May 2010 @ 10:25 AM

  429. 427 CFU. Single events are random within a single reality. If we had another reality, where AGW didn’t exist, then weather would be different from the beginning of where AGW didn’t start, and by now everything would be completely different.

    Comment by RichardC — 24 May 2010 @ 11:20 AM

  430. CFU (418), Oh, Paleeezze! I’m impressed. Turning two separate rather simple posts/comments into a convoluted integrated mess ain’t easy.

    Comment by Rod B — 24 May 2010 @ 11:25 AM

  431. BPL, here’s my dictionary.
    Noun: differential
    1) The result of mathematical differentiation; the instantaneous change of one quantity relative to another; df(x)/dx
    2) A quality that differentiates between similar things
    3) A bevel gear that permits rotation of two shafts at different speeds; used on the rear axle of automobiles to allow wheels to rotate at different speeds on curves
    Adjective: differential
    1) Relating to or showing a difference
    2) Involving or containing one or more derivatives

    Comment by Rod B — 24 May 2010 @ 11:33 AM

  432. > it wasn’t a strawman, it was an argument by illogical extreme.

    Comment by Hank Roberts — 24 May 2010 @ 12:08 PM

  433. One more time, Happer is Professor of Physics @ Princeton, and a NAS member, neither of which tend to be true of most lovers of pseudoscience.

    I know lots of scientists who believe all sorts of crazy shit outside of their field.

    This is way OT so if you must delete, delete away, but it’s sort of interesting anyway.

    Shoot. I almost got converted to belief in water-witching a while back. I had to locate the main waterline between my house and the meter. The pipe was plastic so they couldn’t run a current through it and measure the field. The guy who came out bent a coat hanger and started wandering around. Every time he passed over the spot where I’d told him i thought the pipe must run the coat hanger deflected downwards, pointing towards the spot where I thought the pipe was. It was an astonishing site to behold. For several seconds I believed he had found the pipes by water witching. Then my rationalist self took back over and I told the guy “you found the pipe where i said it was. I want confirmation or I don’t pay.” Later on the plumbers came and dug up the pipe starting at the meter and working their to the driveway. It was ten feet up the concrete driveway from the spot where the water witcher had claimed it was. He was simply confirming my bias.

    Comment by John E. Pearson — 24 May 2010 @ 12:29 PM

  434. Yes Hank. When a position is logical, it’s hard NOT to use an argument that shows the illogical extreme.

    And CM, you never used “attribution of severity” before until you pretended to quote me.

    Comment by Completely Fed Up — 24 May 2010 @ 12:29 PM

  435. Rod B., Physics is a differential? Do tell. You are talking out your ass and then denying it. You have thereby graduated to the level of “not even wrong”. We can do experiments in the lab that show that CO2 does not saturate. We know CO2 radiates as well as relaxing by collision. The fact is that Happer, in his testimony is full of a brown messy substance that is the product of normal metabolic processes. I find it hard to believe that he is not a good enough physicist to know he is wrong. You have a ways to go before you even rise to the level of wrong.

    Comment by Ray Ladbury — 24 May 2010 @ 12:43 PM

  436. > When a position is logical, it’s hard NOT to use an argument
    > that shows the illogical extreme.

    It’s hard. Please try harder.

    “It is a good example of the ‘old’ way of doing science.
    http://web.sbu.edu/history/tschaeper/Hist101/101wwwfbacon.html

    Comment by Hank Roberts — 24 May 2010 @ 1:00 PM

  437. OK, Hank. Here’s the facts:

    1) CO2 is well mixed.
    2) CO2 is a greenhouse gas.
    3) We produce lots of CO2.
    4) Conclusion: AGW means we’re retaining more energy therefore warming.

    Yup?

    Now, how can that NOT warm a region unless 1 is false and therefore that region is UNAFFECTED by CO2 therefore AGW hasn’t warmed that place?

    That is the ABSOLUTE conclusion of CM’s attempt to wave off my position with “The global mean temperature is on an undisputable upward trend and formal attribution studies have shown human fingerprint. A regional event is a different matter.”.

    The ONLY way that makes ANY sort of counter to my position is if it is promoting the fact that AGW doesn’t affect regions, only globes.

    Comment by Completely Fed Up — 24 May 2010 @ 1:25 PM

  438. Rod B, #430, I note that you fail to actually point to where your defense of your indefensible statement as “not to do with CO2 saturation” was “meant” to go.

    You’re busy waving your hands going “this is not the statement you read”.

    It should be FAR easier for the person who MADE the statement to show where the statements were “meant” to apply.

    Yet you haven’t managed yet.

    The smokescreen isn’t working.

    Comment by Completely Fed Up — 24 May 2010 @ 1:28 PM

  439. “Noun: differential”
    “1) The result of mathematical differentiation; the instantaneous change of one quantity relative to another; df(x)/dx”

    That’s not a science.

    “2) A quality that differentiates between similar things”

    That would be “differentiator”, not “differential”.

    I’ve just realised: this isn’t from a standard dictionary, is it, Rod.

    “3) A bevel gear that permits rotation of two shafts at different speeds; used on the rear axle of automobiles to allow wheels to rotate at different speeds on curves

    This isn’t science either.

    “Adjective: differential”

    If it’s an adjective, where’s the noun this is emphasizing? “a differential” is not grammatically correct.

    Guess your grammar is not standard either.

    “1) Relating to or showing a difference”

    This again would be “differentiator” or “difference” in more common parlance.

    “2) Involving or containing one or more derivatives”

    Maths. Again.

    Comment by Completely Fed Up — 24 May 2010 @ 1:37 PM

  440. “429
    RichardC says:
    24 May 2010 at 11:20 AM

    427 CFU. Single events are random within a single reality.”

    Good job I had my shades on there, I could have been blinded.

    _Yes_, I _know_.

    Now each single event is acted upon by one or more forces, yes?

    Why isn’t AGW one of them? Or does it not affect any single event, just the aggregate?

    Comment by Completely Fed Up — 24 May 2010 @ 1:39 PM

  441. I realize it is awful to actually discuss the topic of the post, but it is actually interesting.
    Consider the various reconstructions that cover, say 1500AD-1700AD.
    They vary somewhat (although generally within the envelope from MBH99).
    There are at least several possible reasons:
    a) Different selections of proxies.
    b) Different calibrations of them.
    C) Different statistical techniques for combining them.

    Can people point at studies trying to sort out the reasons for the differences?

    (This is all related to a conjecture that there might be different regional fingerprints for different combinations of causes for the AD1600ish drops in CO2 and temperature.)

    [Response: This is basically the question investigated by Rutherford et al (2005) [Rutherford, S., Mann, M.E., Osborn, T.J., Bradley, R.S., Briffa, K.R., Hughes, M.K., Jones, P.D., Proxy-based Northern Hemisphere Surface Temperature Reconstructions: Sensitivity to Methodology, Predictor Network, Target Season and Target Domain, Journal of Climate, 18, 2308-2329, 2005] available here. – mike]

    Comment by John Mashey — 24 May 2010 @ 1:43 PM

  442. 440 CFU said, “Now each single event is acted upon by one or more forces, yes? Why isn’t AGW one of them? Or does it not affect any single event, just the aggregate?”

    We have two timelines. One is AGW, the other is one where we avoided AGW. Each single event occurs in only one of the timelines. The AGW timeline will have worse droughts on average, but a single drought in AGW time might not even exist in no-AGW time, and vice versa.

    Comment by RichardC — 24 May 2010 @ 2:12 PM

  443. CFU, you are asserting the overgeneralization this post tries to address:

    “one thing is often lost in the discussion: space matters as much as time. Indeed, it is likely that the regional patterns of past climate changes, rather than simple hemispheric or global mean temperature trends, will best inform our understanding of the dynamical mechanisms involved.”

    Comment by Hank Roberts — 24 May 2010 @ 2:16 PM

  444. Heads up: Easterbrook has responded to claims that he faked a graph in his recent Heartland talk… by faking another graph.

    Comment by CTG — 24 May 2010 @ 2:20 PM

  445. http://basicinstructions.squarespace.com/storage/2010-05-23-definition.gif?__SQUARESPACE_CACHEVERSION=1274650961774

    Comment by Hank Roberts — 24 May 2010 @ 3:19 PM

  446. 395, John Mashey, and other related posts: Back in #206, I posted a pointer to a nice presentation on kudzu by Toronto researchers. You don’t need to perform onerous research, like looking in Wikipedia or looking for research papers, that presentation ought to do it, and they actually have better maps. Hopefully, you will read that and return, saying “yes, that is convincing evidence from people who actually study it.”

    A remarkable number of populations have spread dramatically over the same time span:

    tick-borne Lyme disease;
    antibiotic resistant (and indeed MDR and XDR)disease-causing bacteria;
    HIV;
    Africanized honey bees;
    West Nile Virus;
    zebra mussels;
    water hyacinths;
    Dutch Elm disease;
    gypsy moths;
    ice plants;
    Moroccan mustard;
    fire ants;

    and many, many more. Spreading is what invasive species do. Trying to conclude that one in particular out of dozens, maybe thousands, moved an extra 10% of its range because of AGW requires great belief.

    Once you get beyond the fact that CO2 absorbs IR (and then either warms the adjacent atmosphere or re-radiates IR), the rest of AGW theory is flimsy and simple-minded. You have presented what I consider a “simple minded” argument: a particular invasive species has done what all invasive species do, and that is taken as evidence for AGW.

    This is not to deny that Ontario might be warming and that might permit a more rapid spread of kudzu; but kudzu has survived extremely cold winters before, and it will survive this last extremely cold winter.

    Comment by Septic Matthew — 24 May 2010 @ 3:22 PM

  447. “Once you get beyond the fact that CO2 absorbs IR (and then either warms the adjacent atmosphere or re-radiates IR), the rest of AGW theory is flimsy and simple-minded.”

    Do you have anything that states WHY it must be flimsy and simple minded?

    Your assertion seems to be the only flimsy and simple-minded excuse here.

    “This is not to deny that Ontario might be warming”

    No *might* about it.

    It is warming.

    We have the thermometers.

    Comment by Completely Fed Up — 24 May 2010 @ 3:46 PM

  448. Septic Matthew wrote: “Once you get beyond the fact that CO2 absorbs IR … the rest of AGW theory is flimsy and simple-minded.”

    You clearly enjoy making such insulting comments.

    You just as clearly don’t know what you are talking about.

    Comment by SecularAnimist — 24 May 2010 @ 3:49 PM

  449. “CFU, you are asserting the overgeneralization this post tries to address:”

    It’s a generalisation, yes. But NOT an overgeneralsiation.

    If you cannot get the current climate without including AGW, then that shows that every single place is affected that you cannot get right without including anthropogenic CO2e.

    The overgeneralisation is where you are all saying “it only affects global averages, not regional areas”.

    You cannot get a change unless you change the individual events.

    And the promoter of that change is the Sun and the greenhouse gasses.

    The sun shines everywhere.

    The greenhouse gasses mix and appear all over the globe.

    And nothing in your quote addresses your point, nor refutes mine. It is a generalisation, and one that emerges from the requirement to prove the effect and its magnitude.

    I don’t have to prove the effect: the global trend does that.

    And I am not concerning myself with the magnitude.

    Therefore your quote is not germane.

    Comment by Completely Fed Up — 24 May 2010 @ 3:51 PM

  450. “We have two timelines. One is AGW, the other is one where we avoided AGW.”

    In our thought experiment, yes.

    “ach single event occurs in only one of the timelines.”

    No, only in reality and we only have the one reality, the one with AGW. Therefore we are not talking about reality but our thought experiment.

    And there’s no problem there in having each single event happening in BOTH timelines.

    “The AGW timeline will have worse droughts on average,”

    And this is done by increasing the severity of drought that was going to happen anyway and causing droughts that would not otherwise have happened.

    ” but a single drought in AGW time might not even exist in no-AGW time, and vice versa.”

    Nope, the single drought had several causes.

    In one timeline, the cause of energy retention by having a concentration of ~400ppm CO2 happened in only one timeline, but all other variables were the same.

    This sort of “what if something was different” thought experiment is done all the time. The proof of Lorentz time dilation and the argument for the constancy of the speed of light for all observers in any inertial frame, even very different ones are both made by changing only one thing.

    Comment by Completely Fed Up — 24 May 2010 @ 3:56 PM

  451. “Spreading is what invasive species do.”

    But why hadn’t they spread into those areas before? It’s not like they were only created a year ago.

    Comment by Completely Fed Up — 24 May 2010 @ 3:58 PM

  452. Septic Matthew@446,
    There is no AGW theory. There is a theory of Earth’s climate that explains the bulk of evidence going back hundreds of millions of years, that illuminates the dynamics of current climate and that is both self-consistent and based on basic physics. It is an unfortunate, but inevitable consequence of this theory that the 38% increase in atmospheric CO2 is bound to raise temperatures by roughly 3 degrees per doubling.

    If you want to understand the science, forget about “AGW theory”. It is a straw man constructed by denialists. Learn the theory of Earth’s climate and you will see why it is so successful and why the overwhelming majority of scientists are convinced beyond doubt of the reality of anthropogenic causation of the current warming epoch. Doing anything less is just pudknocking.

    Comment by Ray Ladbury — 24 May 2010 @ 4:03 PM

  453. Septic Matthew says …

    and many, many more. Spreading is what invasive species do. Trying to conclude that one in particular out of dozens, maybe thousands, moved an extra 10% of its range because of AGW requires great belief.

    Or knowledge of plant physiology (since kudzu is a plant).

    Invasive species frequently become extremely expensive pests, and as such become among the most heavily-studied species on the planet.

    The same is true of kudzu. It’s known the northern range of this species in the eastern US is temperature-limited. It’s not a guess.

    On the other hand … you’re guessing. Which requires “great belief”, faith in your guess, or faith in the professionals who’ve studied this species and have determined their ecological needs?

    Comment by dhogaza — 24 May 2010 @ 4:47 PM

  454. SepticMatthew has done better in the past. This is some kind of regression, or unveiling. Only he can say.

    Comment by Doug Bostrom — 24 May 2010 @ 5:02 PM

  455. Ray Ladbury wrote: “… the overwhelming majority of scientists are convinced beyond doubt of the reality of anthropogenic causation of the current warming epoch.”

    To which the predictable “septical” response is: sure, anthropogenic causation is a reality — but the overwhelming majority of scientists are not convinced beyond doubt that the worst imaginable outcomes of AGW are certain to occur, therefore there is no reason to do anything about it (e.g. anything that would diminish ExxonMobil’s one hundred million dollars per day in profit).

    Comment by SecularAnimist — 24 May 2010 @ 5:04 PM

  456. CFU,

    This began with a comment by Frank Giger way back at #73, which launched a discussion about whether one could say the drought was caused by GW or not. At #93, the Seager paper was brought up. At #97 you came in asking: “Can you say it would have been as bad if it weren’t warming?” Before long (#147), you were taking Frank to task for failing to remember that the discussion had really been about your question all along.

    So I’ll concede your #428. You have indeed consistently talked about man-made warming making drought worse (= making stuff drier). As if that were somehow quite different from causing drought (= making stuff too dry). And yet, at the same time, as if it were a trenchant rebuttal to those saying man-made warming had not been shown to cause the drought.

    I admit I never really got the distinction.

    > When a position is logical, it’s hard NOT to use an argument that shows
    > the illogical extreme.

    I think that’s my cue to sink back, exhausted, onto the cartons of yoghurt.

    Comment by CM — 24 May 2010 @ 5:12 PM

  457. From Tamino a couple of years ago:

    http://tamino.wordpress.com/2008/05/30/drought-in-australia/

    Comment by Jacob Mack — 24 May 2010 @ 5:38 PM

  458. Also of interest:

    http://news.bbc.co.uk/2/hi/science/nature/3191174.stm

    http://www.springerlink.com/content/j7188j6389327284/

    Comment by Jacob Mack — 24 May 2010 @ 5:52 PM

  459. Enough of the references I found:

    http://assets.panda.org/downloads/wwf2002drought_ut3s.pdf

    Ofcourse I would like to see more stats methods. Do you have stat references CFU?

    Comment by Jacob Mack — 24 May 2010 @ 6:01 PM

  460. It seems that insolution was furthest south about 2000 years ago (minimum of orbitl forcing in the far north). It also seems that norhern hemisphere temperatures have been declining, on average, over those same two millennia; see the hockeystick but also other resconstructions, as illustrated by
    http://en.wikipedia.org/wiki/File:Holocene_Temperature_Variations.png
    What about the nest two millennia under the (alternate universe) assumption of no substantial anthropogenic influences? Would temperatures be going (slowly) up anyway? Further down due to longer phase lag to the orbital forcing?

    Crucifix & Rougier (2009), Figure 9, suggests that, on avaerage, temperatures would continue to climb for about 10 ky in that alternate universe. This suggests that phase lag isn’t overly large given that orbital forcing is not increasing and will do so for about 10 ky. So possibly even without excess CO2 temperatures now would be slowly increasing and continue to do so. That would mean a phase lag of almost 2 ky and as we will eventually see that has some profound consequences for various conceptual models of long term climate.

    But first, lets see if we can find a (linear) trend in the instrumental record. Tol, R.S.J. and A.F. de Vos (1998), ‘A Bayesian Statistical Analysis of the Enhanced Greenhouse Effect’, Climatic Change, 38, 87-112, determine one, much less important than increasing CO2 concentrations. I modified
    http://www.realclimate.org/index.php/archives/2010/03/unforced-variations-3/comment-page-12/#comment-168530
    to include a linear trend over the 13 decades of the GISTEMP instrument based global temperature product. The best fitting trend is but 0.063K/Century so most of the observed increase is attributed to CO2; moreover the fit is essentially no better than the simplier model linked above and parsimony, in the form of AIC, recommends the simplier model. But for our current purposes, neither Tol & de Vos nor I find a negative trend which suggests that the long term trend would indeed be upwards in the alternate universe.

    This is very far from the so-called hockeystick. The presumed uptrend in this alternate universe is of about the same size, or less, than the downtrend seen in the initial portion of the hockeystick. Clearly something extraordinary, excess CO2 in superabundance, explains the blade uptrend of the hockey stick; not the issue here.

    Attempting to explain the consequences (for long term models) of such a short pahse lag, only around 2 ky, will require some formulas and is best done in a separate comment after a bit more thought about it.

    Comment by David B. Benson — 24 May 2010 @ 6:07 PM

  461. I previsously posted about at least three different long term climate conceptual models; two of these use modes, Paillard uses three modes and Tziperman et al. use but two. Assume 2 or 3 modes but we are currently in the interglacial mode so we only have the linear differential equation part to consider. Both of those papers appear to have a characteristic time of about 1/a = 20 ky, so we will use that, for now, with time units of 1 ky. I’ll simplify to use around 20 ky for the precession period and around 40 ky for the obliquity period in the orbital forcings; being precise about these values is not required.

    While all those papers treat ice volume as the variable, here I will use temperature instead, and rather crudely assume that high temperature is linear proportion to lower ice volume. I want to, once again, introduce Laplace transforms (s-plane) as more convenient for linear system analysis. So the temperature is denoted by the pair
    (Y(s), y(t))
    following the convention that the transform is given on the left and the corresponding time domain function is given on the right. The raditive orbital forcing, the input, is denoted
    (R(s),r(t))
    and the system transfer function by
    (W(s),w(t))
    where
    Y(s) = W(s)R(s)
    and then we simply look up the time domain answer, y(t), in a table of Laplace transform — function paris.

    The linear system models of the two papers mentioned are of the form W(s) = 1/(s+a) thought of as a reservoir (of ice) which relaxes along a decaying expotential exp(-at) to an equilibrium value when perturbed by a unit impulse input R(s) = 1. Then for sinusoidal input R(s) = 1/(s^2+k^2) the temperature varies as a sinusoidal of the same frequency at a phase lag given by
    arctan(k/a).
    For the response to obliquity we then have
    arctan(2.pi(1/40)/(1/20)) = arctan(pi) ~ 72 arcdegrees being around 7 ky of lag
    while for precession
    arctan(2.pi(1/20)/(1/20)) = arctan(2.pi) = 81 arcdegrees being around 4 ky of lag. Both, from my previous comment, seem far too long.

    That probably makes little difference for the analysis done in the published papers but simply doesn’t agree with those analyses, mentioned in the prior post, which certainly indicate a phase lag of at most 3 ky. Something is missing, except in Crucifix & Rougier (2009); carbon dioxide.

    So we need a system transfer function which explicitly includes the positive feedback induced by CO2 (+ water vapor + clouds + …). This must wait until tomorrow.

    Comment by David B. Benson — 24 May 2010 @ 8:02 PM

  462. David, I must say I have been enjoying your posts as o late.

    Comment by Jacob Mack — 24 May 2010 @ 11:16 PM

  463. Ray Ladbury (435), I am overwhelmed and somewhat shocked.

    If you plot a graph of CO2 concentration along the X-axis and forcing in W/m^2 along the Y-axis you get a curve. (That’s Algebra-1, btw.) That curve has a slope, though probably variable depending on the scale. That slope is called the differential of the function. (Some may prefer “derivative”.) In case I’m going too fast — That slope is called the differential. It measures the rate of change of forcing against the changing concentration. At certain X values, that’s what I claimed is not completely known.

    What’s Happer got to do with it?!?!

    All of that other crap you accuse me of saying or implying is, well, crap.

    Comment by Rod B — 24 May 2010 @ 11:25 PM

  464. Septic only dissenters like Lindzen refers to it as “AGW theory.”

    Also an interesting read in regards to regional precipitation:

    Extremes (2010) 13:219–239
    DOI 10.1007/s10687-009-0098-2
    A comparison study of extreme precipitation
    from six different regional climate models
    via spatial hierarchical modeling
    Erin M. Schliep ·Daniel Cooley·Stephan R. Sain ·
    Jennifer A. Hoeting.

    Abstract:

    “We analyze output from six regional climate models (RCMs) via a spatial
    Bayesian hierarchical model. The primary advantage of this approach is that the statistical
    model naturally borrows strength across locations via a spatial model on the
    parameters of the generalized extreme value distribution. This is especially important
    in this application as the RCM output we analyze have extensive spatial coverage, but
    have a relatively short temporal record for characterizing extreme behavior. The hierarchical
    model we employ is also designed to be computationally efficient as we
    analyze RCM output for nearly 12000 locations. The aim of this analysis is to compare
    the extreme precipitation as generated by these RCMs. Our results show that,
    although the RCMs produce similar spatial patterns for the 100-year return level,
    their characterizations of extreme precipitation are quite different. Additionally, we
    examine the spatial behavior of the extreme value index and find differing spatial
    patterns for the point estimates for the RCMs. However, these differences may not be
    significant given the uncertainty associated with estimating this parameter.”

    Extremes (2010) 13:205–217
    DOI 10.1007/s10687-010-0105-7
    Sources of uncertainty in the extreme value statistics
    of climate data
    Michael Wehner
    Received: 1 April 2009 / Revised: 27 January 2010 /
    Accepted: 11 February 2010 / Published online: 25 February 2010
    c The Author(s) 2010. This article is published with open access at Springerlink.com

    Abstract:

    “We investigate three sources of uncertainty in the calculation of extreme
    value statistics for observed and modeled climate data. Inter-model differences in
    formulation, unforced internal variability and choice of statistical model all contribute
    to uncertainty. Using fits to the GEV distribution to obtain 20 year return
    values, we quantify these uncertainties for the annual maximum daily mean surface
    air temperatures of pre-industrial control runs from 15 climate models in the CMIP3
    dataset.
    Keywords Extreme temperature · Return value · Uncertainty · Climate models
    AMS 2000 Subject Classification 62G32.”

    I would give the links, but these come from my University Pro-quest account. Not too difficult to get the whole of the publications with University access or a Springer link account, but if You cannot, I can cut and paste the results if requested.

    These are heavily statistically based as is necessary for this subject matter.

    Comment by Jacob Mack — 25 May 2010 @ 12:57 AM

  465. And finally:

    “Climate changenext term impacts on previous termcrop yield, cropnext term water productivity and food security – A review

    Alert
    This article is not included in your organization’s subscription. However, you may be able to access this article under your organization’s agreement with Elsevier.

    Yinhong Kanga, Shahbaz Khanb, Corresponding Author Contact Information, E-mail The Corresponding Author and Xiaoyi Maa

    aDepartment of Water Resources and Architectural Engineering, Northwest A&F University, Yangling 712100, China

    bDivision of Water Sciences, UNESCO, 1 Rue Miollis, 75 732 Paris Cedex 15, SP, France
    Received 20 May 2009;
    revised 8 August 2009;
    accepted 14 August 2009.
    Available online 31 October 2009.

    Abstract

    This paper provides a comprehensive review of literature related to the assessment of previous term climate change next term impacts on previous term crop next term productivity using previous term climate,next term water and previous term crop yield next term models. The existing studies present that previous term climate change next term models with higher spatial resolution can be a way forward for future previous term climate next term projections. Meanwhile, stochastic projections of more than one previous term climate next term model are necessary for providing insights into model uncertainties as well as to develop risk management strategies. It is projected that water availability will previous term increase next term in some parts of the world, which will have its own effect on water use efficiency and water allocation. previous term Crop next term production can previous term increase next term if irrigated areas are expanded or irrigation is intensified, but these may previous term increase next term the rate of environmental degradation. Since previous term climate change next term impacts on soil water balance will lead to previous term changesnext term of soil evaporation and plant transpiration, consequently, the previous term crop next term growth period may shorten in the future impacting on water productivity. previous termCrop yieldsnext term affected by previous termclimate changenext term are projected to be different in various areas, in some areas previous term crop yields next term will previous term increase,next term and for other areas it will decrease depending on the latitude of the area and irrigation application. Existing modeling results show that an previous term increase next term in precipitation will previous term increase crop yield,next term and what is more, previous term crop yield next term is more sensitive to the precipitation than temperature. If water availability is reduced in the future, soils of high water holding capacity will be better to reduce the impact of drought while maintaining previous term crop yield.next term With the temperature increasing and precipitation fluctuations, water availability and previous term crop next term production are likely to decrease in the future. If the irrigated areas are expanded, the total previous term crop next term production will previous term increase;next term however, food and environmental quality may degrade.

    Keywords: previous term Climate change next term impacts; previous term Crop yield next term; Food security; Water productivity; Water use efficiency.”

    Progress in Natural Science
    Volume 19, Issue 12, 10 December 2009, Pages 1665-1674.

    The points of all of this is simple: the issue is complex. I do not know for certain any specific drought and its duration or extent in relation to AGW though I certainly know some of these droughts must be made worse by AGW in duration and extent in time. I also know that flooding can and IS made worse by AGW though I cannot say with certainty which ones precisely or to what extent.

    Prior soil conditions as pointed out by Luke on The Tamino link I provided affects sensitivity, as does irrigation access and methods as pointed out the last set of references I quoted.

    Floods in an arid drought ridden demographic is NOT a good thing either, as they can rob soil of necessary nutrients, destroy crops and other plant life, and contaminate drinking water supplies.

    Some drought prone regions Do and will end up cooling a bit due to climate change, but that is not necessarily always a good thing either. Although some crops have, do and will grow faster due to elevated C02 and temperatures, the limiting of nitrate conversion to protein is one issue, and another in the articles I posted is what precipitation conditions were present prior to the regional temperature changes in question.

    Droughts are difficult to analyze in the long term in my humble opinion. Historically there are some really long, killer droughts prior to the 20th century in susceptible areas. This does NOT mean that AGW is not contributing such occurrences now, nor is AGW not a serious matter.

    What IS clear is as good as GCM’s have become, as talented and hard working the climatologists are, (for the most part, minus the “usual suspects, in the RC vernacular)as much as the majority of the IPCC report is valid and reliable, and as much about the physics we do know, there are quite significant uncertainties in the descriptive data, inferential statistical analysis, and thus prediction methods.

    I do not want to have to say this last thing again: I do NOT deny that we must face potential serious consequences of AGW as well as CURRENT issues as well. What I do not like is when one aspect is hyper focused on at the exclusion of other major concerns or an individual claims certainty in a particular claim than there is.

    I also appreciate RC’s patience overall in these heated discussions.

    I have also found Michael Mann’s papers of great benefit too.

    Comment by Jacob Mack — 25 May 2010 @ 1:34 AM

  466. Jacob, that one was easy: it was statistically anomalous. Rather like the heatwave in 2003 in Europe.

    But practically every drought was made worse by AGW, even if they don’t seem to be out of the ordinary.

    After all, the warming didn’t know that the Australian drought “needed” to be so deep and concentrate all its’ changes into that one event.

    If you go waaaay back, you’ll see my explanation of a 4% increase in severity of an event that has a random attribution of severity and how you’d need ~400 events to show that it was increasing by 4%.

    SEUS drought was one of those 400.

    You cannot show this by statistical analysis, but you can infer it from modelling by leaving out ~1/4 of the CO2 and running a hindcast model over and over again.

    Nobody has ever done that as far as I know and published the results, though the test was done to show that anthropogenic changes had to be included to make a climate that reflects the current one.

    And the point is that AGW is costing us every time there’s something that can be exacerbated by warming temperatures. Not just the big events, even the little ones.

    Comment by Completely Fed Up — 25 May 2010 @ 2:30 AM

  467. “I admit I never really got the distinction.”

    That was my frustration: I knew you weren’t getting that and that once you did, you’d either come up with a wrinkle that I hadn’t considered, or accepted and modified my proposition to fit in with what you knew.

    Heck, maybe someone out there would have shown that the coastal extreme of that event was actually made less severe because of increased evaporation from the nearby coast (with wind patterns to show this).

    It’s not a particularly difficult concept, but so many people were arguing what they thought I meant and didn’t change their assumption.

    Quite annoying.

    Comment by Completely Fed Up — 25 May 2010 @ 2:35 AM

  468. “This began with a comment by Frank Giger way back at #73, ”

    And frank also turned it from the specific case (that event) into the generic which then led to everyone not getting my point.

    And Frank also going “you can’t EVER attribute one single event to AGW, that is SO WRONG” which you then seemed to be picking up.

    Which he was hoping would happen by morphing the statement from the specific to the general. Notice that he’s kept silent recently.

    Comment by Completely Fed Up — 25 May 2010 @ 2:38 AM

  469. “What I do not like is when one aspect is hyper focused on at the exclusion of other major concerns or an individual claims certainty in a particular claim than there is.”

    Who is doing that?

    I’m focusing on the discussion on one thing, other people are focusing on other things.

    Comment by Completely Fed Up — 25 May 2010 @ 7:35 AM

  470. Rod B.,
    Precision is important. So is ensuring that your language affects the physics. Your posts have been so vague that it isn’t even possible to say whether they are right or wrong. That is worse than being wrong! Wrong can be corrected. Bullshit can’t. We know CO2 sensitivity quite well. We know it is very unlikely to be above 4.5 degrees per doubling and extremely unlikely to be below 2 degrees per doubling. That is a pretty tight constraint.
    There are many things we don’t understand about climate. They do not invalidate what we do understand.

    Comment by Ray Ladbury — 25 May 2010 @ 10:38 AM

  471. Bill Ruddimann (#365),
    I’m generally wary of arguments which pit “natural” against “anthropogenic”. It’s philosophically unsound and your argument reads as an “excluded middle” fallacy.
    Sensitivity is a convenient abstraction which is not going to apply equally in all contexts, especially not if the variations in global temperature under examination are small to begin with. Is it not conceivable that the kind of regional climate changes hypothesized in Mike’s orginal post are going to have an impact on the carbon cycle quite aside from any impact on the global temperature average? Increased rainfall on arid regions adjacent to forests could promote tree growth for instance. Such a conjecture does not imply that you are wrong of course, only that your carbon cycle sensitivity argument is insufficient. I for one am interested to read more about the research reagarding any impact the genocide of native Americans might have had on the climate.

    Comment by Anonymous Coward — 25 May 2010 @ 10:56 AM

  472. [edit - for once can people argue about something interesting rather than picking over pointless semantic confusions?]

    Comment by Completely Fed Up — 25 May 2010 @ 11:13 AM

  473. “It measures the rate of change of forcing against the changing concentration. At certain X values, that’s what I claimed is not completely known.”

    Where did you say “the rate of change of forcing … is not completely known”???

    “the forcing equation for CO2 as it goes from say 350ppm to 700ppm because of anthropogenic emissions has never been observed”

    Doesn’t say that.

    Neither does “My assertions of the “less than irrefutable” are based on the degree or the differential of the functions.”

    Nor “theoretically if CO2 did absorb all of the radiation in its absorption band, then no matter how much CO2 was at higher altitudes it would have no radiation to absorb”

    So where did you say “it is not completely known”? And what is “it”? CO2/temperature sensitivity?

    We wait with baited breath…

    Comment by Completely Fed Up — 25 May 2010 @ 11:41 AM

  474. PPS wasn’t another poster pissed off at how there was concentration on one topic? Well when I try, what happens? [edits], that’s what.

    [cry us a river. edits occur because you're continually engaging in pointless, self-defensive bickering and/or insulting others. be happy anything gets through and get over yourself.]

    Comment by Completely Fed Up — 25 May 2010 @ 11:43 AM

  475. At any rate most of is agree we should continue to lower GHG gases, preserve more forests, plant more trees, save dying out animal species, and in the meantime adopt technology that helps us adapt to the changing climate… yes? Maybe we should concentrate on where we agree and discuss what might be done about slowing the increasing GHG emissions and conserving natural habitats/crops. I mean this specifically in relation to those regions most heavily affected by weather extremes and climate induced damage, whatever the synergy of causes.

    Comment by Jacob Mack — 25 May 2010 @ 12:16 PM

  476. > baited breath

    http://karenspoetryspot.blogspot.com/2008/01/cruel-clever-cat-by-geoffrey-taylor.html

    Comment by Hank Roberts — 25 May 2010 @ 12:53 PM

  477. 476: I always thought that meant you were waiting with a worm on your tongue.

    Comment by John E. Pearson — 25 May 2010 @ 2:24 PM

  478. #463 Rod B (Black was it?)

    I have to join Ray in his concern. In many ways, it is safe to say, ambiguity is the root of all evil. Especially true in science.

    Your continued habit of not including the constraints and the relative certainty associated with the values in your considerations, devalues your opinion/perspective.

    In other words your continuing to be play in the noise while ignoring the signal does not make your opinion look intelligent, in fact quite the opposite.

    This translates to your presented lack of relevant contextual reasoning on the issue as wholly or largely inadequate.

    Plus, I’m not a maths guy, but I trust Ray a hell of a lot more than you on these subjects. Your track record has not exactly been a shining example of reasonability, in my opinion.


    A Climate Minute The Greenhouse EffectHistory of Climate ScienceArctic Ice Melt

    ‘Fee & Dividend’ Our best chance for a better future – climatelobby.com
    Learn the Issue & Sign the Petition

    Comment by John P. Reisman (OSS Foundation) — 25 May 2010 @ 3:07 PM

  479. Ah, CFU:

    “And Frank also going “you can’t EVER attribute one single event to AGW, that is SO WRONG” which you then seemed to be picking up.

    Which he was hoping would happen by morphing the statement from the specific to the general. Notice that he’s kept silent recently.”

    One can’t say any one weather event is proof (positive or negative) of AGW. Period. Weather happens.

    Today was well within seasonal norms for my area. Is this a result of AGW? How? Was it supposed to rain today if not for AGW? Prove it.

    What you miss, CFU, is that I’m not saying climate change isn’t happening, or that we’re influencing it.

    My point – which stands – is that it does little service to anyone to point at particular weather events (including very short term ones over several months) as proof or disproof of climate change. Credibility goes out of the window.

    I’ve pretty much bailed from this thread because you’re just all worked up and obstinantly refusing to actually comprehend what’s being written.

    Comment by Frank Giger — 25 May 2010 @ 4:07 PM

  480. So far we have taken the system transfer function response to orbital forcing R(s) to be due to slow changes in an ice reservoir. But suppose the relaxation is fast, on the order of the deep ocean characteristic time so that a = 1 ky^(1-). Then the phase lag for obliquity is only
    arctan(2.pi/40) ~ 9 arcdegrees so around 1 ky of phase lag
    and for precession but
    arctan(2.pi/20) ~ 12 arcdegrees being a phase lag of 0.667 ky.
    Perhaps these are too small as we seem to have closer to 2 ky of phase lag to the recent minimum in r(t).

    Whatever seems an appropriate characteristic time for the temperature response to r(t) we still ought to take the positive feedback due to CO2 into account. As is well understood this is nonlinear in the concentration but as the variations in concentrations we need to consider are small, a linear approximation is adequate for starters anyway. These variations are small because we are only considering nonanthropogenic variations over an interglacial, the Holocene. So the minimum is maybe as low as 260 ppm and from Crucifix & Rougeier (2009) a absolute maximum of 310 ppm certainly suffices. We’ll just rough in a linear approximation over this range.

    We take the ocean as the CO2 reservoir so the feedbak factor is
    H(s) = h/(s+b)
    with b (for now) being 1 ky^(-1). The forward gain we alredy have considered but now write as
    G(s) = 1/(s+a).
    With positive feedback the system transfer function is now

    W(s) = G(s)/(1 – G(s)H(s))

    and using the auxiliary variables
    c = (a+b)/2
    d^2 = h – ab + c^2
    one rearranges the transfer function as

    W(s) = (s+b)/[(s+c)^2 + d^2]

    and noting that the inverse Laplace transform of 1/[(s+c)^2+d^2] is
    (1/d)exp(-at)sinh(bt)
    proceed to find the inverse Laplace transform of W(s). Before (or after) doing so, note that h, the feedback constant, is bounded above by ab for stability. We have some reason to think it is about half that maximum value, so hereinafter we use
    h = (1/2)ab.

    Irrespective of the value chosen for h, the inverse Laplace transform of W(s) is

    W(t) = (1/2d)[(b-c+d)exp(-(c-d)t) + (c+d-b)exp(-(c+d)t)]

    which can be thought of as the relaxation of two reservoirs, one with characteristic time 1/(c-d) and the other with characteristic time 1/(c+d). This came as quite a surprise to me. (I’ve never considered such a complicated system with positive feedback before.) By its very form it has some rather amazing properties as a, b (and h) are varied. In particular, if c-d is small the left term has a very long characteristic time; one way to make it small is to increase h towards the maximum. This shows that the positive feedback is prolonging the response to a unit impulse function; similarly in response to a sinusoid the phase lag as close to pi/2. For example with a = 1/40 and b = 1 we have
    W(t) = 0.969exp(-0.019t) + 0.031exp(-1.031t)
    and so the dominant term has a characteristic time of about 53 ky!

    So adding in the postive feedback of CO2 just mad the pahse lag even worse, although it is certainly proper to include. All the clues should now be in place and in my next comment I’ll explain a solution altough I do hope you’ll work it out for yourself in the nonce.

    Comment by David B. Benson — 25 May 2010 @ 5:06 PM

  481. Correction: the inverse Laplace transform of 1/[(s+c)^2+d^2] is
    (1/d)exp(-ct)sinh(dt)

    Comment by David B. Benson — 25 May 2010 @ 5:09 PM

  482. Another correction, apologies to all.

    For example with a = 1/20 and b = 1 we have
    W(t) = 0.969exp(-0.019t) + 0.031exp(-1.031t)
    and so the dominant term has a characteristic time of about 53 ky!

    Comment by David B. Benson — 25 May 2010 @ 5:12 PM

  483. Rod B saays: “if you plot a graph of CO2 concentration along the X-axis and forcing in W/m^2 along the Y-axis you get a curve. (That’s Algebra-1, btw.)”

    I’m beginning to understand your difficulties. The fact that such a plot produces a curve is not algebra. It is physics. Nothing in all of mathematics implies that the forcing is a single valued function of [CO2]. The fact that one obtains a curve rather than a random cloud of points is a consequence of physics, not mathematics.

    Comment by John E. Pearson — 25 May 2010 @ 5:28 PM

  484. For 1/a the characteristic response time of ice to the orbital forcing, r(t), and 1/b the characteristic time for CO2 to respond to temperature, we are assuming that temperature goes up as ice wanes and vice versa. The values of a and b have to be estimated by some means, but irrespective of the values using the auxiliary variables
    c = (a+b)/2
    d^2 = h – ab + c^2
    we the system transfer function
    W(t) = (1/2d)[(b-c+d)exp(-(c-d)t) + (c+d-b)exp(-(c+d)t)]
    in which we set the feedback constant h to h = (1/2)ab, i.e., half maximum as determined from other studies.

    We have seen that using 1/a on the order of tens of kiloyears (with b=l) eads to impossibly long lag times. So lets try 1/a = 1 ky (with b=1) as the ice characteristic time during an interglacial (this might be different after a mode switch). Then

    W(t) = 0.5exp(-0.5t) + 0.5exp(-1.707t)

    so the left term has a characteristic time of 2 ky while the right term’s characteristic time is 0.586 ky. These seem about right. For obliquity forcing, r(t) = sin(wt) with w = 2.pi/40, we have for the left term a pahse lag of p_l = 17.5(2.pi/360) radians and for the right term p_r = 5.5(2.pi/360) radians in

    W(t) ~ sin(wt – p_l) + sin(wt – p_r)

    which is a sine wave with a phase lag of about 1.3 ky, close enough to see that setting 1/a to about 2 ky (with b = 1) ought to do it.

    We can simplify by ignoring CO2 to just use W(s) = 1/(s+a) = 1/(s+1/3) to obtain an obliquity phase lag of about 1.7 ky and a precession phase lag of about 2.4 ky.

    I take all this to demonstrate that the characteristic time for ice volume response to orbital forcing during an interglacial to be around 1–3 ky, being in better accord with the past two millennia than the much longer characteristic times used in the long range climate conceptual models I have read about.

    Something else learned from studying the past millenia or so.

    Comment by David B. Benson — 25 May 2010 @ 7:44 PM

  485. Rod B sir please, you are just embarrassing yourself.

    Comment by Jacob Mack — 25 May 2010 @ 8:27 PM

  486. Looks like business as usual really steepens the emissions curve.

    Global CO2 emissions to jump 43% by 2035 — EIA
    http://www.eenews.net/eenewspm/2010/05/25/5/
    (05/25/2010) (subscription)
    Katherine Ling, E&E reporter

    Energy-related carbon dioxide emissions will rise 43 percent worldwide by 2035 under current policies, the U.S. Energy Information Administration said in an analysis released today.

    Emissions will rise from 29.7 billion metric tons in 2007 to 42.4 billion metric tons in 2035, says the report summary, the first effort by EIA to forecast emissions till 2035. The agency will release the full report later this year.

    Growing economies and populations will drive emission increases, with world energy consumption expected to increase 49 percent from 2007 to 2035, EIA said.

    Developing countries are projected to increase energy demand by 84 percent and double their share of the world’s carbon emissions, contributing two-thirds of the global total by 2035, EIA said. Developed countries’ energy consumption will expand 14 percent while they maintain levels of carbon emissions, the agency said. Industrialized countries’ emissions made up about half the world’s total in 2007 but are expected to represent a third of global emissions in 2035.

    Fossil fuels will meet more than 75 percent of total energy needs in 2035, EIA said. World oil production will increase to 110.6 million barrels per day and reach $133 per barrel in 2035, under the agency’s reference case.

    But oil will make up 30 percent of world energy consumption in 2035, compared to 35 percent in 2007, the agency said. It is also about 10 percent less than what EIA had predicted about five years ago, Guy Caruso, senior adviser at Center for Strategic & International Studies and former EIA administrator, said at a press conference in Washington, D.C.

    EIA’s high oil-price scenario reaches $210 per barrel in 2035 — accounting for possible lower production from key exporters — and the low oil-price scenario stays around $51 per barrel.

    The natural gas industry needs to increase production in 2035 by 46 percent to meet the projected growth in demand, but EIA predicts “well supplied” markets will keep prices down.

    Howard Gruenspecht, deputy EIA administrator, said he expects oil prices to remain about three times higher than gas prices in North America because of shale gas, tight gas and coalbed methane supply in the United States and Canada.

    Global coal consumption is projected to continue rising, especially in China, growing at an average annual rate of 1.6 percent, the report says. Coal will still account for 43 percent of the world’s electric generation by 2035, EIA said.

    The report cites “improved prospects” for nuclear power, backed by policy changes in Europe and overall higher capacity utilization rates — on top of more than 8 percent growth per year in new power plants in China and India. EIA’s forecast for nuclear generation in 2030 is 9 percent higher than last year’s projections and reaches a total of 4.5 trillion kilowatt-hours in 2035. But nuclear still decreases its supply in the overall global electricity portfolio, accounting for 14 percent in 2007 and 13 percent in 2035, the report says.

    EIA forecasts renewable energy as the fastest-growing source of world power supply, “but from a relatively small base,” growing from 10 percent to 14 percent of supplies. Renewables will make up 23 percent of electricity supply in 2035 but with 80 percent of that coming from hydropower and wind power.

    “Except for those two sources, most renewable generation technologies are not economically competitive with fossil fuels over the projection period,” the report says.

    Asked how to square EIA’s forecast with the goal of some scientists and environmentalists for cutting greenhouse gas emissions 80 percent by 2050, Gruenspecht replied, “Policymakers have a lot of work to do.”

    Comment by Tim Jones — 25 May 2010 @ 8:40 PM

  487. 452 Ray Ladbury: There is no AGW theory.

    If you insist. I’ll try to call it AGW for short.

    To me it is at least as theoretical as General Relativity or the Krebs Cycle, each of which is a part of a larger system.

    Comment by Septic Matthew — 25 May 2010 @ 9:57 PM

  488. 453, dhogaza:The same is true of kudzu. It’s known the northern range of this species in the eastern US is temperature-limited. It’s not a guess.

    That’s only “known” if species are immutable. When species experience random variation, their extents are not limited by physics. It is not a guess that SIV is limited to a subset of Africa, yet since the 1930s (or maybe since the 1950s), its variant HIV has spread worldwide.

    Comment by Septic Matthew — 25 May 2010 @ 10:02 PM

  489. Ray Ladbury (470), I simply and clearly (I thought) said one of my biggest areas of skepticism is the forcing math and physics of the doubling of CO2 in the domain of 350ppm to 700ppm or at some higher doubling values. What is vague about that? Is this not precise enough for you? How about 396ppm to 792ppm?? What is bullshit about this? (You claim my physics/math assertion is not correct but that’s not what you were calling bullshit.)

    Comment by Rod B — 25 May 2010 @ 10:45 PM

  490. PS on reflection the blame ought to be distributed ; maybe my point wasn’t originally as clearly stated in this thread as I thought. Though it had been before (to wit my broken record comment); maybe I assumed too much.

    Still, the non-understanding of “differential” is astounding to me. But, what the hey. It’s the kind of debate that the moderators would prefer die.

    Comment by Rod B — 25 May 2010 @ 11:14 PM

  491. CFU #466, let me get this straight: We’ve been going in circles for eight pages or so over whether AGW is making an as yet *undetectable* contribution to worse droughts? Good grief.

    Comment by CM — 26 May 2010 @ 2:12 AM

  492. “One can’t say any one weather event is proof (positive or negative) of AGW. Period. Weather happens.”

    Indeed it does. And so is winning the 100m by a whole second. It’s not PROOF they’ve cheated.

    You never answered me in #175, did you.

    “What you miss, CFU, is that I’m not saying climate change isn’t happening, or that we’re influencing it.”

    What you miss is that if we’re not changing any single event, we cannot change the climate. Your position is completely untenable.

    “My point…is that it does little service to anyone to point at particular weather events … as proof or disproof of climate change. Credibility goes out the window”

    Good job I’ve never said that. Neither has anyone else except to strawman a “You’re wrong” out of it.

    You never answered #175 and you’ve never explained how we can change the climate without changing every event.

    You bailed because you couldn’t answer #175 and you are unable to accept that there is change even in a single event because without changing the single events you don’t change the trend.

    Is this because you want to continue to say that AGW *will* be a problem, just isn’t one now?

    Comment by Completelye Fed Up — 26 May 2010 @ 2:33 AM

  493. Rod 463,

    A differential is NOT the same as a derivative. You need to reread a calculus textbook.

    Comment by Barton Paul Levenson — 26 May 2010 @ 5:49 AM

  494. David,

    I feel your pain. For long expositions on technical subjects, I’ve started to write them out in a text editor first, and check them over, before posting to RC. But it’s still easy to click “Say It!” and get some asinine error in there…

    Comment by Barton Paul Levenson — 26 May 2010 @ 5:55 AM

  495. #488–Sorry, Matthew, your appeal to genetic variation or change is a fail, and you’d have known that if you’d read the links posted.

    It is known that kudu is temperature limited, since the researchers actually measured tissue damage at various (cold) temperatures, using different populations of kudzu from different areas. There’s basically no reproduction for kudzu chilled to -20C for 4 hours. The data on geographic spread are consistent with that -20C thermocline.

    They didn’t just guess.

    Comment by Kevin McKinney — 26 May 2010 @ 7:45 AM

  496. “A differential is NOT the same as a derivative.”

    I called the Humpty-Dumpty defence right, didn’t I.

    Maybe an intern is posting for Rod B.

    Comment by Completely Fed Up — 26 May 2010 @ 8:03 AM

  497. “We’ve been going in circles for eight pages or so over whether AGW is making an as yet *undetectable* contribution to worse droughts”

    No, YOU have been arguing that I’ve said that we can attribute a drought to AGW.

    I’ve been arguing I haven’t been arguing that and restating what I *have* been arguing until I find the shape of words that fits in your head.

    And it is a detectable contribution. It just isn’t utile as a statistical proof of the strength of climate change on its own because nobody has done the work yet to see what the inputs are for that weather event.

    That you continue to get my argument wrong is a sheesh moment.

    Comment by Completely Fed Up — 26 May 2010 @ 8:06 AM

  498. “We’ve been going in circles for eight pages or so over whether AGW is making an as yet *undetectable* contribution to worse droughts”

    No, YOU have been arguing that I’ve said that we can attribute a drought to AGW.

    I’ve been arguing I haven’t been arguing that and restating what I *have* been arguing until I find the shape of words that fits in your head.

    And it is a detectable contribution. It just isn’t utile as a statistical proof of the strength of climate change on its own because nobody has done the work yet to see what the inputs are for that weather event.

    And that you make that unsupported statement (2W/m2 IS detectable as an energy source) is why we’ve spent 8 pages.

    Comment by Completely Fed Up — 26 May 2010 @ 8:09 AM

  499. Like Frank, I’ve pretty much bailed on the “drought debate” as unproductive. However, here’s what I’m hearing:

    CFU: every weather event must logically be affected by AGW. Specifically, every drought event must logically be worsened.

    (My thought, FWIW: This can’t be refuted as possibly true, yet it seems to rest on an unproven assumption that AGW is effective *always* and *everywhere*–an assumption dubious in light of the fact that to date, at least, there are still places that don’t (yet) show a warming trend. Of course, they might have been cooler still in the (hypothetical) no-AGW case, but the point is we don’t know. Hence, CFU’s assumption remains just that.)

    Frank: Plausible peer-reviewed research (ie., Seager et al) says the SEUS drought can’t be attributed to AGW. More generally, you can’t attribute any single “weather” event to AGW.

    (My thought, FWIW: First point seems fair enough; I have some reservations about Seagar et al, as expressed above (with all due humility, I hope), but the bottom line does seem to be that there is no strong evidence to support a specific attribution. The second point seems to be a reach, however; for instance, the 2003 heat wave has, in some fashion at least, been partially attributed: http://www.nature.com/nature/journal/v432/n7017/full/nature03089.html.)

    CM: Frank’s point #1 above. More generally, over-attributing is scientifically unsupported and plays into several popular denialist memes–such as the “religious cult” meme, the “alarmist” meme, and the “AGW-causes-everything-mockery” meme. (My examples, not anything CM said.)

    (My thought FWIW: CM is probably right about this. CFU’s position is not really susceptible of refutation, but, like a hypothesis that’s unfalsifiable, it seems unlikely to advance the state of our knowledge: what are we supposed to do as a consequence of CFU’s points? (Though I did like the statistical point about the 400 events, etc.) As a practical advocate on news sites, I do frequently get accused of the various “alarmist” faults I mentioned, and others too, so CM’s concern seems well-founded to me. We shouldn’t attribute where there isn’t specific evidence to say so, and if we use events (eg., Katrina) as examples, we should be clear about what we’re doing.)

    Comment by Kevin McKinney — 26 May 2010 @ 8:25 AM

  500. Rod B.,
    It may be somewhat harsh of me to expect precision from a layman. However, I do think that your tendency toward vague expression contributes to you difficulty in understanding the theory. First, I think that you get wrapped around the axle when it comes to the specific mathematical expressions without quite understanding the physics. My recommendation is to start with the physics.

    Start by understanding WHY absorption does not saturate with concentration. Look at how the wings of the distribution broaden. At the same time, we know that absorption is not going to increase linearly–because the light in the middle of the band gets absorbed very quickly. Start with that and then ask yourself what sorts of mathematical functions reflect this behavior. You will find that the logarithmic dependence is the most reasonable fit. It also makes sense given the rough power law shape of the wings of the distribution.

    When in doubt, start with the physics.

    Comment by Ray Ladbury — 26 May 2010 @ 10:16 AM

  501. Septic Matthew, the theory is of Earth’s climate. Anthropogenic causation of warming is a prediction of that theory–a confirmed prediction. In order to make this prediction go away from the theory, you would have to come up with a theory that explains ALL OF EARTH’S CLIMATE as well as the current theory without a significant sensitivity to CO2. If you do that, I’ll start to have doubts about anthropogenic causation.

    Comment by Ray Ladbury — 26 May 2010 @ 10:19 AM

  502. Kevin: “CFU: …Specifically, every drought event must logically be worsened.”

    Where did I say that?

    I didn’t.

    Why are you attributing that to me and then argue against it being true?

    Specifically, every drought event *** absent any causation that undoes the warming and drying effect *** must logically be worsened.

    I’ve given examples of what you could do to show that in one event that AGW had an effect of easing the drought.

    Why then are people attributing an absolute to me I have given examples that refute its absolutism????

    Comment by Completely Fed Up — 26 May 2010 @ 10:36 AM

  503. re: #471
    It isn’t a question of “natural vs anthropogenic”, it’s a question of “how much” of each, i.e., it’s an attribution problem (and I see Gavin just started a new thread on that.) There is zero “excluded middle” issue.

    As for references, one of the later ones on (several) of Ruiddiman’s various hypotheses is:
    The early anthropogenic hypothesis: Challenges and responses, Reviews of Geophysics, October 2007.
    Section 10 is “Did pandemics contribute to drops in atmospheric CO2?”, but other sections a lot of relevant discussion on forestration issues vs acreage used.
    However, this is a little old, as much has happpened since.
    There have been a bunch of papers (in various combinations) by RJ Nevle, DK Bird, RA Dull and others, such as:
    Effects of syn-pandemic fire reduction and reforestation in the tropical Americas on atmospheric CO2 during European conquest, Palaeogeography, Palaeoclimatology, Palaeoecology
    Volume 264, Issues 1-2, 7 July 2008, Pages 25-38.

    I think I mentioned this one:
    Kauffman, J.B., Hughes, R.F. and Heider, C. 2009: Carbon pool and biomass dynamics associated with deforestation, land use, and agricultural abandonment in the neotropics. Ecological Applications 19, 1211-1222.

    Frank, D.C., Esper, J., Raible, C.C., Buntgen, U., Trouet, V., Stocker, B. and Joos, F. 2010: Ensemble reconstruction constraints on the global carbon cycle sensitivity to climate. Nature 463, 527-530. [that’;s for context, but the quote, p.529, is interesting:
    “Although occurring around the coldest period
    of the past millennium (Fig. 2a), the LIA CO2 decline is unique in the context of the past two millennia, both in magnitude and in its rate of change.”

    But in any case, keep an eye out for that forthcoming issue of The Holocene.

    The way I’d summarize all this is that archaeologists & geographers have been beavering away for years, and finding there were a lot more people in the pre-Columbian Americas than thought (several) decades ago, and that they farmed a lot more land than was thought. There is of course, a lot of anthropological literature on climate vs civilizations (of popular books, Brian Fagan’s come to mind).

    Ruddiman generated several hypotheses of possible anthropogenic influences on climate (early CO2, early CH4, inhibition of reglaciation, plague influence on CO2 via reforestration). Of the latter, one can identify 3 separate sets, i.e., post-Roman, 1400s, and ~1600, of which the ~1600 CO2 dip is particularly sharp.

    Although related, these are individual hypotheses and each needs quantification, bounding of uncertainty, attribution studies that compare versus alternate hypotheses, the usual back-and-forth arguments, etc. All that has been going on for at least 5 years, but the publications are spread out over a bunch of authors and journals, as is typical of seriously-interdisciplinary problems.

    Comment by John Mashey — 26 May 2010 @ 10:47 AM

  504. “It isn’t a question of “natural vs anthropogenic”, it’s a question of “how much” of each, i.e., it’s an attribution problem ”

    I wonder since attribution often gets used as an absolute (X is attributed to Y, therefore X was caused solely by Y), could we use “apportioned” instead?

    It’s pretty hard to turn that into an absolute.

    Comment by Completely Fed Up — 26 May 2010 @ 11:14 AM

  505. Kevin #499,

    Thanks for the summary. IIRC, the statements that “over-attributing” hurts credibility should be, uh, attributed to Frank, rather than to me. Not that I disagree. As for the partial of attribution single events,, that was a possibility I recalled a while back, and I referenced the Stott paper then.

    Comment by CM — 26 May 2010 @ 12:15 PM

  506. CFU:

    Kevin: “CFU: …Specifically, every drought event must logically be worsened.”

    Where did I say that?

    I didn’t.

    Why are you attributing that to me and then argue against it being true?

    I was summarizing in order to try to create some clarity in this discussion. I had the feeling that none of us were quite sure any more who said what–I guess, given your response & CM’s, that that was true for me, at least!

    So now both you & I know that I missed part of your point. I’ll have to go back and check your example(s), if I get a chance. (So hard to keep up, sometimes!)

    Comment by Kevin McKinney — 26 May 2010 @ 1:07 PM

  507. re 505, apart from the made up bit, you mean. If you summarise you’re not supposed to make stuff up.

    Comment by Completely Fed Up — 26 May 2010 @ 1:12 PM

  508. > archaeologists & geographers have been beavering away for years,
    > and finding there were a lot more people in the pre-Columbian Americas

    And similarly, the marine biologists have found that there were a whole lot more top predators in the oceans, because science didn’t get invented until well after the changes in populations started. The time span during which human effects first showed up needs more attention.

    Here’s one assessment of where primary productivity (photosynthesis) happens, and so where changes will show up in the atmosphere:
    http://www.globalchange.umich.edu/globalchange1/current/lectures/kling/energyflow/typeeco2.gif

    Compare that to this:
    http://scienceblogs.com/deepseanews/jackson%282008%29.jpg

    Comment by Hank Roberts — 26 May 2010 @ 1:25 PM

  509. Mr. Roberts, it gets even more interesting in the SW USA, where deforestation (what little was there) helped turn it into a place unsustainable for cities.

    CFU, open invitation for a beer if you get to Alabama. Oddly enough, we’ve spent a huge amount of time talking past each other.

    I had a conversation last week with a very liberal friend who was confused about climate change and was relieved when I pointed out that 1) yes, it’s a real problem that requires action, and that 2) climate is driven by nature, but that the change in that climate is largely being driven by us. It transcends political affiliation as a problem; the conflict arises in solutions.

    We’re the second job on the weekends in the budget. Did the extra cash pay for the cable bill this month, or was that covered by the main fulltime job? Hard to say as the money is all put together in one account and we had cable before (with tight and flush months as well), but one knows the cash available has increased spending ability. Turn it backwards and stop working on the weekends and it’ll have a negative effect.

    This assumes that one is a normal American and isn’t putting the extra cash in the bank and is spending it instead.

    :)

    Comment by Frank Giger — 26 May 2010 @ 2:44 PM

  510. CFU, I didn’t “make anything up”–and sorry if I got you wrong. But, as I said,the whole point was to provide info to you and to me about what I was “receiving,” compared to what you (thought you) were sending.

    Mission accomplished–I guess.

    Comment by Kevin McKinney — 26 May 2010 @ 2:44 PM

  511. 501, Ray Ladbury, I think that you are using the word theory in an idiosyncratically narrow fashion. However, I will try to write AGW in place of “the theory of AGW” or some such.

    When a “theory” becomes a “fact” is much disputed. We accept as fact the originally posed theory that molecules and atoms absorb light, and in particular that CO2 absorbs and emits IR.

    Articles of Belief:

    Whatever might have been caused by AGW was caused by AGW.

    What clearly was not caused by AGW is a red herring.

    Any testable hypothesis other than AGW is a lie.

    Any mechanism not now known does not exist.

    [Response: What nonsense. No scientist subscribes to any of those 'articles'. Do try to be a little serious and not resort to such blatant strawman tactics. - gavin]

    Comment by Septic Matthew — 26 May 2010 @ 3:52 PM

  512. Septic Matthew says: 26 May 2010 at 3:52 PM

    [list of lazy canards]

    And Darwin embarked on his course of research specifically intending to overturn orthodoxy regarding Creation, right? Subsequent inquiries into natural selection and evolution were guided and shaped by what would most piss off the pious, is that the idea?

    No. Darwin was following his curiosity. The subsequent controversy was (and tiresomely still is, 150 years later) a consequence of the discovery, which began with absolutely no relationship to theology. As a matter of happenstance the conclusions collided with what made people feel happy and comfortable.

    Come on, surely you can do better?

    As to your waffling about the transition between theory and fact, here’s what the National Academy of Sciences said about the matter of anthropogenic climate change, a few days ago.

    Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. Such conclusions and theories are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities.

    You know better? Don’t be ridiculous.

    Comment by Doug Bostrom — 26 May 2010 @ 4:12 PM

  513. SM, First, anthropogenic warming is an inevitable consequence of the current theory of climate. This climate has proven to have tremendous explanatory and predictive power–not just wrt Earth but even for other planets–e.g. Mars and Venus.

    Second, a 30 year warming trend has been observed with characteristics that are easily understood in terms of climate theory.

    Third, there is no credible alternative theory. At most there are a patchwork of suggestions that attempt to account for a tiny portion of the evidence (and mostly fail).

    You are either doing science or you’re pudknocking. If you aren’t trying to deal with all the evidence, you ain’t doing science.

    Comment by Ray Ladbury — 26 May 2010 @ 4:17 PM

  514. Septic Matthew: “Articles of Belief:” I have seen some unbelievably odd things written about science before but is too far. Please justify this incredible statement by examples where climate scientists (or any scientist) are shown to subscribe to this fantasy.

    Comment by Phil Scadden — 26 May 2010 @ 4:58 PM

  515. Bottom line:

    AGW is real and full of detriments.

    AGW is probably not good for many drought prone areas and

    certainly going to worsen some droughgts.

    AGW will lead to some crop destruction and lower crop quality.

    Localized weather patterns cannot in and of themselves individually be

    directly attributed to AGW, but some are very likely to be influenced and

    when the signal and noise are better separated it is clear that not only

    internal variability is responsible. The trends make it more clear that

    AGW is at work. The laws of physics and inputs from the environment make the

    analysis more robust and with a higher degree of certainty.

    Comment by Jacob Mack — 26 May 2010 @ 6:36 PM

  516. > Please justify this incredible statement
    You realize this is equivalent to “please, pull the other one”?

    Comment by Hank Roberts — 26 May 2010 @ 6:56 PM

  517. The philosophy of science is a great pursuit but it can easily go down a dark road where everyone except the scientists “seem” to know what science is.

    Comment by Jacob Mack — 26 May 2010 @ 10:05 PM

  518. Kevin: “CFU, I didn’t “make anything up”–and sorry if I got you wrong.”

    Uh, if you said something that I didn’t say and attribute it to me, that’s called making it up

    “But, as I said,the whole point was to provide info to you and to me about what I was “receiving,” compared to what you (thought you) were sending.”

    OK, but how did you miss the 18 other times when I told people I wasn’t saying that?

    THIS is why 8 pages have been spent on this: people aren’t reading.

    Do you get me now?

    (PS what mission accomplished? You certainly didn’t understand me)

    Comment by Completely Fed Up — 27 May 2010 @ 2:24 AM

  519. “certainly going to worsen some droughgts.”

    I would put it “almost all droughts” by reason that to undo that worsening you need a rather specific confluence of events, and that “almost” is only there because out of thousands of events, even really unlikely events are liable to turn up.

    The worsening may be unimportant, because a drought is already pretty rotten to experience, so it has to be quite a bit worse to be noticed as worse, but worse it still is.

    Heck, athletes don’t drink alcohol the day before a match because, though they won’t be affected MUCH by it after 24+ hours, the effect could lose them the match.

    Comment by Completely Fed Up — 27 May 2010 @ 2:28 AM

  520. Speaking of studying the last millennium (or more), Don Easterbrook should just stop. This is becoming really embarrassing, it’s quite awful to see somebody go down this path, whatever the reason may be.

    Easterbrook’s been casting aspersions but he’s developed a bad case of blowback:

    Cooling-gate: the 100 years of warming Easterbrook wants you to ignore

    Comment by Doug Bostrom — 27 May 2010 @ 2:45 AM

  521. Jacob Mack makes a valid point:

    The philosophy of science is a great pursuit but it can easily go down a dark road where everyone except the scientists “seem” to know what science is.

    But an even “darker road” is that where “the scientists claim to know all there is to know about what climate science really is”.

    The “unknown” in climate science today remains far greater than the “known”.

    For “scientists” to claim otherwise is both ignorant and arrogant, and we all know what Einstein had to say about the two.

    Max

    [Response: Strawman. -gavin]

    Comment by manacker — 27 May 2010 @ 5:44 AM

  522. John Mashey (#503),
    Thank you for the references.
    The “excluded middle” I referred to is the notion that carbon cycle sensitivity does not subsume all “natural” processes, especially when the temperature variations are more regional than global. I think that was an “exluded middle” in Bill Ruddiman’s short posts in this thread but I’m of course not assuming he was so cavalier in his publications. There can of course be no “excluded middle” between “natural” and “anthropogenic” as such because, strictly speaking, “anthropogenic” is a subset of “natural”.

    [Response: No it isn't. In this context natural is exactly equal to non-anthropogenic. No more semantics please. - gavin]

    Comment by Anonymous Coward — 27 May 2010 @ 6:38 AM

  523. Ray @ 513:

    Third, there is no credible alternative theory. At most there are a patchwork of suggestions that attempt to account for a tiny portion of the evidence (and mostly fail).

    Well … there =are= credible alternatives for enough of the variation that it seems to be making a mess of the upward trend since 1998, but the only credible alternatives should end in the next 15 to 30 years, after which we’re royally screwed.

    A more complete response might be “The only alternatives are related to cyclical phenomena that are currently operating towards a cooling bias. However, as can be seen from the data, even with a strong cooling bias caused by the current Grand Solar Minimum, the data show that at best the temperature is holding stable at close to record levels. The upward trend will resume when the Grand Solar Minimum ends, at which time it may be too late.”

    Lots of spotless days in May. Total irradiation here on the ground is 80% or so of what it should be. Not a mystery to those of us who watch the sun all the time …

    Comment by FurryCatHerder — 27 May 2010 @ 9:22 AM

  524. FCH, I think Ray’s point is that those alternatives are part of the Theory Of The Climate that has the inevitable consequence of AGW when A’s are burning hydrocarbons.

    The climate models are a memplex consisting of lots and lots of things.

    SOME of those things are those things you’re pointing out as “credible alternatives”, but they are not alternatives because

    a) they don’t explain the climate on their own
    b) they are part of the Climate theory

    The alternatives are “Urban Heat Island”, “The Sun Did It”, “GCRs From A Weaker Sun” et al. They are purporting to explain the climate changes in the past and the present.

    Comment by Completely Fed Up — 27 May 2010 @ 10:31 AM

  525. FCH (#543)–not exactly heartening, is it?

    Sometimes I can really appreciate the psychological attraction of denialism: it would be so much more fun to just relax and play music, drink a beer and go hang out with some friends.

    Unfortunately, false comfort tends to cost dearly in the long run. And I resent that I may have to pay for the false comfort certain others foolishly allow themselves to indulge in.

    Comment by Kevin McKinney — 27 May 2010 @ 10:38 AM

  526. @Doug Bostrom #520:
    DON Easterbrook, not Greg. Greg(g) can plead ignorance, not being a scientist himself. Don can only blame himself being a bad scientist.

    Comment by Marco — 27 May 2010 @ 11:40 AM

  527. Marco says: 27 May 2010 at 11:40 AM

    AAGGGH! Thank you! I plead the late hour of the post. Moderators, please, can you correct that? Pretty please?

    I should know better; I’ve personally faced Dr. Easterbrook’s grim countenance as he ordered me to bicycle through a blizzard to retrieve a forgotten paper “within this half hour.”

    Comment by Doug Bostrom — 27 May 2010 @ 12:16 PM

  528. CFU @ 524:

    Thanks for the response. You misrepresented what I wrote, as usual.

    Comment by FurryCatHerder — 27 May 2010 @ 1:38 PM

  529. Gavin,
    This is not semantics. Anthropogenic seems good enough as a category when it comes to emissions from the exploitation of fossil fuels because they were sequestered long ago, the amount burned recently is so huge, tracers such as isotopes have been studied extensively and so on.
    But, with your definition of natural, how would one go about determining the natural amount of carbon in the biosphere? Most of the biosphere interacts massively with human activity. Homo is ancient enough that we have no basline.
    The invasion of the Americas might have increased the amount of carbon in the biosphere through forest regrowth. You might call that change anthropogenic. But the carbon would presumably have stayed in the biosphere to begin with if the indigenous civilizations hadn’t cut down the forests, right? So which carbon flow is anthropogenic and which one is natural? How much of the carbon in the geologically recent sediments is anthropogenic? And so on… the concept does not strike me as being very useful when looking at early modern and pre-modern history, never mind prehistory. Thinking and communicating tends to be easier when one uses coherent concepts.

    Comment by Anonymous Coward — 27 May 2010 @ 1:42 PM

  530. Kevin @ 525:

    Yes, it’s completely depressing. The reasons for accepting “CO2 done it” are pretty well-founded in the Science. Likewise, if “Solar Minimum” is at all the cause (and I believe it is), pretty soon “Solar Minimum” ends, no? I =do= disagree with IPCC projections, but only because getting off of fossil fuels is the only way to survive economically.

    So, if we stick with fossil fuels, we’ll destroy both the environment =and= the economy. We also risk being unable to make the transition from fossil fuels to renewables because it becomes increasingly more expensive to make the switch with each passing day.

    Comment by FurryCatHerder — 27 May 2010 @ 1:45 PM

  531. All quotes directly from articles from Science Direct:

    The vulnerability of ecosystem services to land use change
    M.J. Metzgera, c, , , M.D.A. Rounsevellb, L. Acosta-Michlikb, R. Leemansc and D. Schröterd

    aDepartment of Plant Sciences, Plant Production Systems Group, Wageningen University, P.O. Box 430, 6700 AK Wageningen, The Netherlands

    bDepartment of Geography, Université Catholique de Louvain, Place Pasteur, 3, B-1348 Louvain-la-Neuve, Belgium

    cDepartment of Environmental Sciences, Environmental Systems Analysis Group, Wageningen University, P.O. Box 47, 6700 AA Wageningen, The Netherlands

    dScience, Environment and Development Group, Center for International Development, Kennedy School of Government, Harvard University, 79 J.F.K. Street, Cambridge, MA 02138, USA

    Available online 18 January 2006.

    Abstract
    Terrestrial ecosystems provide a number of vital services for people and society, such as biodiversity, food, fibre, water resources, carbon sequestration, and recreation. The future capability of ecosystems to provide these services is determined by changes in socio-economic characteristics, land use, biodiversity, atmospheric composition and climate. Most published impact assessments do not address the vulnerability of the human–environment system under such environmental change. They cannot answer important multidisciplinary policy relevant questions such as: which are the main regions or sectors that are vulnerable to global change? How do the vulnerabilities of two regions compare? Which scenario is the least, or most, harmful for a given region or sector?

    The ATEAM project (Advanced Terrestrial Ecosystem Analysis and Modelling) uses a new approach to ecosystem assessment by integrating the potential impacts in a vulnerability assessment, which can help answer multidisciplinary questions, such as those listed above. This paper presents the vulnerability assessment of the ATEAM land use scenarios. The 14 land use types, discussed in detail by Rounsevell et al. (this volume), can be related to a range of ecosystem services. For instance, forest area is associated with wood production and designated land with outdoor recreation. Directly applying the vulnerability methodology to the land use change scenarios helps in understanding land use change impacts across the European environment. Scatter plots summarising impacts per principal European Environmental Zone (EnZ) help in interpreting how the impacts of the scenarios differ between ecosystem services and the European environments.

    While there is considerable heterogeneity in both the potential impacts of global changes, and the adaptive capacity to cope with these impacts, this assessment shows that southern Europe in particular will be vulnerable to land use change. Projected economic growth increases adaptive capacity, but is also associated with the most negative potential impacts. The potential impacts of more environmentally oriented developments are smaller, indicating an important role for both policy and society in determining eventual residual impacts.

    1. Introduction
    Many aspects of our planet are changing rapidly due to human activities and these changes are expected to accelerate during the next decades (IPCC, 2001a, IPCC, 2001b and IPCC, 2001c). For example, forest area in the tropics is declining (Geist and Lambin, 2002), many species are threatened with extinction (Thomas et al., 2004), and rising atmospheric carbon dioxide results in global warming (IPCC, 2001a, IPCC, 2001b and IPCC, 2001c). Many of these changes will have an immediate and strong effect on agriculture, forestry, biodiversity, human health and well-being, and on amenities such as traditional landscapes (Watson et al., 2000 and UNEP, 2002). Furthermore, a growing global population, with increasing per capita consumption of food and energy, are expected to continue emitting pollutants to the atmosphere, resulting in continued nitrogen deposition and eutrophication of environments (Galloway, 2001 and Alcamo, 2002). In the face of these changes, it is important to integrate and extend current operational systems for monitoring and reporting on environmental and social conditions (cf. Kates et al., 2001). Over the last decades many people have become increasingly aware of these environmental changes, such that they are now commonly recognised as ‘global change’ (Steffen et al., 2001). Many research projects and several environmental assessments are currently addressing these concerns at all relevant scales, frequently in multidisciplinary collaborations. However, integrating this wealth of information across disciplines remains a considerable challenge (Millenium Ecosystem Assessment, 2003).

    This paper aims to quantify global-change concerns, focusing specifically on changes associated with scenarios of land use change, by defining and estimating vulnerabilities. Both the vulnerability concept (Metzger et al., 2004 and Metzger, 2005) and the land use change scenarios (Rounsevell et al., 2005, Ewert et al., 2005 and Kankaanpaa and Carter, 2004 S. Kankaanpaa and T.R. Carter, Construction of European Forest Land Use Scenarios for the 21st Century. The Finnish Environment 707, Finnish Environment Institute, Helsinki (2004).Kankaanpaa and Carter, 2004; Rounsevell et al., this volume) described in this paper were developed as part of the ATEAM project (Advanced Terrestrial Ecosystem Analysis and Modelling). Detailed information about the project can be found on its website (http://www.pik-potsdam.de/ateam).

    Assessment on vulnerability of sorghum to climate change in India
    Aditi Srivastavaa, S. Naresh Kumar, a, and P.K. Aggarwala

    a Division of Environmental Sciences, Indian Agricultural Research Institute, New Delhi 110012, India

    Received 4 December 2009; revised 17 April 2010; accepted 21 April 2010. Available online 15 May 2010.

    Abstract
    It is important to analyse the impacts of climate change on target production system. However, it is more important to deduce possible adaptation strategies so that the research and developmental policies can be guided to meet the challenges of climate change. Impacts of climate change on the sorghum production system in India are analysed using InfoCrop-SORGHUM simulation model. In general, impact of climate change is projected to be more on winter crop in central (CZ) and south-central zones (SCZ), while in south-west zone (SWZ) the impacts are likely to be higher on monsoon crop. Climate change is projected to reduce monsoon sorghum grain yield to the tune of 14% in CZ and SWZ and by 2% in SCZ by 2020. Yields are likely to be affected even more in 2050 and 2080 scenarios. Climate change impacts on winter crop are projected to reduce yields up to 7% by 2020, up to 11% by 2050 and up to 32% by 2080. Impacts are projected to be more in SWZ region than in SCZ and CZ. But, the yield loss due to rise in temperature is likely to be offset by projected increase in rainfall. However, complete amelioration of yield loss beyond 2 °C rise may not be attained even after doubling of rainfall in south-central zone (SCZ) and in central zone (CZ). Results indicate that adaptation strategies like changing variety and sowing date can reduce the vulnerability of monsoon sorghum to about 10%, 2% and 3% in CZ, SCZ and SWZ regions in 2020 scenario. Adaptation strategies reduced the climate change impacts and vulnerability of winter crop to 1–2% in 2020, 3–8% in 2050 and 4–9% in 2080. This indicates that more low-cost adaptation strategies should be explored to further reduce the net vulnerability of sorghum production system in India.

    Keywords: Sorghum; Climate change; Impacts; Adaptation; VulnerabilityClimate change, water availability and future cereal production in China
    Wei Xionga, b, , , Ian Holmanc, Erda Lina, b, Declan Conwayd, Jinhe Jiange, Yinlong Xua, b and Yan Lif

    aInstitute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, China

    bThe Key Laboratory for Agro-environment & Climate Change, Ministry of Agriculture, Beijing 100081, China

    cNatural Resources Department, Cranfield University, Bedfordshire MK43 0AL, United Kingdom

    dUniversity of East Anglia, Norwich NR4 7TJ, United Kingdom

    eInstitute of Quantitative and Technical Economics, Chinese Academy of Social Sciences, Beijing 100732, China

    fWater Resources Information Center, The Ministry of Water Resources of The People’s Republic of China, Beijing 100053, China

    Received 25 September 2008; revised 17 August 2009; accepted 21 August 2009. Available online 10 September 2009.

    Abstract
    Climate scenarios from a regional climate model are used to drive crop and water simulation models underpinned by the IPCC A2 and B2 socio-economic development pathways to explore water availability for agriculture in China in the 2020s and 2040s. Various measures of water availability are examined at river basin and provincial scale in relation to agricultural and non-agricultural water demand and current and planned expansions to the area under irrigation. The objectives are to understand the influences of different drivers on future water availability to support China’s food production. Hydrological simulations produce moderate to large increases in total water availability in response to increases in future precipitation. Total water demand increases nationally and in most basins, but with a decreasing share for agriculture due primarily to competition from industrial, domestic and municipal sectors. Crop simulations exhibit moderate to large increases in irrigation water demand which is found to be highly sensitive to the characteristics of daily precipitation in the climate scenarios. The impacts of climate change on water availability for agriculture are small compared to the role of socio-economic development.

    The study identifies significant spatial differences in impacts at the river basin and provincial level. In broad terms water availability for agriculture declines in southern China and remains stable in northern China. The combined impacts of climate change and socio-economic development produce decreases in future irrigation areas, especially the area of irrigated paddy rice. Overall, the results suggest that there will be insufficient water for agriculture in China in the coming decades, due primarily to increases in water demand for non-agricultural uses, which will have significant implications for adaptation strategies and policies for agricultural production and water management.

    1. Introduction
    Irrigated agriculture is the primary consumer of water and accounts for over 70% of total water use. More than 75% of China’s grain production is from irrigated land. Irrigation plays an important role in food security and poverty alleviation in China. Water stress is already affecting China’s grain production, particularly in the northern parts of the country (Li, 2006). Climate change, population growth, and economic development will affect the future availability of water resources for agriculture, with differing impacts in different regions. The demand for and supply of water for irrigation will not only be influenced by changing hydrological regimes (through changes in precipitation, potential and actual evaporation, and runoff at the watershed and river basin scales), but also by concomitant increases in future competition for water with non-agricultural users (Rosenzweig et al., 2004).

    There has been limited research on the coupled impacts of climate change and socio-economic development on agricultural production and water availability in China (Tao et al., 2003 F.L. Tao, M. Yokozawa, Y. Hayashi and E.D. Lin, Future climate change, the agricultural water cycle, and agricultural production in China, Agric. Ecosyst. Environ. 95 (2003), pp. 203–215. Abstract | Article | PDF (525 K) | View Record in Scopus | Cited By in Scopus (27)[Tao et al., 2003], [Rosenzweig et al., 2004], [Yuan et al., 2005] and [Xiong et al., 2009]). This paper aims to improve the understanding of how changes in crop water demand and water availability due to climate change will interact with other socio-economic pressures out to 2050. Results are presented for two periods, 2011–2030 (the 2020s) and 2031–2050 (the 2040s). We use the framework introduced in Xiong et al. (2009) which integrates several of the important challenges by linking socio-economic scenarios (SES), climate change scenarios, detailed simulation of impacts on cereal irrigation demand (for wheat, maize, and rice, China’s main staple cereals) and water availability. We explore in detail the spatial variation in water availability and demand by river basin and province. The objectives are to understand the influences of different drivers on future water availability to support China’s food production and to identify key vulnerabilities in the system and potential adaptation strategies

    Comment by Jacob Mack — 27 May 2010 @ 2:31 PM

  532. I want to add that no one should rely upon just one or two papers or just the IPCC report alone. When one has a general science and math background the IPCC report and many journals complement specialized field textbooks and manuals.

    Regional variation predictions based upon models and of course empirical data are different for each aforementioned demographics.

    AGW is past the point of being dismissed as a hypothesis or a theory in the lay person’s sense. AGW really is a fact like evolution is a fact.

    Water availability is a real issue as the planet approaches a population of 7 billion AND global climate change is further affected by green house gas emissions.

    Food productivity is a real issue too as crop yields are affected by under and over irrigation, floods, droughts AND these aspects are affected by anthropgenic means:humankinds actions.

    The birth of agriculture is a mixed blessing as it enabled more permanent settlements to be established, by living off the land and with the added nutritional value agriculture provided humans were able to produce more offspring. “To be fruiful and multiply,” was a very good idea thousands of years ago. Similarly the birth of corporations (not defending early Mercantilism or Imperialism under an oligarchy) and the subsequent development of mass production was also not an inherent “evil.” However, the globe, and more specifically, vulnerable regions faces issues of over population, rules of a wealthy few or outright dictatiors, and as in China an oppressive regime where the common workers do not have access to the goods and services they need. When one considers the older, but still relevant Hierarchy of Needs By Abraham Maslow along with more modern works, one can cleasrly see that AGW reduction/ minimizing policies need not victimize the indigent in the third world and in other developing countries. Rather, it is the worsening effects of AGW in combination with: population booms, air, water and terrestial pollution, and enhanced regional weather extremes that truly threatens them.

    No one who regularly posts here that I have seen nor any of the moderators is calling for an overnight stop to GHG emissions as that is impossible. No one is sugegsting to shut down such a percentage of GHG emitting technologies without some forms of replacement and supplementation.

    Some of us disagree on whether to use nuclear energy or not, or on how much and when GHG emissions should be lowered and how much conservation fits into the equation, but those of us who know the science behind AGW is sound are not making unreasonable requests.

    Some exnvironemtalists and conservationsists who are not scientifically literate make a bad name for the rest of us. Sometimes they do more harm than good; they may be well meaning, but they are the ones that think we should use wind power for the world alone, or they hug every tree hooked up to a chain, but do not really make an impact on the problem.

    Comment by Jacob Mack — 27 May 2010 @ 2:47 PM

  533. Finally I will end with this today, as this is not my blog:

    “Review
    Consequences of climate change for European agricultural productivity, land use and policy

    This article is not included in your organization’s subscription. However, you may be able to access this article under your organization’s agreement with Elsevier.

    Jørgen E. Olesen, , a and Marco Bindib

    a Department of Crop Physiology and Soil Science, Danish Institute of Agricultural Sciences, P.O. Box 50, DK-8830 Tjele, Denmark

    b Department of Agronomy and Land Management, University of Florence, P. le delle Cascine 18, 50144 Firenze, Italy

    Received 1 August 2001; revised 8 January 2002; accepted 20 January 2002. Available online 19 February 2002.

    Abstract
    This paper reviews the knowledge on effects of climate change on agricultural productivity in Europe and the consequences for policy and research. Warming is expected to lead to a northward expansion of suitable cropping areas and a reduction of the growing period of determinate crops (e.g. cereals), but an increase for indeterminate crops (e.g. root crops). Increasing atmospheric CO2 concentrations will directly enhance plant productivity and also increase resource use efficiencies.

    In northern areas climate change may produce positive effects on agriculture through introduction of new crop species and varieties, higher crop production and expansion of suitable areas for crop cultivation. Disadvantages may be an increase in the need for plant protection, the risk of nutrient leaching and the turnover of soil organic matter. In southern areas the disadvantages will predominate. The possible increase in water shortage and extreme weather events may cause lower harvestable yields, higher yield variability and a reduction in suitable areas for traditional crops. These effects may reinforce the current trends of intensification of agriculture in northern and western Europe and extensification in the Mediterranean and southeastern parts of Europe.

    Policy will have to support the adaptation of European agriculture to climate change by encouraging the flexibility of land use, crop production, farming systems etc. In doing so, it is necessary to consider the multifunctional role of agriculture, and to strike a variable balance between economic, environmental and social functions in different European regions. Policy will also need to be concerned with agricultural strategies to mitigate climate change through a reduction in emissions of methane and nitrous oxide, an increase in carbon sequestration in agricultural soils and the growing of energy crops to substitute fossil energy use. The policies to support adaptation and mitigation to climate change will need to be linked closely to the development of agri-environmental schemes in the European Union Common Agricultural Policy.

    Research will have further to deal with the effect on secondary factors of agricultural production, on the quality of crop and animal production, of changes in frequency of isolated and extreme weather events on agricultural production, and the interaction with the surrounding natural ecosystems. There is also a need to study combined effects of adaptation and mitigation strategies, and include assessments of the consequences on current efforts in agricultural policy to develop a sustainable agriculture that also preserves environmental and social values in the rural society.

    Author Keywords: Global warming; Climate change; Crops; Livestock; Policy; Impact assessment; Adaptation; Mitigation; European agriculture.”

    Look at the date; not very new, but similar to recent publications on this subject.

    Cover cropping affects soil N2O and CO2 emissions differently depending on type of irrigation
    Cynthia M. Kallenbach, a, , , Dennis E. Rolstona and William R. Horwath1, a,

    a Dept. of Land, Air, and Water Resources, University of California, Davis, CA 95616, United States

    Received 27 July 2009; revised 18 February 2010; accepted 23 February 2010. Available online 23 March 2010.

    Abstract
    Agricultural management practices such as subsurface drip irrigation (SDI) and winter legume cover cropping (WLCC) influence soil water dynamics as well as carbon and nitrogen cycling, potentially changing emission rates of soil CO2 and N2O, principal greenhouse gases. A split plot tomato field trial in California’s Central Valley was used to evaluate the use of SDI and WLCC on event-based CO2 and N2O emissions. SDI and WLCC were compared to the region’s more conventional practices: furrow irrigation (FI) and no cover crop (NCC). Our results indicate that SDI offers the potential to manage cover crops without the significant increases in greenhouse gas production during the growing season as seen under FI cover-cropped systems. The highest N2O emissions occurred during the beginning of the rainy season in November in the FI–WLCC treatment (5 mg m−2 h−1) and the lowest in August in the SDI–NCC treatments (4.87 μg m−2 h−1). CO2 emissions ranged from 200 mg m−2 h−1 during the rainy season (winter) and >500 m−2 h−1 during the growing season. Though no differences were detected in CO2 emissions between irrigation practices, mean CO2 emissions under WLCC were 40% and 15% greater compared to NCC under FI and SDI, respectively. The treatment with the greatest effect on CO2 and N2O emissions was WLCC, which increased average growing season N2O and CO2 emissions under FI by 60 μg N2O m−2 h−1 and 425 mg CO2 m−2 h−1 compared to NCC. In SDI there was no effect of a cover crop on growing season CO2 and N2O emissions. In the rainy season, however, SDI N2O and CO2 emissions were not different from FI. In the rainy season, the cover crop increased N2O emissions in SDI only and increased CO2 emissions only under FI. Subsurface drip shows promise in reducing overall N2O emissions in crop rotations with legume cover crops.

    Keywords: N2O; CO2; Greenhouse gas; Irrigation management; Cover crop; Tomato; Nitrogen fertilizer management

    1. Introduction
    Greenhouse gas (GHG) production in cultivated soils is highly dependent on the type of agricultural practice, such as fertilizer additions and irrigation and cover crop management (Mosier et al., 1998). In Mediterranean climates, such as in California, intensive irrigation and N fertilization can lead to conditions that promote elevated CO2 and N2O emissions (Linn and Doran, 1984). This is particularly true for flood irrigation practices such as furrow irrigation (FI) that inundate the soil profile during irrigation events. However, little information exists to contrast GHG emissions from furrow versus defined irrigation delivery systems such as subsurface drip irrigation (SDI). SDI could potentially mitigate GHG production from agricultural systems by delivering water directly to crop roots in small quantities but higher frequencies compared to the inundate/dry cycle of FI. The restricted soil-wetting pattern of SDI leaves much of the soil profile and soil surface dry in comparison to FI (Hanson et al., 2000), while keeping a water-filled pore space (WFPS) of around 20–30% in the area immediately surrounding the drip line (Hanson and May, 2007). Maintaining a lower WFPS in SDI compared to FI may limit denitrification which is tightly coupled with a WFPS > 60% (Ruser et al., 2006). Furthermore, though FI delivers water less frequently than SDI, the flooding characteristics of FI lead to severe wet–dry stresses in the soil. Wet–dry cycles in the soil profile have been shown to elevate the amplitude of CO2 pulses as well as increase nitrification and N2O losses ([Rudaz et al., 1991], [Appel, 1998] and [Fierer and Schimel, 2002]).

    The use of winter legume cover crops (WLCCs) can add a substantial amount of C to the soil, mitigating a portion of agricultural soil CO2 emissions (Jarecki and Lal, 2003). However, this benefit can be offset by subsequent increases in N2O production. Cover crops, particularly N-rich legumes, increase the amount of available C and N in the soil and thus, the microbial activity that drives CO2 and N2O emissions may no longer be substrate limited ([Varco et al., 1987], [Aulakh et al., 1991], [Watson et al., 2002] and [Sainju et al., 2007]). The use of hairy vetch as a winter cover, for example, can supply between 60 and 150 kg ha−1 of N (Christopher and Lal, 2007) and, if not synchronized well with the following crop’s needs, could lead to an abundance of available C and an excess in soil-N, potentially enhancing denitrifier activity or nitrate leaching (Follet, 2001). The push to include winter cover crops to address winter runoff, water quality and soil sustainability issues requires further information on the interaction of cover crops with different irrigation practices and subsequent influence on seasonal GHG emissions ([Rosecrance et al., 2000] and Poudel et al., 2001 D.D. Poudel, W.R. Horwath, J.P. Mitchell and S.R. Temple, Impacts of cropping systems on soil nitrogen storage and loss, Agric. Syst. 68 (2001), pp. 253–268. Abstract | View Record in Scopus | Cited By in Scopus (18)[Poudel et al., 2001).”

    We do have adpatation options which can actually lower some GHG emissions within the agricultural sciences. We can modify irrigation practices along with protection of soil nutrients. There are of course various trade offs, which we already knew:)

    Comment by Jacob Mack — 27 May 2010 @ 3:02 PM

  534. 511, Gavin: Do try to be a little serious and not resort to such blatant strawman tactics. – gavin]

    OK

    But that was “a little serious”, just not “very serious”.

    Comment by Septic Matthew — 27 May 2010 @ 3:21 PM

  535. re: #529
    This is the sort of semantic quibbling that just wastes time, because the *context* of the discussion was the specific drop in CO2 ~1600AD.

    It’s not a question of some “natural” level of CO2, assuming no one had ever cut down trees, or “natural” level of CH4, assuming no one ever did rice paddies or had cows. Those are *separate* questions, whose extent of anthropogenic influence are two of Ruddiman’s hypotheses, starting thousands of years earlier, and involving fairly long-term feedbacks.

    The plague hypotheses, especially the one involving the America’s die-off, are somewhat different, as they involve much shorter-term interactions and boundaries (like: die-offs in some places induce serious reforestration, and in others, they do not, like: the hectares/person varies by region adn over time). Sometimes, a short-term perturbation (like Pinataubo) offers good opportunities for analysis, because you at least you can ignore longer-term effects. As noted elsewhere, such effects don’t have to be unique to be useful.

    So, without getting tangled in semantic quibbling, I observe one fact, and a few interesting real questions:

    FACT: the CO2 drop ~1600 was unusual, even allowing for the usual error bars in measurements and timing.

    The questions have been mentioned earlier, but in this case they come down to:

    A: (natural drop): some combination of solar irradiance changes, volcanoes + usual CO2 feedbacks and maybe oceanic jiggles accounts for the entire drop. All that is a delta off the ongoing temperature/CO2 state (which Bill would argue was already different from equivalent timing in past interglacials, but that doesn’t matter to this argument). it is slightly awkward for the soalr part that the Maunder Minimum timing follows teh CO2 drop, but maybe timing is off.

    OR
    B: The (anthropogenic) i.e.die-off and reforestration contributed some noticeable part of the CO2 drop, which fed into the (natural) processes in A.

    People are crunching away trying to bound the various uncertainties. I still harbor some hope that if it runs out that B is plausible, there will be more work on regional fingerprint differences, and just possibly, that will shed light on differences among reconstructions. (Rutherford, et al certainly does some of that, but to end as usual “more research is required.”)

    Comment by John Mashey — 27 May 2010 @ 3:35 PM

  536. Kevin, when you attribute something to someone else that wasn’t theirs, “this is making it up”.

    In what way is this misrepresenting YOU?

    You misrepresented what I said, but when I point it out, *you’re* the one being maligned????

    Comment by Completely Fed Up — 27 May 2010 @ 4:45 PM

  537. Costello: … Because. Why? I don’t know! He’s on third and I don’t give a darn!

    Abbott: What?

    Costello: I said I don’t give a darn!

    Abbott: Oh, that’s our shortstop.

    Comment by Hank Roberts — 27 May 2010 @ 6:22 PM

  538. You deniars do see al the independent references we are putting up yes? Septic, FCH et al.

    I have plenty more independent lines of epxeriments, observations, proxy data, GCM results, sattelite data, crop yield analysis references available.

    Forget Google scholar and Google books, there is Science Direct and Springer Link:)

    There is lots of data on both atribution and prediction too. Granted prediction can be more difficult to resolve, but no one in the fields analyzing this stuff denies that AGW is real and poses real detriments.

    Comment by Jacob Mack — 27 May 2010 @ 10:34 PM

  539. There is an attempt here http://davidhortonsblog.com/2010/05/28/swings-and-arrows/ at talking about the implication of climate change in the past for climate change in the future. Aimed at the general public. Might be useful for others to do something similar?

    Comment by David Horton — 28 May 2010 @ 3:27 AM

  540. Jacob Mack

    Let me comment on your very thoughtful 532/533 posts.

    Leaving the validity of the IPCC reports aside, I believe it is valid to say that the rise of agriculture has changed our planet, as the many links you cite confirm.

    It is also beyond doubt that AGW per se is “more than a hypothesis or a theory”, and should be considered a “fact” (just like “evolution”).

    But I believe that the argument is one of degree.

    Here are the “facts”: CO2 is a greenhouse gas. GHGs absorb and re-radiate LW energy emitted from our planet’s surface, thereby contributing to warming. Without this effect our planet would probably be 33C colder than it is today, and CO2 alone is probably responsible for 5 to 8C of this natural GH effect. Atmospheric CO2 has increased since measurements at Mauna Loa started in 1958, and probably before this time, as estimated by ice core data. Humans (especially those in the industrially developed societies) emit CO2 from fossil fuel combustion. This has probably been the primary cause for the 0.4% compounded annual growth rate in atmospheric CO2 for the past 5 (or 50) years.

    Now we come to “theories and hypotheses”: a doubling of CO2 would theoretically cause GH warming of around 1C according to GH theory. Yet, if one assumes strongly net positive feedbacks with warming, primarily from water (as vapor, liquid droplets in low clouds or ice crystals in high clouds) as estimated by model simulations, one can arrive at a theoretical 2xCO2 climate sensitivity of 2.0 to 4.5C.

    So we have both “facts” and “hypotheses” at work here.

    But back to agriculture. It certainly did change our planet. It may have been a “mixed blessing” for all of the prior flora and fauna on our planet (many of which subsequently became extinct), but for mankind it was 100% positive, in that it was the key to the start of human civilization, as we know it.

    It also opened the door (much later) to increased human literacy, the Renaissance, the Age of Reason, the many discoveries of science, the Industrial Revolution, discoveries in medicine and hygiene, the age of computers, rapid communication and “instant information”, etc., all of which we take for granted today.

    You mentioned “water availability” as a limiting item for a “world population exceeding 7 billion”, which may be exacerbated by AGW. This may be so.

    You also mention food productivity as “a real issue too as crop yields are affected by under and over irrigation, floods, droughts AND these aspects are affected by anthropogenic means”. This is undoubtedly true. Will slightly warmer global temperatures and higher CO2 levels increase global crop yields, as some studies show or will the net result be negative?

    You also mention China and its oppressive regime. Having lived in China I can tell you that, despite the great amount of poverty that still exists, most Chinese are better off today than they were before the current economic upswing. This includes the young female garment workers from impoverished provinces in the north who work 40+ hour weeks in the Pearl River delta to send money back home, producing garments that are then sold in North America and Europe. The Chinese population is unlikely to “explode” under the new “one-child” rule (even if this rule is “oppressive”); it may even eventually stagnate and decline as the shortage of female children and the average age increase.

    India, which has a less oppressive regime (and no enforced “one-child” policy), may soon overtake China as the most populous nation. Is the average Indian better or worse off today than 10 years ago?

    You wrote:

    By Abraham Maslow along with more modern works, one can clearly see that AGW reduction/ minimizing policies need not victimize the indigent in the third world and in other developing countries. Rather, it is the worsening effects of AGW in combination with: population booms, air, water and terrestrial pollution, and enhanced regional weather extremes that truly threatens them.

    Opinions vary on this, Jacob. Two of the most urgent needs of the poorest individuals of this world as recognized by WHO and others, are a clean water supply and a reliable and cost-effective energy infrastructure, the lack of which together cause some 4 million deaths annually. Many of these nations have local fossil fuel deposits, which could act as the basis for building up a viable energy infrastructure. If we restrict the poorest nations to higher-cost “green” energy solutions, they will, by definition, be denied these most urgent needs for a longer period of time (and the 4 million per year will die a few years longer).

    I would agree wholeheartedly with your point that it is unreasonable to call “for an overnight stop to GHG emissions as that is impossible”, nor that one should suggest shutting down “GHG emitting technologies without some forms of replacement and supplementation”.

    You added:

    Some of us disagree on whether to use nuclear energy or not, or on how much and when GHG emissions should be lowered and how much conservation fits into the equation, but those of us who know the science behind AGW is sound are not making unreasonable requests.

    Unfortunately, nuclear energy has (rightly or wrongly) developed “political baggage” of its own (at least in the “industrialized Western nations”), which may be hard to overcome even with new thorium-based fast breeder technology or even with future nuclear fusion reactors.

    I agree fully with your point:

    Some environmentalists and conservationists who are not scientifically literate make a bad name for the rest of us. Sometimes they do more harm than good; they may be well meaning, but they are the ones that think we should use wind power for the world alone, or they hug every tree hooked up to a chain, but do not really make an impact on the problem.

    These may, in fact, have been some of those who promulgated the general fear of nuclear power, which now presents us with the political dilemma mentioned above.

    As to the studies you cited which call for policies to “support the adaptation of European agriculture to climate change”, these may well make sense, if we really know how climate is going to change. As the report states, I would see these mostly as “adaptation” measures, whereby we adapt to what is actually happening, rather than try to anticipate what might (or might not) really happen.

    I still am convinced that the weak link here is our knowledge of what the future will actually bring. If we “plan” for a future that is 3C warmer than today on average and it then turns out to be 1 or 2C cooler than today, we have “shot ourselves in the foot”.

    The most recent record has shown us that AGW has slowed down (or actually stopped) for a few years. Is this the start of a new “trend”? No one knows for sure, although the GH premise tells us that this is unlikely unless natural variability plays a greater role in our planet’s climate than we have previously assumed.

    Thanks for a very thought-provoking summary. I will check your cited references out more closely.

    Max

    Comment by manacker — 28 May 2010 @ 7:07 AM

  541. CFU, I was feeding back to you what I was getting from what you were saying.

    Last word. Deal with it or don’t.

    Comment by Kevin McKinney — 28 May 2010 @ 8:29 AM

  542. manaker @ 540:

    The most recent record has shown us that AGW has slowed down (or actually stopped) for a few years. Is this the start of a new “trend”? No one knows for sure, although the GH premise tells us that this is unlikely unless natural variability plays a greater role in our planet’s climate than we have previously assumed.

    No, the recent record has shown us no such thing. Nor is “GH” a “premise”.

    There are natural cycles, many of which have had a downward bias according to the folks who think they actually control climate. They are cyclical, they will return to a neutral or warming bias sooner or later. When that happens, the warming trend caused by growing CO2 concentrations will be there, except the warming that will result will be greater.

    Keep this in mind — the last time the sun was as quiet as it has been, the planet cooled. That we’re holding steady — more or less — at record high temperatures should completely disabuse any legitimate skeptics.

    Comment by FurryCatHerder — 28 May 2010 @ 8:34 AM

  543. #540, manacker–

    Note that the Charney sensitivity is more than merely “hypothetical,” as you describe it. Paleo data do help constrain the possible values to the range you mention, so this is not merely “assumed” (as you also describe it.)

    Comment by Kevin McKinney — 28 May 2010 @ 8:34 AM

  544. “Yet, if one assumes strongly net positive feedbacks with warming … one can arrive at a theoretical 2xCO2 climate sensitivity of 2.0 to 4.5C.”

    Nope, not just theory.

    Actual measurement shows this to be the case.

    “So we have both “facts” and “hypotheses” at work here.”

    Not yet, unless you count the errant hypothesis that your summation is true.

    Comment by Completely Fed Up — 28 May 2010 @ 8:42 AM

  545. Wow, Max@540, what happened? That was almost reasonable. However, I think you miss on a few points. First, the detailed interplay of feedbacks is not the only hold we have on CO2 sensitivity. We have a dozen or so independent lines of evidence telling us that CO2 sensitivity is around 3 degrees per doubling, that it is almost certainly not less than 2 or more than 4.5 degrees per doubling. The level of agreement is truly remarkable. It is a mistake to ignore that evidence.

    Second, I know of no studies that predict a significant overall increase in calories or grams of protein as a result of climate change. Most show a negative impact on most critical food crops.

    Third, your contention about warming having slowed is not borne out by this year’s data. The past 12 months have been the warmest on record, and 2010 is a good candidate to break the previous record.

    I would also contend that we are screwed and tatooed if we plan for 1 degree of warming and we get 3 degrees or 4.5 if we plan on 3 degrees. Can you think of a better guide than the best science available? The consensus of experts?

    On a personal note: when were you in China? I haven’t been there since 1985, so I’m sure it is unrecognizable. It’s also been 14 years since my last trip to India–although I did make it to the subcontinent last year.

    I would say that the question of welfare depends critically on who you ask in both India and in China. There are certainly winners and losers in their development.

    Comment by Ray Ladbury — 28 May 2010 @ 9:03 AM

  546. Let me reconsider my “last word” to CFU, for something hopefully more informative.

    CFU, when somebody tells you, “Here is what I understand you to be saying,” a helpful response is “No, what I am trying to say is—.”

    “You made that up” is a good deal less so.

    Hope that helps.

    Comment by Kevin McKinney — 28 May 2010 @ 9:11 AM

  547. “CFU, when somebody tells you, “Here is what I understand you to be saying,””

    Except you didn’t.

    You said:

    “CFU: every weather event must logically be affected by AGW. Specifically, every drought event must logically be worsened

    (My thought, FWIW: This can’t be refuted as possibly true, …”

    Nothing about “Here is what I understood”.

    As to No, what I am trying to say, please check posts

    #131 #147 #148 #157 #160 #173 #175
    #176 #223 #224 #237 #238
    #239 (a poll that you haven’t answered, and CM answered a different one…)
    #240 #241
    #246 (which includes a “how this could be shown false”
    #247 #255 #262
    #263 (note, he couldn’t manage that)
    #266 #278 #300 #301 #306 #318 #328
    #336 #337 #338 #383 #385 #414 #416
    #417 #419 #427 #428 #437 #440 #449
    #450 #466 #467 #497 #498 #502

    How many times do I have to explain?

    Comment by Completely Fed Up — 28 May 2010 @ 9:50 AM

  548. #131 #147 #148 #157 #160 #173 #175
    #176 #223 #224 #237 #238
    #239 (a poll that you haven’t answered, and CM answered a different one…)
    #240 #241
    #246 (which includes a “how this could be shown false”
    #247 #255 #262
    #263 (note, he couldn’t manage that)
    #266 #278 #300 #301 #306 #318 #328
    #336 #337 #338 #383 #385 #414 #416
    #417 #419 #427 #428 #437 #440 #449
    #450 #466 #467 #497 #498 #502

    That’s 47 attempts to explain what I mean.

    And you’re still making things up, Kev. cf “when someone tries to say…” when you didn’t.

    Comment by Completely Fed Up — 28 May 2010 @ 9:51 AM

  549. Ray Ladbury

    I am sure that you will agree that the empirical evidence for a GH effect and for CO2 being a GH gas is much stronger than that for the specific premise that the 2xCO2 climate sensitivity is between 2.0 and 4.5C, due to positive feedbacks.

    The actually observed warming since 1850 does not correlate that well with the actually observed increase in atmospheric CO2 and a CS of 2.0 to 4.5C. Paleo-climate evidence is much less robust that recent physical observations, due to the many uncertainties involved.

    I was last in China in late 2003, but spent quite a bit of time there between 2000 and then.

    Max

    Comment by manacker — 28 May 2010 @ 9:52 AM

  550. #547, #548–

    Whatever, dude.

    Comment by Kevin McKinney — 28 May 2010 @ 10:16 AM

  551. Yes, whatever I say you refuse to read and then complain I’m not saying what I think.

    Then, when I point you to where I’ve said it, go “Whatever, dude”. I suppose that’s easier than reading what you’ve asked me to write and means you can continue to believe yourself in the right.

    Comment by Completely Fed Up — 28 May 2010 @ 11:06 AM

  552. “Paleo-climate evidence is much less robust that recent physical observations, due to the many uncertainties involved.”

    It’s a lot less certain that the sensitivity is less than 1 than it is that it’s greater than 2.

    Yet somehow you’re concentrating on the 2.

    I don’t think you’re as worried about the certainties as you’re making out.

    Bah, what am I saying? You’re Max.

    Comment by Completely Fed Up — 28 May 2010 @ 11:09 AM

  553. Max,
    The greenhouse nature of CO2 is a fact–as certain as any scientific fact we have. However, if you look at the various distributions of probability of sensitivity for different lines of evidence, you find that those we understand best provide very little support for a sensitivity below 2–and if they are wrong, we get much more of our distribution going to high sensitivity than to low.

    Now this is a BIG problem, as the consequences of climate change scale roughly exponentially with the temperature change–to the point where for a sensitivity of 5 degrees per doubling risk is effectively unbounded.

    However, I think that the remarkable agreement is actually pretty significant. A quick Bayesian analysis places the probability of getting such agreement around 3 at less than 6.5% if the real sensitivity were below 2–and that’s a conservative estimate. So, in effect, you are betting the future of humanity on at least a 15:1 longshot. Since the alternatives are to go with the best science or to go diametrically against it, I have a hard time seeing how one would justify inaction.

    China is an amazing place. My brief time there left me amazed at how delicately balanced it was–and that was 25 years ago. India is certainly more chaotic, but it also seems more robust

    Comment by Ray Ladbury — 28 May 2010 @ 11:57 AM

  554. Manacker: the weight of the analysis of data indicates a clustering of 3 degrees increase in global mean temperature with a doubling of C02. It may be higher, but it is very unlikely to be lower and will not only be 1 degree and it is very probable to be above 2 degrees. It may be possible to be just under 3 degrees, but virtually impossible to be 2 degrees and it is impossible to be only 1 – 1.5 degrees.

    Now in reagards to crops Ray made a slight error in his response regarding no increased calories or crop yields. Some regions will have enhanced regional crop yields and regional crop qualities. As we all know once upon a time the poles were once warm with crops. There will most likely be new species of crops as well, some pests some viable for food, some neither.

    I think what Ray meant to say is that overall globally there will most likely be less crop yields / quality overall, which is fair assertion based upon current data. Between worsening droughts, floods, wind pattern shifts etc… many crops will potentially lower in yield and quality while others die.

    The answers to much of these concerns are: changing soil treatment techniques, fertilization techniques, irrigation methods, Biotechnology/ agricultural engineering, desalinization of oceans for potable water supply, and of course reducing overal GHG emissions.

    Comment by Jacob Mack — 28 May 2010 @ 12:46 PM

  555. Now on another point: yes the understanding of AGW is based upon physics, but keep in mind guys that paleo climate data is also very important too. Being that Gavin and others study paleo climate extensively and create reconstructions of past climate, there must be good reasons for it.

    Comment by Jacob Mack — 28 May 2010 @ 12:47 PM

  556. # 545 Ray, I want to make a little correction to my response to your post on “moat crops.” Somehow I missed that on the first read. I do agree there, but certainly some crops will flourish; not a gamble I want to make, however, under these circumstances.

    Comment by Jacob Mack — 28 May 2010 @ 12:50 PM

  557. Max is good at restarting long discursive arguments by rebunking claims and then arguing with people about them.

    If you want to convince the audience, point to actual references, don’t argue with Max. He likes when you argue — he gets to repeat himself.

    Debunk the claims. Point to good sources people can check for themselves.
    http://www.woodfortrees.org/notes.php#trends

    (Note: “This graph will stay up to date with the latest year’s values, so feel free to copy the image link to your own site, but please link back to these notes so people can understand it and play with it themselves.”)

    Comment by Hank Roberts — 28 May 2010 @ 1:21 PM

  558. Jacob,
    Point well taken. I think people do not realize how dependent we are on a very few crops in terms of producing calories and grams of protein. Nor, when they equate warmer with more productive, do they realize that fetid is not the same as fertile.

    I’ve lived in the tropics in agricultural areas and seen what farmers face. It ain’t pretty.

    I do think that we might be able to mitigate some of the threats–but ironically, the best tools for doing that–the models–are the ones our denialist friends distrust the most.

    Comment by Ray Ladbury — 28 May 2010 @ 1:29 PM

  559. #552 missed out &lt’s.

    Should say

    “more likely it;s

    “you’re concentrating on the less than 1 and not on the greater than 2″

    Comment by Completely Fed Up — 28 May 2010 @ 1:40 PM

  560. 513, Ray Ladbury: Third, there is no credible alternative theory. At most there are a patchwork of suggestions that attempt to account for a tiny portion of the evidence (and mostly fail).

    On that I agree with you. There are others who find the solar influence theory to be credible (though incomplete.)

    Comment by Septic Matthew — 28 May 2010 @ 2:40 PM

  561. Ray, # 558, completely agreed. When I was a child I lived on a farm with my grandmother, for a number of years in Massachusetts, and later on my family had a several acre garden we tended to as well. Now I live in the agriculture rich town of Hollister CA.

    People seem to forget that hundreds of thousands to millions of years ago we (and many current species of life) were not here on this planet, and so even with different climate conditions in the past survived and even thrived on by various species of animals and plants does not necessarily apply to us humans and our current collective ecosystems.

    I do think that we can do far more to reduce GHG emissions and mitigate future consequences through the methods I already aforementioned. The literature is pretty thick on such matters. I also know that good farmers can do a lot to protect their crops based upon what I have seen, albeit less time than yourself and others here.

    I do not think humanity will do all that it can to actually directly lower GHG emissions, to be perfectly honest, as there is far too many politicans and economic oligarchists too. I know there is a place for politics and economics and they can help provide answers to reducing the net positive impacts of AGW, but right now the state of the system continues to move awat from rational science based and feasible courses of action.

    Now according to the EPA and other sources, over the last several decades we have reduced air pollution by a large percentage and of course we all know that there is not as much acid rain even from when I was in elementary school. However, there are far many other issues and with the population of the globe approaching 7 billion, the probability of reducing GHG emissions anywhere near enough looks ever more bleak.

    This is why mitigation/adaptation is so important to me, atleast. We cannout power the world on wind and solar alone in the current economic climate as well as, regional weather aspects which makes either of these energy sources not viable. Look at Germany with its economic issues as they attempt to build still more solar panels while they continue to take in immigrants without skills or education as highlighted in recent issues of the Economist. The Greece recession and the general European financial crisis also makes it more difficult to fund such applications.

    It is amazing what Biotechnology can now accomplish as well as new agricultural growing techniques. More indoor farming techniques are also not out of the question.

    If I recall corrrectly, Ray, from a post a year or two ago here at RC you are ekptical as I am of over reliance upon nuclear energy. Does memory serve me correct?

    Comment by Jacob Mack — 28 May 2010 @ 2:47 PM

  562. Max Anacker — Actually the correlation over the last 13 decades with the instrumental record is quite good. As notice the steady upward march of temperatures for the past few decades; no slowdown at all. Finally, also note I make a prediction for the average temperature of the 2010s:
    http://www.realclimate.org/index.php/archives/2010/03/unforced-variations-3/comment-page-12/#comment-168530
    where the first formula ought to read
    AE(d) = k(lnCO2(d-1) – lnCO2(1870s)) – GTA(1880s)
    and the results are in good agreement with estimates of Charney climate sensitivity. If you want more along these lines read Tol, R.S.J. and A.F. de Vos (1998), ‘A Bayesian Statistical Analysis of the Enhanced Greenhouse Effect’, Climatic Change, 38, 87-112.

    Comment by David B. Benson — 28 May 2010 @ 2:58 PM

  563. #551 (against my better judgement)–”. . . and means you can continue to believe yourself in the right.”

    It’s not about being wrong or right. It’s about ceasing to waste my time (and everyone else’s on the blog.)

    Comment by Kevin McKinney — 28 May 2010 @ 3:23 PM

  564. Jacob Mack wrote: “We cannot power the world on wind and solar alone …”

    Yes, we can. We can harvest vastly more energy from wind and solar than the entire world currently uses, with today’s mature technologies that are already being commercially deployed, rapidly and at large scale — not to mention the far more powerful and far less expensive technologies that are already under development.

    Jacob Mack wrote: “It is amazing what Biotechnology can now accomplish …”

    The only significant thing that biotechnology has “accomplished” is to proliferate proprietary strains of crops that have been genetically engineered to resist a particular proprietary toxic herbicide, with the purpose and effect of increasing the use of that toxic herbicide, to the great profit of the corporation that produces it (and also produces the genetically engineered resistant crops).

    It’s interesting that you greatly underestimate the benefits of wind and solar technology, while simultaneously greatly overestimating the benefits of biotechnology. You might wish to consider where you are getting your information about both.

    Comment by SecularAnimist — 28 May 2010 @ 4:01 PM

  565. Secular Animist, Jacob Mack, before y’all launch yet another “it’s all this or nothing” conversation, would you please consider agreeing on a budget of replies in advance?

    Please give the idea some due consideration, then ignore it if you must.

    Comment by Doug Bostrom — 28 May 2010 @ 5:06 PM

  566. 564 Just the usual sources: peer reviewed journals‚ textbooks‚ peers in related disciplines, professors‚ engineers, and agricultural engineers. Now crops are being engineered to resist higher and lower temps‚ pests‚ herbicides, drier conditions, and less nutrient rich soil. High voltage lines can make wind mill generation of electricity more efficient and farther reaching but not global, and it is not being applied on a grand scale yet. Agricultural sciences as II already referenced has made both preliminary discoveries and advances in crop preservation. Now where are your references? I have many more on the way. Solar is a good way to get off the grid and wind a great supplement ‚ but not the full energy supply solution.

    Comment by Jacob Mack — 28 May 2010 @ 5:26 PM

  567. Doug sure. I will keep it short on my end.

    Comment by Jacob Mack — 28 May 2010 @ 5:36 PM

  568. max 540: The most recent record has shown us that AGW has slowed down (or actually stopped) for a few years. Is this the start of a new “trend”?

    BPL: How many times have we told you you need 30 years to establish a climate trend?

    Comment by Barton Paul Levenson — 28 May 2010 @ 7:24 PM

  569. Jacob (#561),
    What has immigration or the economic climate to do with emissions reduction? This is hand-wringing. Don’t listen to the politicians’ excuses. The issue is that there is no political will. If there was, emissions could be reduced quickly by picking the low-hanging fruits. On-demand electricity is way too cheap in Germany considering the amount of nuclear and its planned phase-out. So people keep wasting electricity and coal keeps getting burned in massive quantities.
    By the way: recessions actually make it easier, not harder for the governements of fully independent states to fund renewables and such. Europe as a whole qualifies though individual countries don’t. I won’t explain why as it’s way off topic but I’m sure you have heard that it’s generally recommended for governments to spend during recessions (recall the green jobs hype). There’s a reason for that. Blame your politicians if they deem military spending or roads to be priorities, not the economic climate.
    Demand emission cuts now, not vague promises or excuses.

    Comment by Anonymous Coward — 28 May 2010 @ 9:11 PM

  570. Anomymous Coward, # 569 you are partially correct. I wish it were that simple to demand change in energy use now, but the economic climate affects what policies get passed and when. I will get into more detail on these points in your post as they are definitely worth disucssing, but for now I need to cook dinner for my wife and relax my brain for the night:)

    Comment by Jacob Mack — 28 May 2010 @ 11:06 PM

  571. “BPL: How many times have we told you you need 30 years to establish a climate trend?”

    Every day for 30 years, I reckon…

    Comment by Completely Fed Up — 29 May 2010 @ 4:22 AM

  572. Septic Matthew@560,
    Those who champion a solar mechanism are a wonderful example of what I decry–looking only at tiny pieces of the evidence. There is simply no way a solar mechanism can explain simultaneous tropospheric warming and stratospheric cooling. Period. A solar mechanism would require an inordinately high climate sensitivity to explain the temperature record. Same with GCR.

    The fact of the matter is that a well mixed, long-lived greenhouse gas is absolutely essential if we are to understand Earth’s climate. It is essential to explain many of the characteristics we see occurring now. It is only by ignoring this evidence and by special pleading that the denialists can even come close to explaining what is after all only a tiny aspect of the evidence. They simply are not doing science.

    If they want to convince me and other sciences, they have only to come up with an alternative theory that explains the evidence–all of it–equally well or better with equal economy. Until then, they have nothing to offer and are firmly in the anti-science camp.

    Comment by Ray Ladbury — 29 May 2010 @ 7:20 AM

  573. Furry Cat Herder (542)

    The surface (Hadley) as well as satellite (UAH / RSS) temperature records show a slight linear cooling trend of “globally and annually averaged land and sea surface and tropospheric temperature” starting 2001. GISS shows an almost flat warming trend (+0.01C per decade). The average trend of the 4 records is –0.062C per decade or slight cooling.

    The upper ocean temperature as measured by the more reliable Argo system since 2003 also shows a slight cooling since then.

    These have occurred despite record increase in atmospheric CO2 as measured at Mauna Loa.

    This is obviously not a “long term trend”, nor is it a significant cooling trend, but it is what it is: some (such as Josh Willis) have called it a “speed bump” in global warming, others have used other expressions.

    Max

    Comment by manacker — 29 May 2010 @ 7:33 AM

  574. BPL

    How many times have we told you you need 30 years to establish a climate trend?

    Can’t tell you “how many times” (but this is immaterial, anyway).

    Actually, 30 years is a “blip”.

    160 years (1850-2009) is probably long enough to represent a “climate trend”.

    9 years is (admittedly) also a “blip” (maybe you would prefer to call it a “mini-blip”).

    Max

    Comment by manacker — 29 May 2010 @ 7:39 AM

  575. Jacob,
    OK, per Doug’s admonition, this will be my only statement on nukes, etc.

    There are 4 problems I see with nuclear energy:
    1)nuclear waste–we have no good, long-term solution to this problem. I do think we can greatly ameliorate this problem by recycling waste, while at the same time increasing the lifetime of nuclear fuel–albeit at the expense of increasing proliferation concerns.

    2)Proliferation is, of course, the second problem. It can be ameliorated by selection of the fuel cycle, but it will remain a concern.

    3)Human stupidity–Every major nuclear accident has been precipitated by some ingenious fool who figured a way to cut corners around safeguards. Human stupidity is boundless.

    4)It is a temporary solution at best and a distraction from finding a sustainable solution at worst. We’ve seen how entrenched interests have sabotaged efforts to resolve the current crisis. It is not an experience humanity wants to repeat.

    Having said this, nuclear power may provide some of the energy needed in the interim. It is certainly preferable to burning coal. This point was driven home last year on a trip to Sri Lanka. The island has always met its meager energy needs mainly with hydroelectric power. Now, with the ind of the civil war, it’s economy is again growing rapidly and it needs energy. Ironically, although it has lots of uranium and thorium, it is building a big coal-fired powerplant, which, I think, is a mistake.

    My preferred solutions are, in order:
    1)Conservation
    2)renewables
    3)nukes
    4)natural gas

    Leave the coal in the ground–and while we’re at it bury the CEOs of Massey, Exxon and BP with it.

    Comment by Ray Ladbury — 29 May 2010 @ 7:41 AM

  576. Furry Cat Herder

    Whether you download the temperature data from the 4 records and plot it in Excel (as I did) or let “Wood For Trees” do it for you, you get the same result for the first 9 full years of the 21st century (as I indicated earlier).

    BPL tells me this is too short to be a climate trend, which I have agreed all along.

    I think this requires at least a century to be meaningful (while BPL thinks 30 years is long enough), and the entire 160-year Hadley record is probably even a better example of a “climate trend”.

    But opinions vary on that.

    Max

    Comment by manacker — 29 May 2010 @ 8:02 AM

  577. #568 BPL

    How many times? I think the answer is infinite. After all, it seemed to take an infinity of times telling Max that climate models do not assume constant relative humidity before he eventually conceded the point. Or did he? I’m sure if we prod him enough he would come out and say it again.

    Anyway, we all know that Max is not here in good faith, he is simply here to accumulate bruises that he can show to his fellow deniers. So let’s not disappoint him, eh?

    So, Max, why is Arctic ice melting at an unprecedented rate this year, eh? Is it because we are in the middle of a cooling trend?

    Comment by CTG — 29 May 2010 @ 8:07 AM

  578. DB Benson

    Thanks for link to your decadal temp vs CO2 analysis plus forecast for 2010s.

    Will go through it and give you any comments I may have.

    Max

    Comment by manacker — 29 May 2010 @ 8:09 AM

  579. Max, 30 years is not an arbitrary standard. Rather, you can show that you need at least 22-25 years to even determine the sign of the trend, and the additional 8 years to get a good estimate of its magnitude. Tamino has looked at this.

    Comment by Ray Ladbury — 29 May 2010 @ 10:37 AM

  580. CTG (576) wrote:

    So, Max, why is Arctic ice melting at an unprecedented rate this year, eh? Is it because we are in the middle of a cooling trend?

    Probably the same reason that Antarctic sea ice is growing (changes in ocean currents, wind patterns, etc.?).

    Max

    Comment by manacker — 29 May 2010 @ 10:39 AM

  581. CTG

    You asked me (576) “why is Arctic ice melting at an unprecedented rate this year, eh?”.

    Suggest you check the record:
    ftp://sidads.colorado.edu/DATASETS/NOAA/G02135

    The last month, for which data are published, is April. The NSIDC record shows (extent in msk):
    15.00 (1979-2000 average = baseline)
    14.58 2009
    14.69 2010

    April 2010 is 2% below the baseline average (1979-2000).
    April 2010 is 1% higher than April 2009.

    I do not see “an unprecedented rate” here, CTG Do you?

    By contrast, the extent in April 2007 was at a low point of 13.88 msk, so the sea ice has recovered by about 6% since then.

    Max

    BTW

    Comment by manacker — 29 May 2010 @ 10:57 AM

  582. > Manacker
    Find a more reliable source, don’t just assert belief; help the reader.
    http://moregrumbinescience.blogspot.com/2009/01/results-on-deciding-trends.html

    Comment by Hank Roberts — 29 May 2010 @ 11:00 AM

  583. Manaker @ 573 and 575:

    Well … yeah, and that’s a collection of points I’ve been making for a while. If you click on my name you’ll get a thing I posted on Facebook a bit more than 2 years ago because I felt that I needed to be able to say “See, I told you so!” to the folks who insist that the Sun plays no role in climate.

    But as I point out in that post, this “respite” or “speed bump” is a temporary thing and we need to exploit the hell out of it and shift to renewables, and away from carbon-based fuels, as fast as we possibly can.

    If we assume that SC24 is going to be a 14 or 15 year cycle, that’s what we’ve got to act — about another 10 to 12 years. We can’t rely on SC25 being another fizzle — we have to assume that SC25 is closer to average and if we’ve not gotten a handle on CO2 emissions that the 20′s and 30′s are going to be HOT.

    As for Ray and the other “The sun didn’t do it!” crowd, “Solar cycles play a role” does explain the current sideways trend, as well as the temperatures during the Dalton and Maunder minima. Deal with it.

    – Julie.

    Comment by FurryCatHerder — 29 May 2010 @ 11:35 AM

  584. Max #573, there is no cooling trend in the Hadley or GISS dataset since 2001.

    Comment by Completely Fed Up — 29 May 2010 @ 12:45 PM

  585. “I wish it were that simple to demand change in energy use now,”

    It’s easy: demand energy change now.

    Use less.

    Use the clothesline to dry your clothes.

    Go shopping three times a week and walk it.

    Waste less.

    There’s no time lag on that.

    Comment by Completely Fed Up — 29 May 2010 @ 12:47 PM

  586. 584 CFU all good points. As a matter of choice we gave up the car 2 years ago, I walk everywhere in town, including all grocery shopping, we do not use a washer and dryer at home, we use heat only for one when needed, we recycle, and use only energy efficient appliances. My former post to AC referred to my desire to see more green tech implemented here.

    Comment by Jacob Mack — 29 May 2010 @ 2:03 PM

  587. Ray 574 fair enough. I agree on all points except I Iike natural gas better than nuclear due to the disposal issues you mentioned.

    Comment by Jacob Mack — 29 May 2010 @ 2:08 PM

  588. #580 Max the eternal optimist…

    Of course, it is now nearly the end of May, so in a couple of days time you will be able to post the May figures. You might want to reconsider your words then, as the 2010 is now not only well below the 2SD range, but is tracking well below the 2007 line.

    As with most of the things you say, you are out of date, Max.

    Comment by CTG — 29 May 2010 @ 2:28 PM

  589. Note how Max is careful to choose his timframes: “the first 9 full years of the 21st century” is referring to this, which does indeed show three trends going down, and one going up.

    But why leave out the first fourth months of this year, Max? Oh that’s why. UAH is now heading up. How inconvenient of it.

    And if the trends are sensitive to the end date, are they also sensitive to the start date? Oops, looks like they are.

    But maybe that’s unfair, as that’s a longer timeframe than Max’s 2001-2009, so let’s restrict it to 2000-2008. Oh dear.

    You see, Max, when trends like these are so sensitive to start and end dates, it should be telling you something – specifically, it should tell you that you are using too short a window. None of the trends I have plotted so far – up or down – are particularly relevant to deciding whether it is warming or not, as they are not long enough to remove the internal variability.

    As has been pointed out to you on many, many occasions, you need 30 years to determine trends.

    Is there the remotest possibility that you are going to listen this time, Max, or are you going to be back in a couple of weeks spouting the same old nonsense?

    Comment by CTG — 29 May 2010 @ 3:05 PM

  590. Hank Roberts

    You advise me to “find a more reliable source” for 21st century temperature data.

    I went to the source of the data (Hadley, GISS, UAH and RSS published records), which I then plotted in Excerl. Then I checked the “Wood for Trees” rehash (which agrees with my Excel curve).

    I recking the root source of the data is a more reliable source that your cited “rehash” article. Don’t you?

    Max

    Comment by manacker — 29 May 2010 @ 3:08 PM

  591. People need to find a more reliable source than Max. He’s an expert at keeping any digression going so long as comments feature his name. Eschew.

    Want facts about science? I recommend Robert Grumbine.

    Comment by Hank Roberts — 29 May 2010 @ 3:15 PM

  592. CFU

    You wrote (584):

    Max #573, there is no cooling trend in the Hadley or GISS dataset since 2001.

    The annual records for 2001 through 2009 show:

    You are correct for GISS, which shows a warming trend of +0.01C per decade.

    You are wrong for Hadley, which shows a cooling trend of -0.06C per decade.

    Both satellite records (UAH and RSS) also show cooling trends.

    Check the records out for yourself.

    Max

    Comment by manacker — 29 May 2010 @ 3:18 PM

  593. Ray Ladbury (579)
    CTG (589)

    Regardless of what you have both posted, 30 years is an arbitrary period for determining climate change (probably too short).

    The IPCC “poster period” (AR4 WG1) is from 1976 to 2005, a period in which CO2 emissions were growing at 0.4% compounded annual growth rate (and there is a good CO2 / temperature correlation).

    The statistically indistinguishable period 1910-1944 occurred before there was as much increase in CO2.

    Another similar period occurred in the late 19th century, when there was almost no CO2 increase.

    In between there were slight cooling periods (also of about 30 years length).

    If one believes that a 30-year cycle can be used for determining “climate change”, then one should look at all these 30-year oscillations and their causes, and find an explanation for the fact that some of these observed cycles show no statistical correlation with observed changes in atmospheric CO2

    If one prefers the longer-term look, one should look at the entire 160-year period of warming. That would be my advice.

    Max

    Comment by manacker — 29 May 2010 @ 3:35 PM

  594. CTG

    You may not be aware of this (many people are not), but the 21st century started New Year’s Eve 2000/2001 (and 2001 is the first year in the 21st century).

    So I have shown the records for the first 9 full years of the 21st century.

    This will not change much by “splicing on” the first four months of 2010.

    One can also “cherry-pick” the starting date as 1998, which shows a different trend, but still confirms that the past few years have been flat to slightly cooling.

    Arbitrarily “cherry picking” the last year of the 20th century and adding it on (as you have done) is simply an exercise in “sticking one’s head in the sand” to deny the fact that it has been cooling slightly since the 21st century started.

    I am not claiming that this is a “trend”. Kevin Trenberth called it a “travesty”, but I would simply call it a “blip”.

    [Response: That's not what Trenberth was referring to, and you are ignoring the steady increase in upper ocean heat content--jim]

    Can you understand this?

    Max

    Comment by manacker — 29 May 2010 @ 3:48 PM

  595. Max 573: The surface (Hadley) as well as satellite (UAH / RSS) temperature records show a slight linear cooling trend of “globally and annually averaged land and sea surface and tropospheric temperature” starting 2001.

    BPL: No, they do not. And you still don’t appear to understand what a “trend” means. It’s not “a direction in the curve of arbitrary length.” A “trend” has to be statistically significant.

    Comment by Barton Paul Levenson — 29 May 2010 @ 3:51 PM

  596. max 574: 160 years (1850-2009) is probably long enough to represent a “climate trend”.

    Super. Hadley CRU mean global annual dT regressed on year gives

    dT = -8.625 + 0.004382 Year + ε

    with t statistics of -16.43 and 16.11 on the intercept and Year term coefficient, respectively–a positive trend significant at p < 4.38 x 10-35. 62% of variance is accounted for. N = 159.

    Comment by Barton Paul Levenson — 29 May 2010 @ 3:57 PM

  597. max 576: I think this requires at least a century to be meaningful (while BPL thinks 30 years is long enough), and the entire 160-year Hadley record is probably even a better example of a “climate trend”.
    But opinions vary on that.

    BPL: No. “Opinions” are irrelevant. Statistical significance is something that can be measured.

    You need to take an introductory statistics course before you try to debate this issue. You just don’t know the basics.

    Comment by Barton Paul Levenson — 29 May 2010 @ 3:59 PM

  598. Julie 583,

    TSI or Sunspot number accounts for no more than 2.5% of the variance of dT 1880-2008. Deal with it.

    Comment by Barton Paul Levenson — 29 May 2010 @ 4:02 PM

  599. FurryCatHerder

    I personally agree that you are spot on with the impact of SC24. Whether SC25 will be another fizzle is anyone’s guess, and I know there are opinions out there that this will be the case (which I am sure you have seen).

    The “respite” (or “speed bump”) may be a temporary thing, or it may be the start of a 30-year cycle of slight cooling before a warming cycle again takes over (as has happened in the past).

    I also agree that trying to myopically tie everything to human CO2 while ignoring natural forcing, such as occurred during the Dalton and Maunder minima, for example, is simply a form of denial.

    My point in all this is simply that there is still a whole lot that we do not fully understand about what makes our climate do what it does and (as a result) what the quantitative impact of increased CO2 concentrations will really be.

    You may be right that once fizzling solar cycles stop we may be in for a significant warming oscillation, putting us back on the long-term underlying warming trend of 0.04 to 0.05C per decade. Or the long-term trend line may shift upward to something like 0.1C or even 0.2C per decade. But, despite all the model simulations, etc., it’s still anyone’s guess what will happen.

    Max

    Comment by manacker — 29 May 2010 @ 4:11 PM

  600. Jacob Mack
    Ray Ladbury

    Natural gas is a good clean source of energy and can easily be used for motor vehicles. Recent estimates tell us that there are enormous sources in shale, assuring a supply for well over 100 years, even at accelerated consumption rates.

    Nuclear fission has the disposal problem, which Ray mentioned, but new thorium-based fat breeder technology may go a long way to solve this problem. There is no real long-term shortage of fuel for nuclear fission.

    The other problem is that spent fuel can be converted to military use, so it would not make sense for every politically unstable nation to have nuclear power.

    Nuclear fusion is also a future possibility. My personal prediction is that it will become a reality before cost-competitive wind or solar power does (except for isolated small uses), due to the inherent unreliability (or limited on-line factor) of both wind and sun.

    I also believe that “Ol’ King Coal” will be around for a long time to come, as these lower CO2 alternates become reality.

    Max

    Comment by manacker — 29 May 2010 @ 4:30 PM

  601. 572, Ray Ladbury: If they want to convince me and other sciences, they have only to come up with an alternative theory that explains the evidence–all of it–equally well or better with equal economy. Until then, they have nothing to offer and are firmly in the anti-science camp.

    I agree with sentence 1 but not sentence 2. I used to think that the solar theorists were mostly cranks, but now I think that their evidence is non-ignorable. As far as I can tell, all of the scientists discredit some of the evidence for reasons that I find insufficient. Say there’s no large body of evidence substantiating a hypothetical causal mechanism underlying the correlation between solar activity and earth temperature swings. Here, the old saying applies: Absence of evidence is not evidence of absence, and there are bits and pieces of evidence. Hence, to me the lack of a complete mechanism is not sufficient to discredit. Some stuff causes cancer without the mechanism being known. Some people seem not to get AIDS from HIV, and no one knows how.

    For warming or cooling or random variation humans require more energy and are running out of oil. The development of new energy supplies is something that about 75% of people agree on, with the biggest disagreement being about federal funding of nuclear power. India, China, and Russia have no worry about federal funding, only we Americans have a worry. I, C and R will show (I bet) the feasibility of using what is now called “nuclear waste” as fuel, so the US won’t lag much, if at all.

    Comment by Septic Matthew — 29 May 2010 @ 4:47 PM

  602. Max Anacker — Looking forward to yuor comments on “Global warming, decade by decade”. My goal is something sufficiently simple that most can follow without overly simplifying, just keeping it simple.

    Comment by David B. Benson — 29 May 2010 @ 5:34 PM

  603. FCH@583,
    Oh, come on. Who do you know wh says the sun plays no role. You’re sequestering a lot of carbon in all that straw! The last solar cycle was long–the second longest in about 150 years. However, it is nothing like the levels of a Dalton or Maunder minimum.

    I would appreciate it if you would take sufficient time to represent my views as they are rather than distorting them so even I don’t recognize them. For the record: Yes, Mr. Sun does play a role. However, even if we were to get a Grand Minimum, it would buy us at most a few decades. The effects of CO2 persist for centuries. I have never contended otherwise and I do not appreciate your distortion of my views.

    Comment by Ray Ladbury — 29 May 2010 @ 5:41 PM

  604. Interesting here in California the recent rainfall and cooler temperatures were such that only a handful of times in the last 150 years for this time of year matched these conditions. Of course there would be some who might try to jump on that fact and make a false claim that warming is done basd upon an ephemeral regional, but relatively drastic weather change. The climate is certainly changing overall and this example of precipitation changes and cooler temperatures in terms of regional weather is a good example of such predictions made by GCM’s the IPCC report and the literature we have been citing here.

    It is easy to confirm what I am saying: wacthed it on the weather channel, and four major network news programs with their various meteorologists.

    Comment by Jacob Mack — 29 May 2010 @ 9:00 PM

  605. Ray – 575 – I fear that your point 3 about nuclear power and human stupidity is even worse than you make it out.

    That’s because it’s more human cupidity than stupidity. Take something that’s undetectable to normal human senses, but really dangerous, such as radiation. There is a permanent financial incentive to treat it and dispose of it carelessly. It saves money, and the consequences are invisible – for a while.

    Eventually, regulation gets lax, more safety measures are ignored or disposed of, and a disaster results. (Rather like oil extraction and coal mining, to name a couple of more visible but ignorable dangers.)

    In that sense, it clearly resembles the buildup of CO2 itself, and will (partially) substitute a different problem of the same general type.

    Comment by John Pollack — 29 May 2010 @ 9:51 PM

  606. Jacob – 598 I believe that the GCM’s are doing a fairly good job with the big picture, but I am unimpressed with attempts to derive regional trends in my part of the world (western U.S. Corn Belt).

    For quite a while, many of the GCMs have been suggesting we get a hotter and drier growing season. However, what I saw in 31 years as an NWS forecaster was wetter with little temperature trend.

    A lot of the wet comes from moisture recycled through evapotranspiration and convection, and much of the rest from moisture transport from the Gulf of Mexico.
    In either case, I don’t trust the GCM’s to get it right when the higher resolution daily forecast models can’t do it reliably! They tend to break down when it comes to evaluating vertical stability, and require human interpretation to produce reasonable results.

    That said, I’m not drawing firm conclusions. It is clear from the last millennium that we are subject to multi-decadal droughts and wet periods. Perhaps we are enjoying one of the latter. Perhaps there is enough positive feedback between moisture and vegetation, heightened by AGW, that the next drought will by a biggie, and dwarf our current wet tendency.

    Comment by John Pollack — 29 May 2010 @ 10:08 PM

  607. BPL @ 595:

    What’s the trend for sin(x) for x = 0 to 2 pi radians?

    Oh, right — 0!

    [Response: Just for kicks, fit a linear model to that at say steps of pi/6 and see what slope you get.--Jim]

    Comment by FurryCatHerder — 29 May 2010 @ 11:37 PM

  608. 606 thanks for your response. I will be looking more into GCM predictions and regional variations later next week.

    Comment by Jacob Mack — 30 May 2010 @ 12:54 AM

  609. “What’s the trend for sin(x) for x = 0 to 2 pi radians?”

    Which has relation to this discussion HOW?

    Or are you saying that temperature is a sinusoid? If so, how is this *correlation* *caused*?

    Comment by Completely Fed Up — 30 May 2010 @ 5:40 AM

  610. “I am not claiming that this is a “trend”.”

    cf earlier statements:

    “temperature records show a slight linear cooling trend”

    Max, there is no cooling trend in the records since 2001.

    Comment by Completely Fed Up — 30 May 2010 @ 5:42 AM

  611. #
    “592
    manacker says:
    29 May 2010 at 3:18 PM

    CFU

    You wrote (584):

    Max #573, there is no cooling trend in the Hadley or GISS dataset since 2001.

    The annual records for 2001 through 2009 show:”

    They show no cooling trend.

    Tell me, Max, you’ve done the maths here.

    Is there any statistically significant cooling trend in the data?

    Comment by Completely Fed Up — 30 May 2010 @ 5:45 AM

  612. SM 601: Some people seem not to get AIDS from HIV, and no one knows how.

    BPL: HIV-immune people have a defective gene that normally makes cell walls permeable, but in them (recessive trait requiring two parents with the defective gene), the cell wall blocks HIV entrance. I think this news is a few years old now.

    Comment by Barton Paul Levenson — 30 May 2010 @ 5:48 AM

  613. “My former post to AC referred to my desire to see more green tech implemented here.”

    Jacob, not wasting resources is THE GREENEST tech possible.

    cf Micawber:

    “Annual income twenty pounds, annual expenditure nineteen pounds nineteen and six, result happiness. Annual income twenty pounds, annual expenditure twenty pounds ought and six, result misery.”

    Comment by Completely Fed Up — 30 May 2010 @ 5:48 AM

  614. Septic Matthew,
    The problem with the solar models is that they could at most explain a tiny fraction of the evidence–for instance, they couldn’t explain the stratospheric cooling in conjunction with tropospheric warming. Also, to get such correlation, the solar scientists have to introduce artitrary parameters–e.g. lags–and you know how risky this is with a purely statistical model. Without a mechanism, I just can’t take these guys seriously. It is not sufficient to merely show a correlation between solar cycle and temperature. Lots of things change with solar cycle.

    Finally, none of the work the solar guys have done changes the fact that we have very strong evidence that CO2 sensitivity is around 3 degrees per doubling. The evidence there is overwhelming. Ironically, if the solar guys are right, it might wind up implying a higher CO2 sensitivity rather than a lower one.

    That is my problem with all these guys trying to “disprove” global warming. They are looking only at the temperature record–nothing else. That’s not science. What they need to be doing is trying to understand the climate rather than focusing only on late 20th century warming. Show me the model.

    Comment by Ray Ladbury — 30 May 2010 @ 7:28 AM

  615. John Pollack,
    Very true. We need to always remember the way the Mongol hordes breached the Great Wall–by bribing (and eventually killing as unreliable) a guard.

    My comment was more directed at plant safety. The idjits at Chernobyl had to bypass–I think it was–8 failsafes to bring about their own little version of hell on Earth. Every significant nuclear accident has involved astounding stupidity.

    Perhaps what both cupidity and stupidity have in common is the fact that humans suck at gauging risk. That is why there’s a whole science of doing so–if we’d just frigging use it.

    Comment by Ray Ladbury — 30 May 2010 @ 7:58 AM

  616. It always amuses me when people get pedantic about when the 21st century started. Generally, the people getting all warmed up about the subject don’t understand why the date is when it is, don’t understand why the “right” choice is the wrong choice for most situations, and don’t understand why it couldn’t matter less in nearly all contexts.

    In short, exactly the same deficiency exhibited by climate deniers. Understand the whole problem, don’t just be contrary for the sake of being contrary.

    Comment by Didactylos — 30 May 2010 @ 9:24 AM

  617. CFU writes:
    > Tell me, M ….

    Oh, he loves seeing his name and claims repeated, and having people ask him to go on saying his stuff. You’re hooked, sir. Spit out the hook.

    Comment by Hank Roberts — 30 May 2010 @ 9:38 AM

  618. BPL # 612: Right the chemokine CCR5 deletion along with other receptor changes (a co-receptor).

    CFU: again agreed, and we produce as little waste as possible.

    Comment by Jacob Mack — 30 May 2010 @ 11:59 AM

  619. Ray – 615, I didn’t know that about the Mongols. Good illustration!

    I agree totally that humans suck at gauging risk (especially long-term).
    Risks with invisible causes (radiation, climate change)are worse, if possible.

    Science certainly helps a lot, but there are a disturbing number of “black
    swan” unanticipated risks that even get by the science.

    In the case of climate change, while the deniers like to yammer about the economic risk that we take expensive conservation measures for no “good” reason, I’m a lot more concerned about very rapid change.

    For example, there is a reasonable tendency for climate scientists to interpret paleo data conservatively, and not call for an extreme change unless absolutely forced to by the data. There are disturbing hints that the climate system is vulnerable to very rapid change.

    For example, the melting of the Greenland Ice Sheet in the last interglacial. From the concluding paragraph of “High rates of sea-level rise during the last interglacial” Rowling et. al. Nature Geoscience 1, 38-42 : “A 1.6 m global sea-level rise per century would correspond to the disappearance of an ice sheet the size of Greenland in four centuries
    (modeling suggests 1000 years or more.)”

    What if a mere 300 ppm CO2, with somewhat different orbital parameters, really is enough to melt the GIS in 400 years? We’re in a heap of trouble!

    Comment by John Pollack — 30 May 2010 @ 12:02 PM

  620. Ray @ 603:

    Have you ever read my post on Live Journal? What you wrote is exactly how I explain it. However, my overall point is that by reacting to various and sundry arguments — arguments that are often true on a shorter time scale, such as the length of a solar cycle or two — the way they are reacted to, all you do is feed the denialist engine.

    If you read this post on Skeptical Science — http://www.skepticalscience.com/solar-cycle-length.htm — it states that until 1975, there was a strong relationship between solar cycle length and global temperature. But SC23 wasn’t as weak a cycle as SC24 is shaping up to be, which indicates to me that there is a stronger cooling bias during SC24 than during SC23. That we’ve gone 12 years without a new record high for HadCRUT would seem to confirm this.

    To me, that’s the better message — acknowledging that there has been an influence, but that whatever the influence it is either being swamped, or will end with SC24 in another decade.

    Comment by FurryCatHerder — 30 May 2010 @ 12:59 PM

  621. CFU @ 609:

    What’s the graph of y = mx + b + a * sin(cx)?

    Pick various values of m, x, b, a and c. Let a * sin(cx) be the change in temperature associated with solar activity. Let mx be the CO2 related rise in global temperature. Let b be the baseline temperature. Let a be the change in temperature attributable to the length of a solar cycle. Let c be a scale factor for Grand Minima and Maxima.

    Do there exist values such that the temperature rises on multi-decadal scales while still going sideways, or even downward, during deep solar minima? See the Skeptical Science post I referenced earlier for an answer to that.

    Now, if that’s true — that past relationships between solar cycle length and global temperature have existed — wouldn’t it be =better= to acknowledge that, as well as the implications of that, than to make snarky responses?

    Comment by FurryCatHerder — 30 May 2010 @ 1:08 PM

  622. John Pollack @ 619:

    Worse scenario — what if 300ppm is enough to cause another global Ice Age in 500 years and the only solution is burning everything made of carbon we can get our hands on?

    One reason to sequester carbon in places where we can get to it is that some day we may =need= to have 450ppm CO2. Sure, let’s get back to 280 or so. But let’s not shoot ourselves in our collective feet the next time Mr. Ice Man cometh.

    Comment by FurryCatHerder — 30 May 2010 @ 1:11 PM

  623. FurryCatHerder (620) — Look at the past 13 decades this way:
    http://www.realclimate.org/index.php/archives/2010/03/unforced-variations-3/comment-page-12/#comment-168530

    Comment by David B. Benson — 30 May 2010 @ 2:05 PM

  624. FCH @ 622: Considering that 300ppm is at the high end of what we’ve been seeing during interglacials in the past 800k years or so, I’m not concerned about inviting another glacier in 500 years if we were somehow able to return to that value (which is not by any currently reasonable technology). 250 ppm and you’d have a point, but we can’t get it that low. 450 ppm looks immensely more likely before we get a handle on emissions, if then.

    450 ppm puts us back in the Middle Miocene, when temps were 3-6C higher than present, and sea level 25-40m higher. I refer to Tripati et. al. in Science 326, 1394-7. The full article is still paywalled, but the abstract isn’t:

    Coupling of CO2 and Ice Sheet Stability Over Major Climate Transitions of the Last 20 Million Years
    Aradhna K. Tripati,1,2,* Christopher D. Roberts,2 Robert A. Eagle3

    The carbon dioxide (CO2) content of the atmosphere has varied cyclically between ~180 and ~280 parts per million by volume over the past 800,000 years, closely coupled with temperature and sea level. For earlier periods in Earth’s history, the partial pressure of CO2 (pCO2) is much less certain, and the relation between pCO2 and climate remains poorly constrained. We use boron/calcium ratios in foraminifera to estimate pCO2 during major climate transitions of the past 20 million years. During the Middle Miocene, when temperatures were ~3° to 6°C warmer and sea level was 25 to 40 meters higher than at present, pCO2 appears to have been similar to modern levels. Decreases in pCO2 were apparently synchronous with major episodes of glacial expansion during the Middle Miocene (~14 to 10 million years ago) and Late Pliocene (~3.3 to 2.4 million years ago).

    1 Departments of Earth and Space Sciences and Atmospheric and Oceanic Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA.
    2 Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, UK.
    3 Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA.

    Comment by John Pollack — 30 May 2010 @ 2:55 PM

  625. FCH (#622),
    As has been pointed out several times already, there are better GHG gases which could be synthesized for the purpose of avoiding a glaciation such as HFCs.

    Still no explanation from Jacob for the link he asserted between immigration and the lack of investments in renewables and/or emission cuts by the way…

    Comment by Anonymous Coward — 30 May 2010 @ 3:04 PM

  626. # 625: go to the Economist.com. Due to the high influx of unskilled immigrants and a weakening economy coupled with the high costs of solar panels, there is a deficit growing in Germany. There are also less people percentage wise who are skilled to design, build and maintain alternative energy applications.

    From that site you can do your own reading,as I promised to be brief on this topic so we can continue to have fruitful discussion,so any future responses from you will simply be ignored.

    Comment by Jacob Mack — 30 May 2010 @ 3:55 PM

  627. AC this will get you started:

    http://www.economist.com/countries/Germany/

    If you do not have a subscription you can get a 14 day free trial to see the full content. Little hints: solar panels are still very expensive to install and take awhile of use to pay for themselves. Standard power uses are still cheaper and allowing so many unskilled immigrants has reduced the productivity of technological development and application.

    FIN

    Comment by Jacob Mack — 30 May 2010 @ 4:05 PM

  628. Just when I thought I

    Comment by Jacob Mack — 30 May 2010 @ 4:08 PM

  629. Just when I thought I was done here:

    http://www.economist.com/specialreports/displaystory.cfm?story_id=15641057

    Comment by Jacob Mack — 30 May 2010 @ 4:11 PM

  630. David Benson @ 623:

    I have looked at a wide variety of data. That the article I referenced admits that pre-1975 there was a connection between solar cycle length and global temperature tells me that the link is still there, it’s simply been swamped by CO2. And that means that it becomes increasingly difficult for any other cause — besides CO2 — to change global temperatures. So, what might have once caused a wiggle that include “down” no longer does. It takes an even longer cycle, with an even stronger downward bias, to change the upward trend.

    Fortunately for the cause of advancing scientific knowledge, the Sun is providing us with precisely that experiment …

    Comment by FurryCatHerder — 30 May 2010 @ 4:55 PM

  631. John Pollack @ 624:

    There are myriad and sundry ways to reach 300ppm in the next 500 years. But that’s beside the point, which is just that we need to reduce CO2 concentrations in a smart way because we might find ourselves needing to tweak CO2 levels upward in the future.

    In my post-fossil-fuels utopia, I’d like to see the “Carbon Pickup Service” collecting refuse from our homes and return bottled or canned liquid fuels back to us the next week. Could make for interesting ads — “Drive your car on junk-mail and kitchen leftovers!”

    Comment by FurryCatHerder — 30 May 2010 @ 5:01 PM

  632. Ray Ladbury (614), how on earth could the solar guys possibly alter your overwhelming evidence??

    Comment by Rod B — 30 May 2010 @ 5:07 PM

  633. FurryCatHerder (630) — Consider Tung & Camp (2008?). But do note that uses decadal averages smooths out the minor wiggles due to solar cycles; think in terms of centuries.

    Comment by David B. Benson — 30 May 2010 @ 6:03 PM

  634. “What’s the graph of y = mx + b + a * sin(cx)?”

    Not the graph you used earlier.

    PS guard against curve fitting: it only fits if past behaviour is a guide to future behaviour.

    Comment by Completely Fed Up — 30 May 2010 @ 7:22 PM

  635. David Benson @ 632:

    In the words of what’s his face from Back Draft — “You’re doing it wrong”.

    Your approach is to say “No, the sun isn’t affecting climate (because if you use century scales the wiggles all get worked out).” My approach is to say “Right now we’re in a Grand Solar Minimum. That’s a strong cooling bias. That’s why the temperature isn’t setting new records. After SC24 ends, we’ll see plenty of new records, unless we take aggressive action.”

    Think Judo or Hapkido, not Boxing or Thermonuclear Warheads.

    Long term — the trend is up. Right now — sideways. Explain why it’s sideways and sweep their feet out from underneath them.

    Comment by FurryCatHerder — 30 May 2010 @ 7:26 PM

  636. David Benson @ 632 redux:

    Here’s another from Skeptical Science –

    http://www.skepticalscience.com/solar-cycles-global-warming.htm

    Keep in mind — SC24 isn’t an ordinary cycle. We’re going through one of the longest and weakest transitions between solar cycles in a century or so. 2007 and 2008 were two of the four weakest years on record, and 2010 ain’t all that exciting either.

    This is my basis for asserting that solar cycle length / sunspot cycle is creating a very strong cooling bias that will end either with SC24 or SC25 (I’m betting on SC24 since SC23 was already winding down from SC22).

    The Gore Minimum =will= end. Then we =will= resume Global Warming. But right now, we’re sideways and we’re going to stay that way.

    Comment by FurryCatHerder — 30 May 2010 @ 7:40 PM

  637. FCH,
    While there is some evidence of a solar effect on global temperatures, I would not call it tremendously convincing–mainly because there is no known mechanism.

    I am reluctant to invoke a cause–especially one that supports my argument–if I don’t know the mechanism. This is particularly true for a noisy system like climate. That would put us in the same league as the denialists. So, by all means, we must look at this, but
    1)Until we have a mechanism, it ain’t science
    2)it does not in any affect the properties of CO2 as a greenhouse gas.

    As I have said before, a well mixed, long-lived greenhouse gas has left its fingerprints all over the paleo and current climate. The only viable candidate is CO2.

    Comment by Ray Ladbury — 30 May 2010 @ 8:46 PM

  638. Ray @ 636:

    I don’t know that something with a cycle of 200 or so years is going to show up as other than noise in a very long term climate picture.

    I suspect that the reason there is no “mechanism” is more political than scientific. Mechanisms have been proposed, and there is certainly evidence that, for example, the Dalton and Maunder Minima were cooler than the surrounding time periods. Dueling papers have been published, and I’m sure that more papers will be added to the controversy.

    There are a lot of areas of science where the exact reason or mechanism isn’t know, but the evidence is fairly solid. Like, what causes gravity? We don’t know what =actually= causes gravity, but ignoring gravity because you don’t know the precise mechanism isn’t much of a way to do science. So I’m not convinced that failing to nail down the =exact= cause of the relationship between solar cycle length and global temperature means it gets to be ignored.

    Comment by FurryCatHerder — 30 May 2010 @ 9:28 PM

  639. Cat 621,

    Which part of “solar variation only accounts for 2.5% of temperature variation” did you not understand?

    Comment by Barton Paul Levenson — 31 May 2010 @ 5:00 AM

  640. Cat 622,

    The chimera of a nearby ice age is not supported by the facts. Milankovic cycles are celestial mechanics, a very precisely known science. The next stade isn’t for 20,000 years, and it’s so shallow we’ve probably already prevented it. The next deep stade is 50,000 years from now–not 500. No need to save CO2.

    Comment by Barton Paul Levenson — 31 May 2010 @ 5:27 AM

  641. Here are regressions A) of Hadley Centre dT on years since solar minimum, B) years since solar maximum, and C) both. These regressions use the Wolf annual sunspot number to determined peaks and troughs.

    A) dT = -0.170 + 0.00235 SinceMin

    N = 149 (1860-2008)
    R^2 = 0.000847
    Adjusted R^2 = -0.00595
    t on intercept = -4.30 (p < 0.0000305)
    t on coefficient = 0.353 (p < 0.724)

    B) dT = -0.149 – 0.00207 SinceMax

    N = 149
    R^2 = 0.000633
    Adjusted R^2 = -0.00617
    t on intercept = -3.93 (p < 0.000129)
    t on coefficient = -0.305 (p < 0.761)

    C) dT = -0.161 + 0.00190 SinceMin – 0.00146 SinceMax

    N = 149
    R^2 = 0.00113
    Adjusted R^2 = -0.0126
    t on intercept = -2.71 (p < 0.00760)
    t on SinceMin = 0.269 (p < 0.788)
    t on SinceMax = -0.203 (p < 0.839)

    Conclusion: There is not even the smallest hint here of any cyclical effect of Sunspot number on dT. After adjustment for number of variables, no variance is accounted for at all.

    Note: Similar results are obtained with TSI.

    Comment by Barton Paul Levenson — 31 May 2010 @ 6:06 AM

  642. “So I’m not convinced that failing to nail down the =exact= cause of the relationship between solar cycle length and global temperature means it gets to be ignored.”

    Why do you think that the earth’s temperature is causing a longer solar cycle length?

    Comment by Completely Fed — 31 May 2010 @ 6:24 AM

  643. FCH, there is a huge difference between attribution of, say, planetary motion and the putative solar mechanisms. The latter system is quite noisy, and there are many factors that change with the solar cycle. CO2 stands out because it is such a persistent effect. The Milankovic cycles stand out due to their regularity.

    However, the Grand Minimum/Maximum “cycle” is not really periodic so much as oscillatory. Thus, without a mechanism that predicts where to look for a bump in the frequency spectrum, it is very easy to fool yourself with noise. The difference between science and simple empiricism is that the former is empiricism guided by theory. Moreover, none of the mechanisms I’ve heard are particularly compelling.

    Going 12 years without a new record is not all that unusual–Tamino has posted on this. Going 15 years would be odd, but it probably wouldn’t entirely invalidate current models. And finally, the past 12 months have been the warmest on record.

    Comment by Ray Ladbury — 31 May 2010 @ 9:22 AM

  644. CFU @642:

    Magic space zombies?

    It has to be Magic Space Zombies since no one, not even the folks who believe there is a link between solar cycle length and global temperature believe it’s the earth’s atmosphere which has an influence on the sun.

    Comment by FurryCatHerder — 31 May 2010 @ 9:44 AM

  645. BPL @ all of them:

    You can’t linearly regress a cyclical function, much less one that is chaotic.

    Try this — regress hourly temperature and cosine(incidence angle). Taking a naive approach to statistics, you’d have to conclude that “afternoon” causes high temperatures …

    (For even more fun, regress hourly =indoor= temperature on an un-air conditioned building and the cosine of the incidence angle — then you get “sundown” causes high temperatures …)

    Comment by FurryCatHerder — 31 May 2010 @ 10:10 AM

  646. Ray @ 643:

    Yes, it’s easy to be fooled by “noise”, but the probability that “noise” is unrelated to “signal” is reduced each time “noise” and “signal” correspond.

    Unless I missed something, this decade is not like the previous one. In this decade, people argue about how many more years before a new record means it’s “global cooling”. In the last decade, it was pretty obvious. In this decade, the sun is quieter than in a century or more. In the last decade, the sun was at record levels of activity.

    This relationship goes back for millenia — all other things being equal.

    This doesn’t mean that CO2 isn’t the =primary= climate driver at this point in time — point conceded, agreed to, acknowledged, supported, etc. But until you start acknowledging that the giant ball of hot gasses in the sky has gone quiet, and we’re not setting records like we used to, people are going to question your motives.

    Comment by FurryCatHerder — 31 May 2010 @ 11:01 AM

  647. FCH, if you’d point to your sources it’d be easier to figure out what you’re talking about. I can’t match your descriptions with anything I find except stuff from last year.

    Here’s what I find when I look this stuff up. YMMV, but show me please.

    Sun? New cycle starting. http://www.solarcycle24.com/sunspots.htm
    Yes, we haven’t watched enough stars long enough to know what’s expected or if we’re right about the other stars we think are like ours in variability. But ours isn’t quieter than it was last year.

    Temperatures? Much warmer than last year. Click on Ch05 and redraw:
    http://discover.itsc.uah.edu/amsutemps/

    Comment by Hank Roberts — 31 May 2010 @ 11:44 AM

  648. PS, FCH, closest I found to “quieter than in a century or more” was 90 years, as of April 1, 2009 — before the recent uptick:
    http://science.nasa.gov/science-news/science-at-nasa/2009/01apr_deepsolarminimum/
    “We’re experiencing a very deep solar minimum” — Dean Pesnell of the Goddard Space Flight Center.
    “This is the quietest sun we’ve seen in almost a century” — David Hathaway of the Marshall Space Flight Center.

    New instrument will be orbited late this year; here’s Judith Lean:
    http://www.nasa.gov/topics/solarsystem/features/lean-qa.html
    This is attribution: “We think changes in irradiance account for about 10 percent global warming at most.”

    Comment by Hank Roberts — 31 May 2010 @ 12:51 PM

  649. FCH, At this point, I think it is even premature to say that the past cycle was anomalous. Previous cycles in the past century had similar lengths. And although Solar Min usually lasts 4 years, it’s not unusual for it to last as long as six. You have to realize that the heliomagnetic field is not really quite periodic. Rather, like all such dynamos, it loses strength in the dipole with energy going into other modes until the dipole flips and you get a new cycle. It’s more criticality than cyclicity.

    Comment by Ray Ladbury — 31 May 2010 @ 1:44 PM

  650. 600 I like natural gas better. Nuclear waste and a potential meltdown 3 mile island and chernobyl etc…lol have me in ongoing concern. Of course that is Russia. France seems to be handling nuclear energy well, but I am not in support of the US depending upon nuclear reactors more than we alreayd are now.

    Comment by Jacob Mack — 31 May 2010 @ 4:50 PM

  651. “no one, not even the folks who believe there is a link between solar cycle length and global temperature believe it’s the earth’s atmosphere which has an influence on the sun.”

    Then your argument was threaded the wrong way.

    Your version had the effects of earth temperature on the length of this solar cycle as the driving position. Why else is it that you are concerned that the link between cycle length (as opposed to solar output) and global temperatures is being ignored?

    After all, solar output is an INPUT to the global models. This makes it rather hard for a GCM to ignore solar output…

    Comment by Completely Fed Up — 31 May 2010 @ 6:35 PM

  652. David B. Benson

    I have looked at your analysis of decadal temperature changes versus CO2 concentrations based on the Barton Paul Levenson analysis, which you cited. As you state:

    From well understood physics, we suspect the logarithm of CO2 concentrations (lnCO2) explains most of the variation and indeed from a standard correlation
    http://bartonpaullevenson.com/Correlation.html
    this is confirmed. Now we want to explain the GISTEMP global temperature anomaly product (GTA) from the Arrhenius formula which (approximately) explains the warming due to ln(CO2).

    I cannot argue with the mathematics.

    But let’s take a closer look at this analysis. And let’s keep it simple (Occam), without any hypothetical considerations of warming “hidden in the pipeline”, etc.

    The Arrhenius formula explains atmospheric warming due to ln(CO2).

    Let’s see how well this works on a decadal basis, using the 2xCO2 climate sensitivity of 3.2C (mean value of IPCC model simulations), taking the actual observed linear rate of temperature change over each decade and the logarithm of the change in observed CO2 concentration over the period.

    Years prior to 1958 will be difficult to analyze, since there are no physical observations of atmospheric CO2 concentrations prior to the Mauna Loa record, so let us forget these.

    Let us use the HadCRUT temperature record (rather than GISS), since this is the record preferred by IPCC.

    This record shows:

    1958-1967 ln(C2/C1) = 0.0229 dT(theo) = +0.106C dT(act) = -0.163C
    1968-1977 ln(C2/C1) = 0.0329 dT(theo) = +0.152C dT(act) = -0.014C
    1978-1987 ln(C2/C1) = 0.0392 dT(theo) = +0.181C dT(act) = +0.050C
    1988-1997 ln(C2/C1) = 0.0344 dT(theo) = +0.159C dT(act) = +0.127C
    1998-2009 ln(C2/C1) = 0.0619 dT(theo) = +0.286C dT(act) = +0.040C (12 instead of 10 years)

    The correlation is weak (more of a “random walk” than a real correlation), and does not validate the assumed 3.2C climate sensitivity

    If we look at longer periods (breaking the 1958-2009 period into two 26-year periods) we see:

    1958-1983 ln(C2/C1) = 0.0849 dT(theo) = +0.392C dT(act) = +0.195C
    1984-2009 ln(C2/C1) = 0.1249 dT(theo) = +0.596C dT(act) = +0.442C

    Even here, the correlation is weak and does not support the 3.2C climate sensitivity.
    (The first half suggests a CS of 1.6C and the second half a CS of 2.4C).

    So the result obviously depends very much how one analyzes the data.

    Max

    Comment by manacker — 31 May 2010 @ 6:45 PM

  653. Furry 645,

    You’re arguing against a straw man. If solar and temperature are BOTH sinusoidally linked, a linear regression will show high correlation. You specified the length of the cycle might be important. I just did the regression. It isn’t important. It isn’t even there. It’s not the sun. Deal with it.

    Comment by Barton Paul Levenson — 31 May 2010 @ 7:26 PM

  654. Ray @ 649:

    Yes, previous cycles =have= had similar lengths, and other transitions have been similarly slow.

    And when that has happened, there has been a period of cooling in some part of the planet. That we’ve yet to make a new record high on HadCRUT since 1998 — to me — confirms the hypothesis. That’s part of why I made that Live Journal post 2 years ago — I’d been talking about SC24 and why I felt we’d not made a new record high for a few years before that post. So, I’m pretty set on this solar cycle length influences climate thing.

    Unless “random chance” somehow causes these things to just line up. You know, like “random chance” is somehow mostly “right” …

    As for SC23, it was more normal than SC22. SC24, as others have mentioned, is not at all like any we’ve seen in quite a while, and the buildup is still on-going, so it may yet make new records. On the other hand, SC24 is starting to ramp up and the question is how “quiet” does the sun have to be to keep a lid on setting records. My personal stake in the ground is that we won’t see one until 2014. Or rather, that we =will= see one in 2014.

    Comment by FurryCatHerder — 31 May 2010 @ 9:16 PM

  655. max 652: Years prior to 1958 will be difficult to analyze, since there are no physical observations of atmospheric CO2 concentrations prior to the Mauna Loa record,

    BPL: Where in the world did you get that idea? Have you never heard of ice cores? We have a high quality record of carbon dioxide levels for the past 800,000 years.

    Comment by Barton Paul Levenson — 1 Jun 2010 @ 4:39 AM

  656. “And when that has happened, there has been a period of cooling in some part of the planet. That we’ve yet to make a new record high on HadCRUT since 1998 — to me — confirms the hypothesis.”

    This is not a hypothesis that is missing from the GCM models, however.

    What these models don’t do is model the magnetosphere of the sun (much like it doesn’t model when a volcano is going to happen), therefore the prediction in 1992 for the temperature in 2002 would not have included the actual solar constant (nor could it). Just like Hansen’s 1980;’s model had *a* “Pinatubo-strength” volcano but didn’t actually have the real Pinatubo eruption in it.

    And I think that because of the fact that solar input is already included in models yet you’re making a big song-and-dance about it is why Ray is skeptical of your point: there doesn’t seem to be one.

    So where are you going with this?

    Comment by Completely Fed Up — 1 Jun 2010 @ 4:40 AM

  657. Furry 654: I’m pretty set on this solar cycle length influences climate thing.

    BPL: We can see. In the face of all the empirical evidence to the contrary, too.

    Comment by Barton Paul Levenson — 1 Jun 2010 @ 4:40 AM

  658. BPL (655)

    You probably misread what I wrote. I said that there were no physical observations of atmospheric CO2 concentrations prior to the Mauna Loa record.

    Ice core data are not quite the same as actual physical observations.

    Max

    Comment by manacker — 1 Jun 2010 @ 8:09 AM

  659. Max suggests: “And let’s keep it simple (Occam), without any hypothetical considerations of warming “hidden in the pipeline”, etc.”

    Bzzzzzz! Oh, but thank you for playing. Sorry Max, but ignoring warming in the pipeline is unphysical. The upper oceans represent a considerable thermal reservoir that equilibrates on a much longer timescale–e.g. ~30 years. Occam would not have approved. In the search for simplicity, it does not pay to over-simplify.

    Comment by Ray Ladbury — 1 Jun 2010 @ 8:42 AM

  660. Ray Ladbury

    Sorry. The “hidden in the pipeline” postulation has been invalidated by the physical observations.

    The “heat reservoir” was supposed to have been the upper ocean. But the upper ocean has cooled since Argo measurements replaced the inaccurate expendable XBT buoys in 2003.

    At the same time the atmosphere (surface as well as troposphere) has also cooled slightly since 2001.

    The latent heat from melting ice or net water evaporation is too small to make a difference.

    As a result, the “hidden energy” is nowhere to be found in our climate system, so does not exist.

    Kevin Trenberth thinks it may be going back into outer space, with clouds acting as a natural thermostat to reflect more incoming SW radiation.

    See “The Mystery of Global Warming’s Missing Heat”:
    http://www.npr.org/templates/story/story.php?storyId=88520025

    Another postulation has it disappearing into the lower ocean.

    In either case, it is not “lurking in hiding” somewhere to come out and eventually cause more atmospheric warming, as some scientists have postulated.

    And the “hidden in the pipeline” hypothesis has been falsified.

    Occam would definitely have approved of eliminating the somewhat implausible and rather complicated postulation of “energy hidden out of sight”.

    Max

    [Response: Since Max's understanding of this is so low, please do not indulge him in more pointless explanations. He is not going to get the point and this boring and highly repetitive diversion will continue. Enough already. - gavin]

    Comment by manacker — 1 Jun 2010 @ 10:24 AM

  661. BPL @ 657:

    Well, I put that post up so that today I can say “I put that post up years ago and we’ve yet to break the HadCRUT record because I believe in the link between solar cycle length and global temperature”.

    Meanwhile, the “There is no correlation!” crowd scratches its head.

    I have a prediction that held, you have “There is no correlation!” Actually, you have “The correlation between solar cycle length and global temperature diverged in 1975″, which is what the articles I referenced above showed =and= that agrees with what would be seen as man-made CO2 began to dominate the global climate. Except that we’re in a Grand Solar Minimum, so …

    Comment by FurryCatHerder — 1 Jun 2010 @ 10:33 AM

  662. Why just keep going ’round with the guy who denies science works?
    Suggestion: look at the original post again and pursue the topic?

    “… there are plenty of factors that can affect the overall mean temperature (solar variability, volcanoes, greenhouse gases, internal variability etc.) and so it is hard, given the uncertainties in the solar or volcanic reconstructions to precisely attribute the paleo changes in the global or hemispheric mean to these factors. But if we can look at more complex fingerprints of the changes, it might be possible to be more quantitative in those attributions since the spatial fingerprints of the different factors are easier to distinguish. ”

    That’s a challenge right there. Retyping basic science to the guy who just repeats his argument from ignorance is helping him derail the topic.

    “… we can look at more complex fingerprints of the changes … the spatial fingerprints of the different factors are easier to distinguish”

    There must be a lot of scientists each looking at different locations and different fingerprints across locations. If we can talk about the topic, the conversation might attract more scientists.

    Comment by Hank Roberts — 1 Jun 2010 @ 11:24 AM

  663. “Ice core data are not quite the same as actual physical observations.”

    Think through the words you use. Of course, ice core data is an actual physical observation. What else could it be? If you see an ice cube melt you know what the temperature is just as surely as if a column of mercury in a graded tube says so.

    Comment by Jeffrey Davis — 1 Jun 2010 @ 11:33 AM

  664. “I have a prediction that held, you have “There is no correlation!””

    Actually, he has “only 2.5% of the variation is correlated with solar”.

    Comment by Completely Fed Up — 1 Jun 2010 @ 11:39 AM

  665. Jeffrey Davis says: 1 June 2010 at 11:33 AM

    “Ice core data are not quite the same as actual physical observations.”

    Think through the words you use. Of course, ice core data is an actual physical observation.

    No, no! Once the air samples from Mauna Loa etc. are captured they’re no longer observations! The very act of their sequestration changes their composition, somehow. Don’t ask for an explanation of how that happens; the transmogrification part has not quite been figured out yet and is still in the realm of imagination.

    Comment by Doug Bostrom — 1 Jun 2010 @ 11:58 AM

  666. CFU @ 664:

    Go read the referenced posts on Skeptical Science, okay? It’s one of the “Good Guy” blogs.

    Other than “random chance”, do you, personally, have any thoughts on why there’s not been a new HadCRUT record since 1998? Any predictions, projections, hypotheses, ideas, concepts, etc. that you’ve been advocating for, say, 5 or more years?

    There’s a hypothesis — a deeper solar minimum will reverse (or delay increases in) global temperature.

    There’s an experiment — G-d has provided us with a deep solar minimum.

    There’s a result — no new HadCRUT record since 1998.

    Looking at past iterations of this “experiment”, the same result.

    Come up with something besides “Are Not!”, okay?

    Comment by FurryCatHerder — 1 Jun 2010 @ 12:21 PM

  667. “Go read the referenced posts on Skeptical Science, okay? It’s one of the “Good Guy” blogs.”

    That neither changes what BPL said nor what you said he said (which was different).

    “There’s a hypothesis — a deeper solar minimum will reverse (or delay increases in) global temperature.”

    And that hypothesis has no physical basis and (if is part of the GCR scare) has been shown insufficient.

    “There’s an experiment — G-d has provided us with a deep solar minimum.”

    I think you’ll find it’s just the Sun.

    “There’s a result — no new HadCRUT record since 1998.”

    1998 was an extreme El Nino. Are you now purporting that the El Nino is Solar Cycle driven?

    And there’s been a new GISS record, and HadCRUT has a joint top-spot. And indicates that this year is going to be the new top spot.

    “Come up with something besides “Are Not!”, okay?”

    Ah, we’re back on to the “say something the other person didn’t say” schtick.

    2.5% of the variation is accorded by solar changes.

    You’re the one saying “Is not.”. Come up with something.

    Comment by Completely Fed Up — 1 Jun 2010 @ 12:33 PM

  668. Gavin, just don’t let his stuff through. Heck [edit] the whole schmeer out.

    It’s been done before by other moderators who remain anonymous.

    Comment by Completely Fed Up — 1 Jun 2010 @ 12:35 PM

  669. FCH,
    I recommend the following post by Tamino:

    http://tamino.wordpress.com/2009/06/26/breaking-records/

    Be careful when taking records as your metric. Records are inherently in the realm of extreme value statistics, and the tails of the distribution are difficult to pin down.

    Comment by Ray Ladbury — 1 Jun 2010 @ 12:58 PM

  670. Ray # 669 that is a good post by Tamino. I printed that one up.

    Comment by Jacob Mack — 1 Jun 2010 @ 2:42 PM

  671. Ray @ 669:

    Yes, I’m well aware of both the post by Tamino and the perils of using records as a metric. However, since the general direction for temperature is “up”, I feel that records are more than appropriate in this particular case (while still acknowledging that they are prone to their own set of issues), and make a better point.

    That said, I’ve been putting out the same message for quite a while now. It’s not like I decided just last week to hang my hat on solar cycle length. There was even a thread a while back where Lindzen, I think it was, refused to take an even-money wager on which way global temperatures were going. When I said I’d be happy to take the wager, all the sudden people clammed up.

    So, I’m right on the “no new records”, I’ve been at this for a while, and I was willing to put my money where my mouth was. I know this makes me extra annoying, but it’s part of my charm!

    Comment by FurryCatHerder — 1 Jun 2010 @ 3:06 PM

  672. FCH

    You and I may not agree on everything, but I believe you see that arguing with those who already have their minds made up is an uphill battle.

    To agree with you just a tiny little bit shakes up the whole belief system.

    Max

    Comment by manacker — 1 Jun 2010 @ 3:29 PM

  673. FurryCatHerder said: “I said I’d be happy to take the wager,”

    WHat wager is it that you will take?

    Comment by John E. Pearson — 1 Jun 2010 @ 4:53 PM

  674. Max 658: You probably misread what I wrote. I said that there were no physical observations of atmospheric CO2 concentrations prior to the Mauna Loa record.
    Ice core data are not quite the same as actual physical observations.

    BPL: What are they, spiritual observations? Data is data.

    Comment by Barton Paul Levenson — 2 Jun 2010 @ 4:57 AM

  675. furry 666: do you, personally, have any thoughts on why there’s not been a new HadCRUT record since 1998?

    BPL: Because we haven’t yet had another record-breaking El Nino like we did in 1998?

    The fact that there was a brief peak in 1998 is MEANINGLESS. Will you PLEASE crack an introductory stats book? It’s the trend that matters, not one outlier.

    Comment by Barton Paul Levenson — 2 Jun 2010 @ 5:00 AM

  676. Gavin,

    I was going to list the references showing the ocean is warming, not cooling, but after your post I won’t.

    Wouldn’t it be easier on all of us, though, to just kick Max’s annoying butt off the echo? Rather than let him post misinformation we’re not allowed to answer?

    Comment by Barton Paul Levenson — 2 Jun 2010 @ 5:30 AM

  677. “I put that post up years ago and we’ve yet to break the HadCRUT record because I believe in the link between solar cycle length and global temperature”. – FCH

    You think your beliefs have affected global temperatures???

    Comment by Nick Gotts — 2 Jun 2010 @ 7:06 AM

  678. FCH, try the following experiment:

    Flip a coin until it comes up tails. Note the number of times you had to flip it before it came up tails. Now keep flipping until you have a streak that breaks your previous record. Note how many times you had to flip the coin before your record streak started. Repeat many times. This will give you an idea of how things compound as we seek to break ever higher records.

    Now in the case of climate, things are more complicated. Our probability distribution is not stationary. However, to a first approximation, the mean is increasing roughly linearly. The extreme value statistics, though can increase much more quickly than linearly, though. The 1998 El Nino was a really big event–over 2 sigma, as I recall. It’s going to take awhile to break that.

    You can also play around with this in Excel or R. Tamino’s post gives you an idea how to proceed. When looking for patterns, it is very important to assess statistical significance. Our visual cortex is hardwired to see patterns. It’s why we see faces in clouds or why heat rising off of a highway appears as a body of water.

    Comment by Ray Ladbury — 2 Jun 2010 @ 7:55 AM

  679. Nick 677 and BPL 675: shhhhhhhh. Please see 671 & 673. I don’t know whether there’s one born every minute but a fair bet (based on an assumption of no underlying trend and a 1988 temperature nearly 3 sigmas above the mean which would suggest that the 1998 HadCrut record was a roughly once in a hundred years event) strikes me as potentially lucrative.

    Comment by John E. Pearson — 2 Jun 2010 @ 9:05 AM

  680. BPL

    You ask why ice core data on CO2 are not as valid as actual physical measurements for determining the atmospheric concentration for a given year.

    Are you serious?

    (If so, check all the info out there on the reasons.)

    Max

    Comment by manacker — 2 Jun 2010 @ 2:28 PM

  681. BPL

    BTW, I do not challenge the validity of any ice core based CO2 data for telling us (more or less) what the atmospheric CO2 levels were over a composite number of years in the Antarctic or Arctic.

    I just think that the data show that it is stretching the imagination a bit to believe that this will give you an accurate indication of global CO2 concentration for a given year.

    If you believe otherwise, so be it.

    “Belief” is a wonderful thing, BPL.

    Max

    Comment by manacker — 2 Jun 2010 @ 2:33 PM

  682. Re 681 CO2 averaged over x years derived from an ice core record is still good information about CO2 changes on longer time periods. Which is good enough for some important purposes.

    Comment by Patrick 027 — 2 Jun 2010 @ 3:44 PM

  683. … and the physics and ecology suggest that there are limits to the likelihood of large excursions that would not be resolved for x-year averaging…

    … and CO2 is to a good first approximation well-mixed over most of the mass of the atmosphere.

    Comment by Patrick 027 — 2 Jun 2010 @ 3:47 PM

  684. Max Anacker (652) — You analyzed the last 13 decades wrongly and so clearly failed to understand what was in the link I posted for you. In particular, I made no assumption about the transient reponse (OCTR); it is calculated by best fit.

    Go back and study it more carfully.

    Regarding ice core CO2 data, I checked Law Dome against the Keeling curve for the interval of overlap. These agree.

    Comment by David B. Benson — 2 Jun 2010 @ 4:22 PM

  685. Quoted from inline above, for those who missed it and will respect it:

    [Response: Since Max's understanding of this is so low, please do not indulge him in more pointless explanations. He is not going to get the point and this boring and highly repetitive diversion will continue. Enough already. - gavin]

    Comment by Hank Roberts — 2 Jun 2010 @ 4:48 PM

  686. Patrick 027

    You wrote:

    CO2 averaged over x years derived from an ice core record is still good information about CO2 changes on longer time periods. Which is good enough for some important purposes.

    I agree fully. It just isn’t as good as real measurements at the time for establishing the actual CO2 concentration for a particular year (to use for establishing decadal trend correlations between CO2 and temperature, for example), which was my argument.

    Max

    Comment by manacker — 3 Jun 2010 @ 6:21 AM

  687. Let’s just stop answering max altogether. I admit I’ve been a chief offender in this regard. But I think the moderator was right–he’s one of those “bad attention is better than no attention” people. Stop responding and he’ll eventually go away.

    Comment by Barton Paul Levenson — 3 Jun 2010 @ 9:06 AM

  688. re Hank’s note @685, as a “change management leader” mr Anaker doesn’t seem to have changed much in the last 3 years, he’s still following the money.

    Comment by flxible — 3 Jun 2010 @ 9:12 AM

  689. [edit of irrelevant manipulations of data to prove meaningless points. Please stop]

    Comment by manacker — 3 Jun 2010 @ 4:07 PM

  690. Hey, Gavin, it’s your blog, so you can censor out anything that is too inconvenient for you. Congratulations!

    Max

    [Response: Repetitive and irrelevant recitations of the same generic 'Max' talking points in every other comment thread is not 'inconvenient' - it is just tedious. Feel free to assume that my boredom with your tactics equates to my helplessness in front of your brilliance, but good luck trying to convince anyone else. - gavin]

    Comment by manacker — 4 Jun 2010 @ 2:25 PM

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