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  1. Thanks for that. I had wondered if the 1997 Indonesia fires, which put out a huge amount of carbon, had made a large impact on the 1998 anomaly, but with the ENSO adjusted data it doesn’t seem to have had such an impact.

    Comment by George Darroch — 4 Jul 2008 @ 10:36 PM

  2. Is it possible to tease out from the data whether there is a long term change in the ENSO cycle? Can we tell if the frequency or strength of events is changing? Is one phase becoming more common than the other? Or is the length of time of decent data just too short?

    Comment by Thomas — 4 Jul 2008 @ 10:58 PM

  3. This is a wonderful post and much needed in the blogosphere debate with the junk science experts — thanks so much!

    Comment by Tenney Naumer — 4 Jul 2008 @ 11:23 PM

  4. Has anyone looked at trends in other climate/weather parameters besides temperature that might help explain the more rapid than expected decrease in ice cover? For example, wind or ocean current speed and direction.

    Comment by Craig Allen — 5 Jul 2008 @ 12:36 AM

  5. Can you give some idea of the geographical extent of the area warmed by an el nino event?

    Comment by Ian K — 5 Jul 2008 @ 3:00 AM

  6. Looking at the HadCRUT3v ENSO corrected graph,it seems as though the temperature has flattened out since 1998. Could that be due to the melted Arctic ice being flushed into the Atlantic? See:
    http://www.homerdixon.com/download/arctic_flushing.html

    Cheers, Alastair.

    Comment by Alastair McDonald — 5 Jul 2008 @ 4:25 AM

  7. For how long has it been agreed that short term trends are not meaningful?

    When James Hansen went before Congress in 1988 he made a great deal out of what was at that time a short time trend. As can be seen from your graph there had been a slight falling trend in global temperatures between 1950 and 1976. The graph he used had a five year moving average which showed that temperatures had been generally declining during the 36 years 1940 to 1976. But the shortness of the warming period did not stop Hansen explaining to Congress the statistical significance of the rising trend that had occured during the 12 years before 1988.

    [Response: Since always. Hansen did not make his points because of a short-term trend in temperatures but because the long term trends were a match to the expectation he had from the physics. And he was right. - gavin]

    Comment by Patrick Hadley — 5 Jul 2008 @ 6:32 AM

  8. I remain particularly curious with respect to the reinforcing or damping potential of the PDO on ENSO. Only when both are negative for example do we see positive mass balances on Northwest North American Glaciers, as was the case this winter
    http://www.the-cryosphere.net/2/13/2008/tc-2-13-2008.pdf. The forecasting of El Nino has improved amazingly in the last decade http://www.cpc.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf
    Are there any plans to incorporate the Arctic data into the global temperature data sets, or is it too short term to adequately do this?

    Comment by Mauri Pelto — 5 Jul 2008 @ 6:46 AM

  9. … (which as you know has been warming up somewhat) …

    I read the post given at the link (I have not read all the comments). I do not see that the state of the Arctic sea ice has been shown to be dominated by the thermal processes typically associated with increases in the temperature of either the air or water at the North Pole.

    There are several physical processes that can account for a decrease in the mass of ice and its spatial extent at the North Pole. It would be nice to see definitive statements that at least rank the physical causality possibilities, and supporting data, that seem to be at work at this time. Are air and water temperature data at the North Pole available that indicate that these have recently increased? Doesn’t the fact that about 90% of the ice is under water seem to indicate that the water temperature might be more important that the air temperature? Even a list of those that can be eliminated, to the extent possible, would be helpful relative to getting a handle on causality.

    Mother Nature works based on causality conditions at the temporal and spatial locations of interest. Time-series plots summarize the effects, not the dominate physical causality processes at work.

    Thanks

    Comment by Dan Hughes — 5 Jul 2008 @ 8:41 AM

  10. I am not sure how anyone can look at James Hansen’s graph of global temperature history in his 1988 presentation and say that there was a long term warming trend at that time. Look at the five year moving average line on his graph and see that the steep rising trend only began in 1976. His five year moving average trend line appears to be around 0.2 degrees lower in 1976 than it was in 1940.

    Better still, get rid of the (weather and El Nino influenced) short-term five year averaging and show long term climate changes by putting ten and twenty year moving averages on the data. Both those lines are pretty flat for about 20 years until around 1978. Can 20 years of flat temperature trend plus 12 years of increase equal a long term trend?

    [Response: yes. - gavin]

    Comment by Patrick Hadley — 5 Jul 2008 @ 9:16 AM

  11. Gavin, may I please copy this post to my own blog? I get about 2,000 hits per month, now, and the people who look at my blog are looking for just this type of info. Thanks

    [Response: sure - gavin]

    Comment by Tenney Naumer — 5 Jul 2008 @ 9:18 AM

  12. Patrick Hadley, as a reminder, you can put your name +Hansen +trend into a Google Search to review past answers to the same question. People seem to answer it the same way each time you raise it.

    Comment by Hank Roberts — 5 Jul 2008 @ 9:59 AM

  13. What is the underlying cause of El Nino and La Ninas? They have apparently been going on for centuries but why? The amount of energy difference is huge and I don’t think that many people would argue that they don’t have a significant impact on the global temperature in the short run. Why and how does the pacific store up all that energy for an El Nino and then release it?

    I don’t think I am wording this well but hopefully you get my drift (pun partially intended).

    Comment by Sean — 5 Jul 2008 @ 10:29 AM

  14. If you also take out the pinatubo volcano event, it is also clear that the shown trend in the graph given here is a negative acceleration curve. This strikes to me as contradictory to the speech that we are upon a runaway climate change process. I welcome that news. Given peak oil and peak coal to happen in the first middle of this century, I also harbor the probable heretic notion (in here at least) that little changes will be required to be made in the political scene.

    I will refrain to redirect my reply to interesting sites (which I have nothing in common with) that develop this point so that no one will accuse me of trolling around.

    Comment by Luis Dias — 5 Jul 2008 @ 10:50 AM

  15. “You can more clearly see the impacts of the volcanoes (Agung: 1963, El Chichon: 1982, Pinatubo: 1991).”

    It would be interesting to see a similar graph with the effect of the volcanoes removed.

    Comment by Steve Reynolds — 5 Jul 2008 @ 10:53 AM

  16. #6 Alastair, In Canadian slang : nopes… Apparently not, look at NH data
    http://data.giss.nasa.gov/gistemp/tabledata/NH.Ts.txt
    There has been a net warming in the Northern Hemisphere as to compared to the entire globe.
    Warmest year in NH history was 2007, the year of the great melt.
    2008 is in a class of its own, it started with a cooling impact from the lack of clouds in the Canadian side of the Arctic. It would be again good to have global cloud coverage vs temp graphs, I am sure they look a bit the same. Not to say it has any cosmological reasons to be nearly identical, clouds play a big role in surface cooling or warming. Note the key word SURFACE, I have yet to see a DWT
    global graph! Although someone may be working on this. A Density Weighted Temperature plot
    of the entire troposphere makes cloud driven surface temperature variations obsolete, temperature anomalies become far smaller, the Global trends would essentially become less jagged.

    Removing ENSO from the picture is a great idea, and behold, the world is a warming despite it.
    A great Post again, RC is #1 on climate despite annual variations in tempers…

    Comment by wayne davidson — 5 Jul 2008 @ 11:25 AM

  17. it is also clear that the shown trend in the graph given here is a negative acceleration curve.

    The attenuation is due to several well known buffers in place, buffers which are now being actively diminished.

    Comment by Thomas Lee Elifritz — 5 Jul 2008 @ 12:07 PM

  18. I’m confused by a study that tries to subtract out a climate system response that influences a substantial chunk of the Pacific Ocean basin to get at the planet’s “true” temperature response to anthropogenic greenhouse gases. Although I haven’t read the Thompson et al paper, the assumption seems to be that ENSO variability and the global temperature trends related to increasing CO2 levels are unrelated. But how do we know that?

    How do we know, for example, that the 1997-98 warm phase period in the Pacific was not linked to GHG forcing? I’m not a close follower of the literature in this area, but has someone done an attribution study showing that the 97-98 event – or general ENSO variation in the past 30 years – would be unchanged in the absence of increasing anthropogenic GHG forcing?

    Comment by Steve Mauget — 5 Jul 2008 @ 12:57 PM

  19. CO2 levels have increased from about 308 ppm in 1950 to 385 ppm in 2008. It appears that temps have increased by about 0.55C

    Are we able to extrapolate something about the CO2 sensitivity from these figures?

    [Response: No. i) the temperature is not in equilibrium with the forcing (that takes time) and ii) CO2 is not the only forcing - you need to factor in aerosols, other greenhouse gases etc. - gavin]

    Comment by Lowell — 5 Jul 2008 @ 2:21 PM

  20. Steve Mauget (18) — Indirectly peraining to your quexstion, I recommend reading “Earth’s Climate: Past and Future” by W.F. Ruddiman. At a minimum, this will improve your intuitions.

    Comment by David B. Benson — 5 Jul 2008 @ 3:10 PM

  21. I really like the second graph in this article. It looks like temperatures are starting to level off, despite a higher CO2 level and CO2 rate of increase in the atmosphere. Sweet

    [Response: Brought to you by the magic of natural variability... - gavin]

    Comment by Gary P — 5 Jul 2008 @ 3:37 PM

  22. “Brought to you by the magic of natural variability… – gavin]”

    How do we know that recent temperatures are not typical, and that 1950 to 1978 temperatures were not unusually low due to natural variability?

    Could a climate sensitivity of around 1.5C also be consistent with this data?

    Comment by Steve Reynolds — 5 Jul 2008 @ 4:35 PM

  23. #13 Sean
    Gavin

    Has anyone overlaid the 11.1 solar cycle (9-14 yr. avg.) over the El Nino/La Nina cycle?

    I’ve been thinking about what drives the cycle and that thought has popped up in my head several times over the past few years.

    With a .3W/m2 variance that’s a pretty good booster, just wondering it the overlay graph would match up?

    The 1998 was in the upswing of the sunspot cycle activity so I’m curious if this pattern is fairly well repeated and what other complications might be attached to the influence.

    #22 Steve Reynolds

    Natural variability is what it is. You seem to be happy about a leveling off trend even though we are essentially in a cool phase with low sunspot activity and La Nina occurrence. Will you also say “sweet in a few years when sunspot activity is peaking again and we get another El Nino?

    not to oversimplify, but while natural variability occurs, that does not mean that the overall climate system is not operating outside of natural variability when it comes to forcing levels, which are not calculated around 1.9 W/m2 when considered with all the positive and negative forcings (aerosols, moisture, clouds etc.).

    The ’1950 to 1978′ (1942 to 1978) temps were likely due to aerosol pollution. We can always go back to producing sulphates and CFC to cool the planet I suppose, but how much do you like acid rain and skin cancer and all the other wonderful respiratory disorders we gained from that type of pollution? natural variability of course is always at play on top of anthropogenic influence in our modern era.

    Comment by John P. Reisman (The Centrist Party) — 5 Jul 2008 @ 6:26 PM

  24. Steve Reynolds (22) — Using the stand formula for temperature increases due to addional CO2, I compared 1958 CE (315 ppm) with 1850 (288 ppm) and obtained the average temperature increase for the 1850s decade to the 1950s decde, close enough.

    So by this one, kinda crude, measurement: no, climate sensitivity is close to 3 K.

    To see that it cannot be as low as you suggest, read Gregory et al. (2002).

    Comment by David B. Benson — 5 Jul 2008 @ 6:31 PM

  25. Are we able to extrapolate something about the CO2 sensitivity from these figures?

    [Response: No. i) the temperature is not in equilibrium with the forcing (that takes time)...]

    Is there an official figure on the lag? If it’s known you could calculate the sensitivity, right? After looking at the data, it appears that the lag is about 8 years for a fluctuating trend. It would be more for a long-term CO2 increase. It might not even be catching up that way. With an assumption of 8 years, the average effect I see is 0.015 degrees (C) for every extra 1 ppmv CO2 in the atmosphere. The relationship appears to be completely linear.

    Comment by Joseph — 5 Jul 2008 @ 6:54 PM

  26. #12 Hank you are a natural science detective.

    Comment by Mauri Pelto — 5 Jul 2008 @ 6:59 PM

  27. Off Topic: Gavin, I was intrigued by some of the articles in the June 13th issue of Science Magazine. Is there any chance of getting a guest contribution summarizing the state of Dynamic Global Vegetation Models and how they might be incorporated in future GCMs?

    Comment by Jeff — 5 Jul 2008 @ 7:20 PM

  28. David B. Benson: Using the stand formula for temperature increases due to addional CO2, I compared 1958 CE (315 ppm) with 1850 (288 ppm) … climate sensitivity is close to 3 K.

    Any estimate based on that small CO2 change is extremely crude…

    Benson: To see that it cannot be as low as you suggest, read Gregory et al. (2002).

    I looked at Gregory; they also say 1.1K is possible with different assumptions. Also, I wonder what the result would be if their methods were repeated with recent data?

    Another paper showing 1.2K as possible:
    http://www.jamstec.go.jp/frcgc/research/d5/jdannan/prob.pdf

    Comment by Steve Reynolds — 5 Jul 2008 @ 7:21 PM

  29. #25 Joseph

    I am not an expert but I do have two cents to throw in. The forcing is at 1.9W/m2 so it will take more than 8 years for the oceans to absorb the forcing. Of course as they absorb the forcing, they will release more moisture. There is apparently a great amount of learning still in the cards on clouds but this is a pretty big forcing. I’m not expecting things to cool down anytime soon.

    More moisture means positive feedback. There has been a 4 degree latitudinal shift, which i believe was expected of the jet stream system. I’m a pilot, so I relate that to how we measure air density. Hot air expands, so when we try to get our aircraft of the ground, if it’s hot, it’s harder to get enough air over the wing to produce enough lift.

    As things heat up, I would therefore expect that hotter air will create less dense air and that said, air expansion would push the jet streams north and south as the tropics get more sunlight and the heat is trapped in the climate system, and absorbed slowly by the oceans.

    That will have an effect on the geometric absorption of heat I suppose, relational to the amount of GHG’s at a given time and the amount of earth absorbing the solar radiation.

    So with the increase of heat trapping gases and the positive feedback of increased water moisture, which is of course also a greenhouse gas, in the atmosphere. I’m just expecting things to get warmer, which in turn will make things warmer.
    i.e. positive feedback.

    I doubt any 8 year trend is significant to ocean absorption lag time.

    Gavin already pointed out that you have to add the aerosols and other gases, then you have to consider effects.

    The amount of time for the lag absorption rate is also relational to the type of gas doing the forcing. While Methane and Nitrous oxide gases are more short lived, Co2 is long lived in the atmosphere, so stopping some of the gases will not eliminate the long term forcing on the oceanic thermal absorption. The lifespan of atmospheric Co2 is pretty long, retaining still 25% over hundreds of years.

    So lag time has to be understood in connection to the type of GHG and the lifetime of the GHG. Add em all up and you can start to draw a picture.

    Comment by John P. Reisman (The Centrist Party) — 5 Jul 2008 @ 7:40 PM

  30. Are we able to extrapolate something about the CO2 sensitivity from these figures?

    [Response: No. i) the temperature is not in equilibrium with the forcing (that takes time)…]

    So where is the missing temperature? I presume some form of lag via the oceans. However the ocean temperatures are not recently rising (the ARGO data set), and a strong and consistent trend should be observable with consistent CO2 increase. Is this correct?

    regards, sdw

    Comment by sdw — 5 Jul 2008 @ 8:45 PM

  31. #23.
    “The ‘1950 to 1978′ (1942 to 1978) temps were likely due to aerosol pollution. We can always go back to producing sulphates and CFC to cool the planet I suppose, but how much do you like acid rain and skin cancer and all the other wonderful respiratory disorders we gained from that type of pollution? natural variability of course is always at play on top of anthropogenic influence in our modern era.”

    Look at the waxing and waning of the solar cycles. Solar cycle #20 was relatively low and long. Is it just coincicdence that a cooling period occured during cycle 20? Is it a coincidence that the Dalton Minimum during solar cycles 5 and 6 produced notably cool temperatures? Is it a coincidence that temperatures are starting to go down after a relative long solar minimum between cycles 23 and 24? What about the little ice age durning the Maunder solar minimum in the mid to late 1600′s? Why attribute it to aerosols when a direct relationship between weak solar activity and cooler temperature can be seen. It could be just a coincidence but sure looks good to a layman such as myself. The people posting here are a lot brighter than I am. I just cant let go of solar/climate connection. There are some smart people like the fellow who heads up one of Russia’s space related agencies, Habibullah Abdusamatov.
    He strongly beleives that it is the sun that is the primary driver of climate. I was directed by a knowledgable poster to check out the discrediting of solar cycle influence on climate. I did so and was almost swayed to that opinion. But I still have a lingering though unfounded suspicion that variations in the solar output should be given more higher weight in the climate models. We are now in a pretty deep solar minimum. Temperatures have start to fall this year. There may be a significant lag between solar min and consequential global temp decrease. If the solar minimum continues and temperatures continue to drop then the influence of solar cycles should be given more consideration. If the minimum continues and temperatures continue to rise then I will abandon the idea that climate follow solar activity. It will take only one or two years to convince me of that.

    Comment by iceman — 5 Jul 2008 @ 9:02 PM

  32. #23 John P. Reisman

    Okay, I type too fast, my apologies.

    “which are not calculated around 1.9 W/m2″

    is supposed to be

    which are ‘now’ calculated around 1.9 W/m2

    Comment by John P. Reisman (The Centrist Party) — 5 Jul 2008 @ 9:07 PM

  33. Could it be that PDO and AMO are subharmonics of solar forcing?

    A post from solarcycle24.com:

    Hansen predicted in 1988 that we would be considerably warmer now than we are. That’s a fact.

    The past decade, at the very least, has not seem the same rate of warming as the previous two decades (all natural variability such as ENSO accounted for). Also a fact.

    NASA predicted in 2006 that if an El Nino formed later that year, or in 2007, a new global temperature record “would almost surely” be set. The El Nino formed, but neither 2006 or 2007 came close to 1998. The 2007 IPCC report states that they expect half the years from 2009-2015 to be warmer than 1998.

    It is clear that “climate science” expected, and still expects, more warming than what has been observed. None of this “oh, natural variation and cool spells are expected to interrupt the warming (for more than a year or two)” crap…that’s not what has been predicted, and if temperatures do not rebound in a big way soon, AGW projections will continue to look foolish.

    Comment by iceman — 5 Jul 2008 @ 9:54 PM

  34. #33, Iceman: do a graph of Northern Hemisphere annual temperature anomalies
    from here:

    http://data.giss.nasa.gov/gistemp/tabledata/NH.Ts.txt

    Is my understanding that CO2 has far greater impact overland than sea. But the facts speak about a noticeable warming.

    Comment by wayne davidson — 5 Jul 2008 @ 10:27 PM

  35. that’s not what has been predicted, and if temperatures do not rebound in a big way soon, AGW projections will continue to look foolish.

    Why? There are plenty of places for that heat to go. I can think of three of them offhand, besides the obvious.

    The portals in and out of these places are very fluid.

    Comment by Thomas Lee Elifritz — 5 Jul 2008 @ 10:34 PM

  36. #31 iceman

    Climate is not driven only by solar though. Some of what you are saying may be or likely is coincidence. As is known correlation is not necessarily causation. Cherry picking data and narrowly scoping the view does not help either. That was the UAH problem and it led them to eventually be proven wrong in their base assumptions because they did not look at the big picture. That was also the problem illustrated in the Great global warming swindled movie, where they represented only the data that matches and stopped the data set where it no longer matched because it did not suit their purpose of trying to trick people in to believing something that was not true.

    Apples and oranges are not the same but both are tasty. The Maunder minimum is natural cycle/variability. But you have to look at variability and geologic time scale in relation to the forcing components.

    As far as the sun being the primary driver of climate, absolutely. if you take the sun away, we would not have climate to be concerned about, nor would we be here. I am oversimplifying with a purpose.

    Climate is driven now by components of natural variability and human components added to the forcing of the climate. We are actually quite far outside of natural variability on the recent trend. There has thus far been no model or even substantive reasoning that can explain this recent warming.

    Only looking at solar is cherry picking too though. DOn’t forget there are lots of things actin on climate. Eccentricity, Precession, Obliquity. Oceans and algae (co2 absorption) methane, nitrous oxide. co2 High GWP’s albedo changes cloud pattern shifts moisture content etc.

    From what is currently known, if we were following natural variability, we should be cooling more. But we are not. So something changes. The

    If I were to follow your logic, then when we should have been warming during the 40s and 50s because solar cycle 17, 18 and 19 were each progressively stronger. But at that time we were producing a lot of sulphates and other aerosols that helped cool the planet but that is also complimented by natural variability.

    It is too easy to oversimplify or cherry pick your data and reasons for climate. When everything is looked at in context and with relevance to the forcing added and taken away and placed in the context of natural variability, then the picture not only becomes clearer, it matches the models quite well.

    Comment by John P. Reisman (The Centrist Party) — 5 Jul 2008 @ 10:44 PM

  37. #33 iceman

    Cool down iceman, your starting to warm.

    I don’t know about your “fact” about Hansens prediction. The 1988 model when revisited in 2006 was pretty much on track in scenario B which was presented as the most likely scenario.

    Here are some facts, the long term trend is up, and there is more warming in the pipeline. There is no reason to expect a trend reversal (unless you have some new data and modeling you would like to share (that has made it through peer review and peer response and survived)) to to the amount of forcing in the system, the lifetime of Co2 in the atmosphere, the human industrial output and the oceanic thermal inertia and lag time for absorption. AGW projections are not foolish, they are science, and extremely well founded, not to mention that little consensus thing among relevant climatologists that are working in the field on a daily basis.

    Comment by John P. Reisman (The Centrist Party) — 5 Jul 2008 @ 10:52 PM

  38. Re: #33 (Iceman)

    … neither 2006 or 2007 came close to 1998.

    According to GISS analysis, 2007 tied 1998. That’s not close enough for you? You’re the one looking foolish.

    Comment by tamino — 5 Jul 2008 @ 11:25 PM

  39. the el nino that preceeded 1998 was much stronger and longer than the el nino that preceeded 2007.

    just summing up the monthly ENSO values prior to 1998 and prior to 2007 i get +22.2 for 1998 and +5.2 for 2007 (approximating an area-under-the-curve to try to gauge the magnitude of the whole event).

    http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml

    also, unless my eyeballs are deciving me (i’m staring at monthly NASA data which is a lot of numbers), Jan 2007 was the warmest (by temperature anomoly) month ever, and Dec/Jan/Feb around that month was the warmest 3 month period.

    http://data.giss.nasa.gov/gistemp/tabledata/GLB.Ts+dSST.txt

    so we’re almost there. a little larger of an el nino or a few more years of AGW and the 1998 record should be soundly broken.

    Comment by Lamont — 6 Jul 2008 @ 12:01 AM

  40. Iceman,

    Every year since 2000 have been warmer than any year prior to 1998. I don’t see how that squares with you assertion that AGW projections look foolish.

    I gather you have at hand some kind of statistical analysis that demonstrates your subharmonic of the solar forcing theory. Lets see it then. Some details about the mechanism would be of interest also.

    Can you point to any temperature predictions made in 1988, which were based on the assumption that there is no CO2 induced warming, that were more accurate than Hansen’s prediction?

    Comment by Craig Allen — 6 Jul 2008 @ 1:01 AM

  41. None of this “oh, natural variation and cool spells are expected to interrupt the warming (for more than a year or two)” crap…that’s not what has been predicted.

    Please reveal the sources in which climate scientists have proclaimed that AGW will put an end to natural variability.

    It’s the first I’ve heard of it …

    Comment by dhogaza — 6 Jul 2008 @ 3:28 AM

  42. Curious how this correction wasn’t found necessary for particularly warm years. One imagines there was some great advance in the mathematics involved.

    [Response: Don't imagine. Try reading instead (umm.. 1998?). - gavin]

    Comment by peterg — 6 Jul 2008 @ 4:10 AM

  43. Re #33, there are still large error bars in temperature rises due to soot, black carbon and aerosoles and hence temperature rise predictions are cautionary in nature. The big factor remains that GHG theory when modelled up to AGW theory takes notice of the Arctic and in the Arctic AGW is seemingly correct.

    Comment by pete best — 6 Jul 2008 @ 4:51 AM

  44. Re #28
    “David B. Benson: Using the stand formula for temperature increases due to addional CO2, I compared 1958 CE (315 ppm) with 1850 (288 ppm) … climate sensitivity is close to 3 K.

    Any estimate based on that small CO2 change is extremely crude…”

    Why then did you ask about 1950-1978? That’s, ooh, 29 years. cf 109 years David used.

    iceman at 31, do the calculations and see if the changes in solar output explain the MAGNITUDE of the change.

    I find it odd that when the small forcing of CO2 is brought up people say it’s a miniscule change, even though the trend is there, but when someone says it’s the Sun, even though that is a miniscule change, they see the trend immediately.

    Is that purely because one is their fault and the other not, so seeing a change is acceptable in one and not the other?

    Comment by mark — 6 Jul 2008 @ 5:02 AM

  45. iceman writes:

    It is clear that “climate science” expected, and still expects, more warming than what has been observed. None of this “oh, natural variation and cool spells are expected to interrupt the warming (for more than a year or two)” crap…that’s not what has been predicted, and if temperatures do not rebound in a big way soon, AGW projections will continue to look foolish.

    iceman, the World Meteorological Organization (WMO) defines climate as “mean regional or global weather over a period of 30 years or more.” Do you suppose they just picked that figure out of the air? A few years of apparent cooling don’t really mean much, especially when you’re starting with the hugest El Nino on record (1997-1998) and ending with the largest La Nina in 20 years (2007-2008).

    Comment by Barton Paul Levenson — 6 Jul 2008 @ 6:23 AM

  46. @33
    “Hansen predicted in 1988 that we would be considerably warmer now than we are. That’s a fact.”

    That’s not a fact. It was discussed in length. It was a false accusation from a guy called Crichton. That is how false accusations turn into so called “facts”. Solar influence on climate is discussed in the IPCC report.

    Concerning the Russian guy, he should publish his findings. They will be reviewd and discussed. About the litte ice age: Well, in 1600 global satellite technology was not exactly as good as nowdays and precise weather data from Africa or South America for this period ist hard to obtain. If there was such a thing, it was most likely not caused by aerosols.

    Comment by PeterK — 6 Jul 2008 @ 6:39 AM

  47. Concerning the Russian guy, he should publish his findings. They will be reviewd and discussed. About the litte ice age: Well, in 1600 global satellite technology was not exactly as good as nowdays and precise weather data from Africa or South America for this period ist hard to obtain. If there was such a thing, it was most likely not caused by aerosols.

    I’m unclear on the “If there was such a thing” comment. I know there is a strong tendency of most pro-global-warming posters here to ignore that giant ball of fire and its cyclical behavior, but on what planet does ignoring the Dalton and Maunder Minimums make sense? And when the Gore Minimum brings another short term cooling trend, how do you propose explaining that so people understand the difference between short term cooling, long term warming, and the need to do something?

    Comment by FurryCatHerder — 6 Jul 2008 @ 8:01 AM

  48. Fair enough, he published a little bit on the Pulkovo site. There are some documents in English (or they have an English abstract), most of it is in Russian (I do not speak Russian), but you get an idea what he wants to say. He needs to be taken into consideration, because he is in charge of some important experiments on the ISS. I think that the theories presented on his site are not well founded. If somebody speaks Russian, a translation would be helpful. Just google for Pulkovo, Laboratory of space research. Why are they not well founded?

    Quote from the site:

    “A year ago, many meteorologists predicted that higher levels of carbon dioxide in the atmosphere would make the year 2007 the hottest in the last decade, but, fortunately, these predictions did not become reality. Hence, increase of carbon dioxide concentration in the atmosphere is not the cause of global warming which has a solar origin and is a part of natural two-century cycle”

    This was discussed over and over. We are talking about long term trends. His conclusion that one year (2007) falsifies the AGW theory is – let’s call it a bit strange. And there is no clear evidence presented for his assumed “two-century” cycle.

    Comment by PeterK — 6 Jul 2008 @ 8:23 AM

  49. He strongly beleives that it is the sun that is the primary driver of climate.

    The data suggests otherwise.

    Comment by Joseph — 6 Jul 2008 @ 8:41 AM

  50. Re #48

    It even gets the cart before the horse.

    This could still explain:

    2007 would be 2.0 degrees warmer because of CO2. A normal El Nino would have cooled by 1.0 degrees. It would have been 1.0 degrees warmer. This would be a maximum.

    However, a strong El Nino would have cooled by 3.0 degrees. Therefore, 2007 with a strong El Nino (which could not be forcast at that time) was 1.0 degrees cooler.

    And there’s a huge logical jump there to say that just because 2007 wasn’t the warmest, that CO2 can’t cause global warming. I mean, did it before then, but the universe noticed that 2007 *wasn’t* warm and change the physics???

    Comment by Mark — 6 Jul 2008 @ 8:43 AM

  51. Is the ENSO being impacted by GW? I’d sort of think that more warming might lead to longer and stronger ENSO, but I don’t know.

    Or is ENSO figured based on its relativity to the current and shifting “norm” and not some absolute temps?

    Comment by Lynn Vincentnathan — 6 Jul 2008 @ 8:45 AM

  52. @47

    Sorry for the overlap,

    that is not the case, it is not ignored, but because of a lack of data, we do not kow, how these events worked out in different parts of the world. What is understood though is the basic physics and we know that in increase in Greenhouse gases drives temperatures up. This is what you call a fact. The Russian chap does not deny this fact (like many sceptics do) but he states that decreased radiation from the sun will ultimatly be a stronger factor. Okay, great, now it’s up to him to prove it and his theory mus be analysed with the same rigorous scrutiny, which ist applied to the AGW theory. At Pulkovo, they sould have the resources to develop a model to Open Source it and then be open for a reality check.

    Comment by PeterK — 6 Jul 2008 @ 9:08 AM

  53. Can someone run a fourier transform on the solar cycle data starting from 1610 until now? Maybe there would be a hint of ~30 year PDO/AMO cycle embedded in the results. Perhaps PDO/AMO is like an amplitude modulated signal riding on the 11 year solar cycle carier signal.

    Okay. I am almost ready to concede that solar influence is less than I naivly thought. I am new to this stuff and thought that I had all the answers. I like being a contrarian. But there seems to be a change in tone from AGW proponents. Articles I have seen in the media a few years ago proclaimed that over the past 30 years Co2 from fossil fuel use has totally swamped natural variability. I think the standard AGW claim is that CO2 influence is a factor of 10 greater than that of natural variability. Now since the strong la nina AGW proponents are saying that natural variability can mask AGW. I had not heard that a la nina could dampen global temperatures until after the fact. At least that is what I have picked up on from following media stories on the subject.

    Comment by iceman — 6 Jul 2008 @ 9:13 AM

  54. Peterk.
    The sun may prove the russian wrong or right in the near future. This current long solar minimum was unexpected. Dr. David Hathaway of NASA, one of the foremost authoriities on solar cycles was predicting a strong cycle 24 that should of started two years ago. Now the solar scientists who had predicted a weak cycle 24 seem to have the stronger position. There may be no need to wait decades to completely trash the russians ideas. Solar influence on climate is seriously being put to the test right now. Solar activity is low. At its current rate solar cycle 24 wont reach peak for 3 or 4 years. It is quite exciting actually. In the next 5 years if there is not a downward trend in temps then the russian should be banished to siberia. A good web site to check solar activity is : solarcycle24.com. It is run by a HAM radio operator. The HAMMIES are besides themselves with frustration. They need strong solar activity in order top have better propagation of their signals.

    Comment by iceman — 6 Jul 2008 @ 9:29 AM

  55. Peter,

    The people who will decide to act are not climate scientists.

    The Denialists fall into a few loosely constructed categories.

    My category is the “we’ll go broke before we burn all the carbon fuels needed to boil the oceans” one, and I’m fairly confident that I’m more correct than the IPCC business-as-usual forecasts, and I’d argue that the current economic upheaval over oil prices bears that out. My particular form of denialism isn’t dangerous because it advocates a massive shift to renewable energy forms to avert an economic disaster which will also avert an environmental one. Based on that, I’m a relatively harmless crackpot.

    But the folks who are going to latch on to the Gore Minimum and use it to “prove” that CO2 is not a problem are the ones that have to be reached, and remarks like

    This was discussed over and over. We are talking about long term trends. His conclusion that one year (2007) falsifies the AGW theory is – let’s call it a bit strange. And there is no clear evidence presented for his assumed “two-century” cycle.

    fly in the face of what I understand to be well-established science. What are you going to say when the sun stays spot free for a while longer and the well-established relationship between a spot-free sun and lower global temperatures begins to contradict your remarks? When year after year, there are no new global high records, what do you say?

    Comment by FurryCatHerder — 6 Jul 2008 @ 9:29 AM

  56. It is interesting to watch supporters of AGW defend their position. Science is real, climate is real. How is it real (relating to the article) to take away what is happening to show what one believes should be happening? A simple proposed hypothesis: “as global atmospheric CO2 levels rise, so will global atmospheric temperature”, is not happening. Why? Because the observed “real climate” does not agree with that proposed hypothesis.

    In “real science”, this is a primary reason to question the proposed hypothesis.

    I would also note that if we accept the definition of climate as “mean regional or global weather over a period of 30 years or more”, then shouldn’t we be using the 30 year period 1978 through 2008? Would not, then, the last 10 years be a full third of the entire period? Why is the time between 1998 to 2008 considered too short a period to be valid? I believe the answer is clear: the last 10 years do not fit the proposed hypothesis, therefore they must be rationalized away in some manner.

    If the AGW by CO2 emission proposed hypothesis is correct, the raw data and observation should show it clearly. Not predictive models, not “what if” scenarios, not manipulated figures – raw data and observation.

    So far, they do not.

    [Response: Your point illustrates very clearly why 'armchair science' has more in common with armchairs than science. First off, your supposition that increasing CO2 leads to more warming is fine as a general principle but in any actual application you have to caveat it with 'all else being equal' and an appreciation of the signal to noise ratio in any finite time series. That means that if something else is going on - a big volcano for instance - you need to consider those changes too. But the biggest issue is one of signal vs noise. There is more CO2 in the air today than this time last year - yet do you expect that extra 2ppm to translate to a measurable 0.02 deg C change in the global mean temperature? No. The standard deviation from one year to another in these records is between 0.1 and 0.2 deg C - therefore the year to year variation will swamp the expected change. After 30 years, the single will be clear (as indeed it is) since the expected change (~0.5 deg C) is larger than the variability. If you take shorter periods the signal to noise ratio goes down - how is this controversial? We build models to quantify these expectations more precisely and for the recent period, the models show a range of behaviours (while all showing a long term trend) which easily span the observed behaviour. In order to falsify a proposition you need to show that the result is in fact outside of the expected range of behaviour. Does the fact that is cooler today than yesterday imply that summer is now over? - gavin]

    Comment by Person of Interest — 6 Jul 2008 @ 9:33 AM

  57. Steve Reynolds, The question is not whether a low climate sensitivity is consistent with any one particular set of data, but which sensitivity is most consistent with all the data. This is a much more powerful constraint. The thing is when you look at only one dataset, yes, you see that low values of sensitivity may be possible–but you also can’t eliminate 6 degrees per doubling, and that would be catastrophic. Personally, I would be much more satisfied if we could reduce the probability that sensitivity is >4.5 degrees per doubling than if we could raise the probability that it’s less than 2 degrees per doubling. That makes the problem much more manageable from the point of view of risk management.

    Comment by Ray Ladbury — 6 Jul 2008 @ 9:35 AM

  58. In re 53:

    Now since the strong la nina AGW proponents are saying that natural variability can mask AGW. I had not heard that a la nina could dampen global temperatures until after the fact. At least that is what I have picked up on from following media stories on the subject.

    If you look at all the published charts, it’s obvious that there are natural variations that can overwhelm the upward trend due to CO2.

    What you see in the media is a focus on a small number of components of the larger situation. Yes, there are natural variations, and yes, sometimes the natural variation overwhelms something else, such as the changes caused by rising CO2 levels.

    So the “natural variations” folks emphasize “natural variations” and ignore “rising CO2 levels”, while the other side does the opposite. Or put another way, the proof of the “hockey stick” isn’t the part that hits the puck, it’s the handle. If, as folks like myself argue, the puck-hitting-part is dominated by strong solar cycles 22 and 23, you still have to deal with the rise in global temperatures from before that. And if cycles 24 and possibly 25 are below normal, someone has to explain “natural variability” so that declines in either absolute temperature or rate of increase don’t serve to discredit the overall “increases in CO2 level cause increases in global temperature”.

    Comment by FurryCatHerder — 6 Jul 2008 @ 9:43 AM

  59. #47 FurryCatHerder

    The giant ball has some behavior and its over 8 billion years old so its hard to understand what its behavior over time is. We know with more surety the 11.1 year cycle, beyond that it turns more into a fuzzy ball. Of course there is the luminosity increase but that is truly minuscule in forcing amount on small time scales such as the warming recently understood in the earth climate (since the beginning of the industrial age).

    What is the Gore Minimum? Do you have relevant data on this? Never heard of it before. Okay, I just googled it. It looks like some people want to call the next solar activity minimum the Gore minimum or the Hansen minimum as a way to ridicule them. Let’s try to stick to the facts of the science and what can be understood from that.

    Just for fun, let’s postulate what would happen to our warming trend if the sunspot activity died. Please for give my gross oversimplification.

    If we have no sunspot activity we lose .3 W/m2 of forcing.

    The current forcing is calculated around 1.9 W/m2

    1.9 – .3 = 1.6 W/m2

    Well, looks like we will still warm. As mentioned previously, there is a lot of extra forcing in the system and it will take time for the ocean to absorb the energy and give us a new equilibrium to forcing ration/balance.

    Why don’t we call the next extended solar minimum the ‘I wish it were cooler minimum’. That might be more appropriate.

    Comment by John P. Reisman (The Centrist Party) — 6 Jul 2008 @ 9:47 AM

  60. Also running the solar cycle data through a low pass filter could unearth some trends that could hint at PDO/AMO.

    Comment by iceman — 6 Jul 2008 @ 9:48 AM

  61. PeterK,
    Did Creighton produce this graph. Just eyeballing it looks like B (the “likely” one) is off by .25 to .3, about half the trend from 1880-1988.

    [Response: Brought to you by the magic of natural variability… - gavin]

    So if someone were to say,

    “Just to make things clear: we are not stating that anthropogenic climate change won’t be as bad as previously thought”…“What we are saying is that on top of the warming trend there is a long-periodic oscillation that will probably lead to a to a lower temperature increase than we would expect from the current trend during the next years”

    Would that be considered reasonable? Or is that the kind of statement which,

    … could backfire against the whole climate science community if the forecast turns out to be wrong.

    I note Gavin, that you did not sign onto this, and precisely because you did not add your name, I would value your viewpoint.

    Comment by Ellis — 6 Jul 2008 @ 9:48 AM

  62. Gavin: The ENSO Corrected data set you provided has an outlier in the “GISTEMP (ENSO Corrected)” data at 1928.88. The value reads 7.229e-0. Please advise if that should end with -01 or -02, as opposed to -0.

    [Response: fixed. It should have read e-05. - gavin]

    Also, a step change exists in HADSST data about the time of the 97/98 El Nino. If you aren’t aware of it, here are two illustrations:
    http://i28.tinypic.com/2ronf9w.jpg
    http://i25.tinypic.com/2cpp2z4.jpg

    That step change is normally evident in any comparison of HADSST or HadCRUT data with another data set: GISTEMP, NCDC, or the two satellite versions, and, obviously, ERSST.v2 and ERSST.v3. It is visible in the longer-term graph above, but disappears in the short-term illustration. How’d you make it disappear? Just curious.

    [Response: Nothing was done, the monthly data are as is. - gavin]

    Comment by Bob Tisdale — 6 Jul 2008 @ 10:14 AM

  63. I had not heard that a la nina could dampen global temperatures until after the fact. At least that is what I have picked up on from following media stories on the subject.

    Which is related how, exactly, to what climate scientists have to say about it?

    Comment by dhogaza — 6 Jul 2008 @ 10:23 AM

  64. #53 iceman

    I doubt any good climatologist would ignore natural variability but you have to recognize context and keep it in your head. Then put what you hear in context of that. Natural variability will not go away, but certain forcing components will drive us in another direction.

    Think of it this way (I am not advocating drinking and driving) Let’s say you drink to much and start driving toward home. Your car is wavering due to the slow response time caused by increased alcohol in your bloodstream impairing judgment. You correct and get back toward the lane but you over correct, which leads to another correction to try to stay on the road. In this example, you are on the road and heading in the direction you should be, but the car is weaving a bit. That is you staying within natural variability (you have not hit a tree, or another car yet) in the expected direction based on the fact you are on the right road.

    Now let’s look at AGW and drunk driving. Let’s say you are fairly well impaired? And you accidentally get on the wrong road? Now you are going in a new direction. But you are still doing the same wavering you were doing before. Just on a different road.

    In other words, you changed course and are no longer going where you expected at the start of the trip i.e. destination home… now you are going somewhere else but you are still wavering on the path (natural variability, warming and cooling short term trends in the new long term trend).

    Natural variability wont go away, it will just be doing its thing on a new road.

    Comment by John P. Reisman (The Centrist Party) — 6 Jul 2008 @ 10:24 AM

  65. Iceman,

    A statistician who goes by the name of Tamino has done the Fourier analysis in exquisite detail here. Not a hint of any kind of periodicity in the temperature record, let alone anything that correlates with sun activity.

    I wouldn’t rely too much store on what media articles tell you about the science. The dodginess of media reporting is a regular topic of conversation here at RealClimate and at many other sites devoted to climate science.

    Comment by Craig Allen — 6 Jul 2008 @ 10:37 AM

  66. In #53 iceman wrote “But there seems to be a change in tone from AGW proponents. Articles I have seen in the media….”

    The key phrase, iceman, is “in the media.” The popular media very often are just plain wrong. Even scientifically literate popular media often overstate the scientists’ claims, in order to make succinct, catchy headlines, in order to attract readers. And scientists themselves often make statements to the media, that are incorrect when interpreted without the context that is in the scientists’ heads and in the scientific literature.

    Comment by Tom Dayton — 6 Jul 2008 @ 10:41 AM

  67. #53 iceman

    One piece of advice. Don’t listen to the media and expect to get science. Their job is controversy, because controversy sells. Another reason not to listen to the media is the Monsanto/Fox news case which made it to the supreme court in Florida. They basically said it is not illegal for the news to lie. So if they do they can’t be prosecuted. Isn’t that lovely.

    #54 John P. Reisman

    correction: new equilibrium to forcing ration/balance

    is supposed to be

    new equilibrium to forcing ‘ratio’/balance

    Comment by John P. Reisman (The Centrist Party) — 6 Jul 2008 @ 10:49 AM

  68. “I know there is a strong tendency of most pro-global-warming posters here to ignore that giant ball of fire and its cyclical behavior”

    Its not that its being ignored. It is, in fact, the first and most obvious thing to look at when discussing climate change. Which is why it has been studied for a couple of centuries, for the history:

    http://www.aip.org/history/climate/solar.htm

    None of this speculation is new, and all of it has been addressed. Yes, climate scientists looked at the rising temperatures since 1880, the cooling around 1940 and the subsequent warming and attempted to correlate those patterns with solar patterns. No, that doesn’t work to explain the current warming.

    Please if you’re going to speculate about solar activity affecting the earth’s climate, address the existing scientific record so that we know that you’ve done your homework. Most of you are just posting nothing more than “have you ever thought about the sun, huh, have you?”. Yes, its been done.

    Comment by Lamont — 6 Jul 2008 @ 11:02 AM

  69. “At least that is what I have picked up on from following media stories on the subject.”

    Stop following the media stories, try following the science.

    Comment by Lamont — 6 Jul 2008 @ 11:04 AM

  70. Re: #53 (iceman)

    First, I (and many others) have been all over the sunspot data and there’s no hint of a cycle near 30 years. Second, the figure 30 years for the PDO/AMO is *not* a cycle — it’s a “characteristic time scale.” There’s no evidence that PDO and AMO are periodic, or even nearly so.

    Probably much of your confusion originates from misinformation you’ve received. For example, you say “I think the standard AGW claim is that CO2 influence is a factor of 10 greater than that of natural variability.” Where did you get this, and precisely what does it mean?

    Comment by tamino — 6 Jul 2008 @ 11:10 AM

  71. > Thompson et al (2008) paper (discussed here), used a neat way to extract the ENSO
    > signal from the SST data, by building a simple physical model for how the tropical
    > Pacific anomalies affect the mean. He kindly used the same approach for the
    > HadCRUT3v data … and I [Gavin] adapted it for the GISTEMP data as well.

    Writing as I always do from the peanut gallery, a Thank You to Dr. Thompson — and I’m curious what more the researchers have to say about the method and where else it may be useful. Is it possible to generalize and describe this as a statistical tool?

    Comment by Hank Roberts — 6 Jul 2008 @ 11:23 AM

  72. Hey. I appreciate the feedback. Kind of flattered that you all are taking the time to respond to my layman naive observations.

    Comment by iceman — 6 Jul 2008 @ 11:28 AM

  73. > “… Articles I have seen in the media….”

    Cite them so you can tell others exactly what you’re talking about and people can read them for themselves instead of trust your recollection.
    Look at the writer’s record. Look at the sources the writer gives (if any). Look at the papers, the footnotes, and then click the ‘cited by’ and the ‘similar’ links available online for most contemporary science paper abstracts.

    You can take one PR press release reported by a handful of media sources and commented on fifty times by five regular blogfloggers, and think something’s happened.

    Trust the source, Luke. But verify.

    Comment by Hank Roberts — 6 Jul 2008 @ 11:29 AM

  74. Iceman #53,

    “Can someone run a Fourier transform…”

    I’m a beginner too (my first serious look at the RealClimate site). On a similar topic, for fun, I did the FFT for global temperature (several incarnations) and sunspots (one incarnation) On that limited basis, there seemed to be a connection between global temperature and sunspot numbers.

    Seeing a connection, I created a fairly straight forward model of global temperature vs sunspots, etcetera. It incorporated limited unsubstantiated assumptions (based on general physics and my reading of the blogosphere literature) regarding mechanisms. It did not include CO2 effects (as I wanted to see if sun alone could explain things, to a first order). The model “fit” the HadCrut2 data quite well from 1880 to present (with about 0.2C left to explain during the last 10 years). The fit to HadCrut3 was not as good from 1860 to present (leaving 0.3C). Looking at areas of misfit, volcanoes, El Nino, etc seemed to be affecting those areas.

    Interesting, but no more than that (if I did it, it can’t be new news).

    I remain open minded regarding the relative importance of sun and anthropogenic mechanisms to global temperatures over the next 100 years.

    Comment by Allen — 6 Jul 2008 @ 11:31 AM

  75. I think I am going stop posting and just read. To quote “The Rock”, “Know your role and shut your mouth”.
    My role is learn more and not waste peoples time til I find out more about the subject. Really glad I stumbled onto this site.

    Comment by iceman — 6 Jul 2008 @ 11:33 AM

  76. Hmmm. I see my #71 findings contradict #64 (which was written as I posted) — no harm intended. Bottom line, in a topic as controversial as this one, I am slow to submit to authority (on either side) :) Rather, I like to try these things for myself when I can.

    Comment by Allen — 6 Jul 2008 @ 11:41 AM

  77. Climate change comes to California? Or “just” La Niña, need to worry?

    The ripple effect
    The state’s water crisis is taking a withering toll on life on the Valley’s west side.
    By Dennis Pollock and Robert Rodriguez / The Fresno Bee
    07/05/08 21:48:39

    Life on the Valley’s west side may be withering along with crops that farmers have left to die.

    Hundreds of farmworkers already have lost their jobs as growers idled or abandoned crops because of severe water shortages. Hundreds more will lose work because of crops that won’t be planted this autumn.

    Signs of trouble are everywhere:

    The Spreckels Sugar plant in Mendota, a fixture since 1963, will close in September unless a grower cooperative can salvage it. Closure would mean 200 jobs lost.

    Fordel, a major grower-packer-shipper of melons and other produce, is selling its Mendota facility after more than two decades. It is not harvesting or packing a crop this year. City officials say the company accounted for as many as 500 growing and packing jobs.

    St. Joseph’s School in Firebaugh is closing this month after more than 40 years, a casualty of declining enrollment and a shrinking pool of farmers able to give money.

    Weather and pest challenges, along with abandoned acreage, are cutting processing-tomato production for Fresno County, the state’s top grower, by as much as 400,000 tons. In 2006, the last year for which figures are available, farmers in Fresno County produced 4.4 million tons of processing tomatoes valued at $248 million. This year’s cut will mean shorter hours of plant operation and less work for truckers.

    Thousands of acres of cotton are being abandoned at a time when planted upland cotton acreage already was at its lowest level on record. In addition, windy weather and roller-coaster temperatures have taken their toll.

    Comment by Jim Galasyn — 6 Jul 2008 @ 11:45 AM

  78. Gavin mentioned and linked to the Arctic Buoy program in the original post. The linked article from 2000 led me to the home page
    http://iabp.apl.washington.edu/index.html
    Their 2008 annual meeting (late June) draft agenda includes:

    –Much faster ice drift speed observed in recent years [T. Kikuchi]
    –State of the Arctic Ocean 2007 [J. Richter-Menge]
    –Treatment of sea ice in the global 1/4° Mercator Ocean
    forecasting system [G. Garric]
    –Outlook for Summer Sea Ice Extent 2008 [I. Rigor]

    Google Scholar recommended to find work already published, there’s a whole lot. The agenda promises more to be found or yet to appear.

    Comment by Hank Roberts — 6 Jul 2008 @ 11:45 AM

  79. I don’t like bets. Would one bet on the view of one Russian institute that solar activity will decrease. As many readers pointed out, the sun is a huge gasball in the solar system and we do not know too much about its behaviour. The logical conclusion is to continue with our current beahviour and place a bet that a decrease in sun radiation will compensate for this (Irony). Brilliant idea. We do not understand our planet but we will instead predict the behaviour of a star. That’s like a stone age man who refuses to learn to light a fire and starts directly with the construction of a nuclear reactor. Good luck to him.

    Comment by PeterK — 6 Jul 2008 @ 11:48 AM

  80. Ray: The thing is when you look at only one dataset, yes, you see that low values of sensitivity may be possible–but you also can’t eliminate 6 degrees per doubling, and that would be catastrophic.

    Annan (2008) seems to do a pretty good job of eliminating sensitivity >3.6C with one data set (and a reasonable prior), although more data sets would add to the confidence.

    Ray: Personally, I would be much more satisfied if we could reduce the probability that sensitivity is >4.5 degrees per doubling than if we could raise the probability that it’s less than 2 degrees per doubling.

    Yes, but even better to show 1.5C the most likely sensitivity and 3C the maximum.

    Comment by Steve Reynolds — 6 Jul 2008 @ 11:53 AM

  81. How is it real (relating to the article) to take away what is happening to show what one believes should be happening?

    That strikes me as a perfectly valid analysis, similar to a “standardization” method of control for confounding.

    Comment by Joseph — 6 Jul 2008 @ 12:21 PM

  82. Mauri Pelto #26:

    #12 Hank you are a natural science detective.

    Given the nature of the subject studied — the practice of posting across various forums lies thinly disguised as “questions” — my characterization would rather be “forensic sleuth”. Or perhaps “natural forensic sleuth”… Hank is a natural. Every teacher knows this technique for catching student plagiarism :-)

    Comment by Martin Vermeer — 6 Jul 2008 @ 12:37 PM

  83. Hi Iceman,

    I know what HAM is, I run a self compiled Linux system. Yes, the debate about solar cycles is interesting and tamino performed a great job. Thanks 64 for the link and tamino for his comment.

    Maybe, I can unterstand you better, because I am a former sceptic and it needs a lot of reading and the willingness to accept that there are open questions. It was only this Blog, not the mainstream media, which finally convinced me. It is not helpful to talk about denialists because it is important for the scientific process that people stand up, get involved and raise valid questions, that’s what we call a democracy.

    @tamino

    What do you think about the Russian stuff and his ideas about solar cycles (e.g. 200 years)? I mean, this guy is not an idiot, even, if I have problems to find a relevant link to climate science, it does not mean that everything from this guy is pure crap.

    Major thanks go to Gavin and the RC-team, this is by far one of the best blogs.

    Comment by PeterK — 6 Jul 2008 @ 12:44 PM

  84. Steve Reynolds, Actually, moving the most likely value from 3 down to 1.5, while still leaving substantial probability for levels above 4.5 really doesn’t help us all that much in terms of risk mitigation–that’s been my point all through such discussions. First, if we reach a point where natural ghg emissions (from oceans, permafrost, etc.) ever swamped anthropogenic emissions, then we’re screwed regardless of sensitivity.
    Second, looking at it in terms of risk, the consequences of high sensitivity are so catastrophic that they dominate risk even for pretty modest probabilities. James Annan’s Bayesian approach is not unreasonable, but the choice of location for the Prior is highly subjective–and not at all conservative. It may give us a warm fuzzy, but I wouldn’t drive a car over a bridge that used similar techniques.
    Finally, many of the same changes that must occur due to climate change must also occur as a result of Peak Oil. Certianly, limitations of energy supply will require decreased consumption in the near term. We will have to come up with different energy solutions. The main difference is that climate concerns force us to leave carbon where it is–sequestered in the ground as coal, tar sands, oil shale, etc., in the Oceans as clathrates and so on.

    At this point, arguments for doing nothing are very difficult to justify.

    Comment by Ray Ladbury — 6 Jul 2008 @ 2:21 PM

  85. Steve Reynolds (28) — Naturally one has to consider as much data as possible and even then one still cannot rule out very low or very high climate sensitivites entirely by these probablistic techniques. Another method is to look at the climate sensitvites of the various GCMs; for this see IPCC AR4 WG1 report. So far, using as much as one can find, climate sensitivity of 3 +- 0.2 K seems the best estimate. Wider error bars cannot be excluded, of course.

    iceman & PeterK — I used a periodogram technique for finding quasi-periodic signals in the temperature anomalies of the GISP2 ice core temperature proxies by Alley, but just for the Holocene. There is nothing detectable by this method for intervals from 22 to 45 years and again from 90 to 300 years. Between 45 and 90 years there seems to be something which could be attributed to the various ocean oscillations. It would, I think, take a wavelet technique to tease out if there is actually anything there; I’m not up on how to do that, so I’ll take a pass on doing anything further with this.

    Comment by David B. Benson — 6 Jul 2008 @ 2:28 PM

  86. @85

    Thank you for your work

    and I would doubt that any anomalies existed.

    However, in his article on his website Abdusamatov makes such a claim. I do not know, if the magazine is good enough and if would be seen as peer reviewed. Generally (and I am a former sceptic) this guy causes us a lot of trouble. In our forum in Germany we now have close to 9.000 postings, so really any comment or any article from Gavin, Raypierre or Stefan on Pulkovo would help. I am still open minded don’t get me wrong, if the Rusian guy would be correct, no problem, but I doubt it.

    Comment by PeterK — 6 Jul 2008 @ 3:52 PM

  87. #36 John P. Reisman

    My apologies to all. I think my fingers are superseding my brain today. Another correction to my own posting.

    There has thus far been no model or even substantive reasoning that can explain this recent warming.

    should include

    ; other than the current GCM’s that include known quantities of industrial based GHG’s and forcings.

    #75 iceman

    “Welcome, to the ‘real’ world.” as Morpheus would say. The science is the science, there are plenty of questions to be answered, but what we do know with confidence is strong enough to base policy decisions on. Unfortunately that means individuals need to understand the science. Because individuals drive politicians, they don’t lead much theses days, they pretty much follow. I would not wait for them to figure it out on their own.

    Comment by John P. Reisman (The Centrist Party) — 6 Jul 2008 @ 4:09 PM

  88. for all those doing FFT analysis on the solar data and the global temperature data it would do well to consult the archives:

    http://www.realclimate.org/index.php/archives/2005/07/the-lure-of-solar-forcing/

    “The potential for self-delusion is significantly enhanced by the fact that climate data generally does have a lot of signal in the decadal band (say between 9 and 15 years). This variability relates to the incidence of volcanic eruptions, ENSO cycles, the Pacific Decadal Oscillation (PDO) etc. as well as potentially the solar cycle. So another neat trick to convince yourself that you found a solar-climate link is to use a very narrow band pass filter centered around 11 years, to match the rough periodicity of the sun spot cycle, and then show that your 11 year cycle in the data matches the sun spot cycle. Often these correlations mysteriously change phase with time, which is usually described as evidence of the non-linearity of the climate system, but in fact is the expected behaviour when there is no actual coherence. Even if the phase relationship is stable, the amount of variance explained in the original record is usually extremely small.”

    And for more links in the archives:

    http://www.realclimate.org/index.php/archives/2004/12/index/#Solar

    Comment by Lamont — 6 Jul 2008 @ 4:46 PM

  89. In #51, Lynn asks-”Is the ENSO being impacted by GW?”

    I wondered the same thing and a cursory search indicates that the jury is still out on this.
    http://www-pcmdi.llnl.gov/projects/cmip/cmip_subprojects/Sun2/sun_proposal2.pdf
    Different models show different responses to global warming at this site.

    Another site expressing uncertainty is:
    http://www.pmel.noaa.gov/tao/elnino/faq.html#coriolis
    (see number 18.)

    Since progress has been made in understanding how ENSO affects surface temps can understanding of the other side of the coin be far behind?

    Comment by Lawrence Brown — 6 Jul 2008 @ 5:21 PM

  90. Ray: James Annan’s Bayesian approach is not unreasonable, but the choice of location for the Prior is highly subjective–and not at all conservative.

    I think Annan would disagree about it not being conservative. Do any real experts have an opinion on this?

    Ray: Finally, many of the same changes that must occur due to climate change must also occur as a result of Peak Oil. Certianly, limitations of energy supply will require decreased consumption in the near term.

    That seems doubtful to me. Price increases will limit oil consumption growth, but the Chinese and Indians seem likely to continue their energy growth with pretty much unlimited coal.

    Longer term solutions involving nuclear and efficient renewables seem more practical to me than trying to convince people to accept a low standard of living.

    Comment by Steve Reynolds — 6 Jul 2008 @ 6:36 PM

  91. David B. Benson: Another method is to look at the climate sensitvites of the various GCMs…So far, using as much as one can find, climate sensitivity of 3 +- 0.2 K seems the best estimate.

    I have still not seen any convincing evidence that GCMs provide reliable physics based estimates of climate sensitivity.

    I don’t know where you got those error bars; if you could prove them reliable, it would make Ray happy.

    Comment by Steve Reynolds — 6 Jul 2008 @ 6:51 PM

  92. A couple of words about our star. Upcomment, someone misstated its age as 8By, the correct figure is pretty close to 4.6By (probably a bit lower, as the age of the earth is now pinned down to 4.57By). If the sun were 8By old, the oceans would have already boiled and our planet would be devoid of life.

    Another statement was made to the effect that we don’t understand the earth, how could we hope to understand the sun. The implications is that the physics of the sun (or of the solar magnetic cycle), are very much tougher than of the earth. I would think just the opposite is true. The solar cycle can be is a result of a convecting plasma in a differentially rotated star. The only difficulty is in working out the relevant MHD equations. Admittedly this is a difficult problem, and it hasn’t and won’t receive the same level of resources as the earths climate system, precisely because the odds of it having a large effect on the earth are deemed a lot smaller than the combination of natural variability and anthropgenic effects on the climate. In any case the relative difficulty of different problems in science cannot be so causally determined.

    Comment by Thomas — 6 Jul 2008 @ 7:12 PM

  93. Steve Reynolds (90 & 91) — The Annan/Hargreave Bayesian priors can be done in an ‘objective’ manner by using maximum entropy methods to determine the prior distribution. One is allowed to use all known physics excluding only the observations which are going to inform the posterior distribution. To be sure that information is not used twice, once in forming the prior and once in forming the posterior, a conservative approach is to use only that physics which was known before the observations were taken.

    In the simplest case, the normal distribution is appropriate; use a corrected Arrhenius approach to determine a mean and variance for the climate sensitivity. (Some may object that this gives nonzero probabilities to negative climate sensitivities.)

    The evidence is that the GCMs, being based on physics, model climate and paleoclimate rather well. I have no idea what else you require?

    I’ve seen ‘most likely estimates’ ranging from 2.8 to 3.2 K; around 3 K. I’m not claiming tight error bars for this. Anyway, not just yet.

    Comment by David B. Benson — 6 Jul 2008 @ 7:20 PM

  94. Steve, the whole point of the GCMs is that they are based on physics, and if the models work better with a value of 3, that is evidence of a sort as long as the physics is not wildly off. We think the physics is right, but if it is wrong, it’s as likely to be wrong in the direction that makes things worse as that which decreases concern. The error bars are probably a standard deviation of the model results, right Dave?

    Comment by Ray Ladbury — 6 Jul 2008 @ 7:40 PM

  95. Steve, Coal is not as versatile as petroleum–so changes in infrastructure will be needed globally. It is a question of whether we take the opportunity to push them away from fossil fuels or whether we replace one addiction with another.

    Comment by Ray Ladbury — 6 Jul 2008 @ 7:42 PM

  96. “Another statement was made to the effect that we don’t understand the earth, how could we hope to understand the sun. The implications is that the physics of the sun (or of the solar magnetic cycle), are very much tougher than of the earth. I would think just the opposite is true. The solar cycle can be is a result of a convecting plasma in a differentially rotated star. The only difficulty is in working out the relevant MHD equations. Admittedly this is a difficult problem, and it hasn’t and won’t receive the same level of resources as the earths climate system, precisely because the odds of it having a large effect on the earth are deemed a lot smaller than the combination of natural variability and anthropgenic effects on the climate. In any case the relative difficulty of different problems in science cannot be so causally determined.”

    Having actually taken an undergraduate level course in stellar models and interiors, it is a little more complicated than that, but generally you are correct that its easier to understand the sun than it is to understand a global climate model for the Earth. With the sun we can also observe that other ~1.0 solar mass stars tend to not be highly variable, and it is a relatively easy problem (compared to other global climate measurements) to measure the suns output which is the important input quantity. Coming from at least an undergraduate background in astrophysics, I’m not at all surprised that the Sun is not the most important factor in global climate variability.

    Everyone trying to look for patterns in solar variability and climate change should also probably broaden their horizons and look at the Milankovich cycles and the Ice ages. Over the past million years we can probably set upper limits on how much intrinsic variability there could have been in the solar output by looking at the magnitude of the variability of the solar forcing due to the orbital changes in the earth and how those caused the Ice Ages. If you perturb the intrinsic solar output too much you would destroy that relationship and in the extreme you would not have a stable, cold Earth and would melt the poles if you included too much variability.

    Comment by Lamont — 6 Jul 2008 @ 8:34 PM

  97. #92 Thomas

    Thanks for the correction.

    Comment by John P. Reisman (The Centrist Party) — 6 Jul 2008 @ 8:46 PM

  98. Iceman, don’t worry, you are not the only lay person here! I’m no scientist either, but from what I (think that I) understand of the scientific arguments, the AGW thesis is, unfortunately for all of us unless we do something quickly, strongly supported. But RealClimate is always a great place to visit for a read: informative and somethimes also provocative articles, great range of responses, interesting pesonalities in the discussion and debate, very useful references, and even the insults are reasonably polite and often funny.

    Comment by Paul Harris — 6 Jul 2008 @ 9:22 PM

  99. Gavin, maybe you can explain how you adapted the procedures that Thompson et al used to correct HadCRUT3v, to correct GISTEMP instead. So far it seems to me that Thomson et al proved that, without the El Niños in 2002, 2005 and 2007, there has been cooling since 2000. I have serious doubts that the methods they used to extract the ENSO signal are valid, but I have even more doubts about yours because you didn’t even describe them. You just say “I did the same and look”. I am not sure that you corrected the Arctic data, which is included in GISTEMP but not in HadCREUT3v, for example. If you didn’t, then you didn’t follow the same procedures.

    [Response: The method is described in the Thompson et al paper (see the "methods" section). I just applied the same delta's from Thompson's analysis of HadCRUT3v (which is not what used in the paper) to GISTEMP - nothing fancy. But if you want to see what other methods would show, read the Fawcett paper linked above. - gavin]

    Comment by Nylo — 7 Jul 2008 @ 1:59 AM

  100. Ray in #94, well said.

    There are meteorologists who don’t believe AGW because they don’t believe in computer models full stop. They maintain that since models are wrong, there’s nothing to worry about.

    They don’t think that they are assuming without any evidence or reasoning that the errors will be on the side of “We’re A-OK!” rather than on the side of “Ohshitoshit we’re all gonna die!”.

    Needless to say, some of them don’t seem to understand the difference between climate forcing and weather prediction.

    The incidence of this outside a community that *ought* to know better makes the public a little less oddball, but bodes less well for humanity’s intelligence overall.

    Comment by Mark — 7 Jul 2008 @ 4:27 AM

  101. Thomas says, “The only difficulty is in working out the relevant MHD equations.”

    Do you realize how many plasma physicists’ heads you just made spin 1080 degrees with that statement? The real question is how well the dynamics need to be understood to reporduce the relevant physics.

    Comment by Ray Ladbury — 7 Jul 2008 @ 4:32 AM

  102. In using the FFT to compare global temperature oscillations to sunspot number oscillations, I found that some temperature data sets showed stronger correspondence than others.

    Using long term temperature data from a single measurement station (virtually raw data) gave a strong temperature-sun relationship (in the few cases I tried).

    Using data “averages” from many stations reduced the correspondence.

    GISS and HadCRUT3 “data” is apparently heavily averaged. I have read that GISS “raw” station data contains over 20 percent interpolations (i.e. over 20 percent of the data points are effectively “made up”). Then, each point from each temperature station is corrected by making a “weighted average” with points from nearby stations (depending on their distance — sometimes up to 1200km). Then, data from all stations is combined using weighting factors to get global temperatures.

    By the time one gets to the final sequence of GISS Temperature vs Month or Year (that we see published), one is dealing with an average of an average of an average … to put it simplistically. I have not read about the HadCRUT3 methodology; but, I assume it has similarities.

    Anyhow, I question the validity of FFT analysis of the final GISS and HadCRUT3 temperature anomaly products — because they have been so “averaged” as to be suspect for that purpose. I would expect such “data” to show less correspondence with sunspots than raw data would show.

    As a beginner in climate science (but not in science), I will continue to study these issues with an open mind.

    Nice site. I have it bookmarked.

    Comment by Allen — 7 Jul 2008 @ 6:03 AM

  103. FurryCatHerder writes:

    I know there is a strong tendency of most pro-global-warming posters here to ignore that giant ball of fire and its cyclical behavior, but on what planet does ignoring the Dalton and Maunder Minimums make sense?

    It doesn’t, they undoubtedly had an effect. But the sun is not driving the present global warming because there has been no clear trend in sunlight for 50 years.

    Comment by Barton Paul Levenson — 7 Jul 2008 @ 7:32 AM

  104. Here is how we know ten years of climate data are not significant:

    Year Anom Slope p
    1988 0.180 0.020 0.000 *
    1989 0.103 0.021 0.000 *
    1990 0.254 0.020 0.000 *
    1991 0.212 0.023 0.000 *
    1992 0.061 0.025 0.000 *
    1993 0.105 0.022 0.002 *
    1994 0.171 0.019 0.011 *
    1995 0.275 0.016 0.044 *
    1996 0.137 0.016 0.092
    1997 0.351 0.007 0.424
    1998 0.546 0.005 0.643
    1999 0.296 0.017 0.084
    2000 0.270 0.012 0.279
    2001 0.409 -0.003 0.618
    2002 0.464 -0.012 0.095
    2003 0.473 -0.017 0.116
    2004 0.447 -0.020 0.270
    2005 0.482 -0.040 0.179
    2006 0.422 -0.020 0.000 **
    2007 0.402

    The first column is the year, the second column is the Hadley Centre temperature anomaly. The column labeled “slope” gives the coefficient of the time term (K yr-1) of a regression starting with the year on the left and ending with 2007. The p column measures significance — p

    Comment by Barton Paul Levenson — 7 Jul 2008 @ 7:49 AM

  105. Why not continue the job and “filter out” PDO, NAO and, while we are at it, AMO etc. etc. This complete removal of “natural variability” (as if it were observation noise) would surely give us an unbiased estimate of the “global warming trend”, or would it……….?

    [Response: ENSO is relatively easy to characterise and the result is pretty insensitive to the details. For these other patterns, there is more ambiguity. The other way to do it is to take the full spatial patterns and do an EOF analysis (or similar) - the first or second mode is likely to be ENSO related, and the other one is a trend and other modes will pop out further down. - gavin]

    Comment by Nonlinear guy — 7 Jul 2008 @ 8:49 AM

  106. David B. Benson: The evidence is that the GCMs, being based on physics, model climate and paleoclimate rather well. I have no idea what else you require?

    I would like to see this evidence that models just based on known physics ‘model climate and paleoclimate rather well’. My understanding is that the accuracy of fit to data depends on a number of adjustable parameters, especially to get the key feedback effects of water vapor and clouds.

    [Response: Your understanding is faulty. Models are compared primarily to the current climatology and all of the adjusting goes into getting the mean climate/seasonal cycle etc. correct. The response of that model to volcanic forcings, the last ice age, changes in orbital parameters etc. are all 'out-of-sample' tests that are not fixed by adjusting parameters. You can show quite easily that without water-vapour feedbacks (for instance), you cannot get a good match to volcanic forcings and responses in the real world (Soden et al, 2005), or to ENSO, or to the long term trends. Cloud responses are more uncertain and that feeds in to the uncertainty in overall climate sensitivity - but the range in the AR4 models (2.1 to 4.5 deg C for 2xCO2) can't yet be constrained by paleo-climate results which have their own uncertainties. - gavin]

    Comment by Steve Reynolds — 7 Jul 2008 @ 9:07 AM

  107. I note that one of the strongest El Nino years appears to be 1878.

    The 1878 average temp appears to be higher, in fact, than the current temp (although probably less than 1998.)

    According to HadCRUT3, the 1878 anomaly peaked at +0.364C versus the current May 2008 anomaly of +0.278C.

    To assess variability, one needs to go farther back than just the last 11 years, or the last 58 years (1950 was actually a very cold period with 1944 being very close to 2008 temps) or even the last 100 years (1878 was warmer than today).

    http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/monthly

    Comment by Lowell — 7 Jul 2008 @ 9:25 AM

  108. Regardless of the method(s) employed, this “linear” filtering approach still seems a little bit odd to me, as if we are trying to empty the AC power spectrum (killing the modes which probably all interact/teleconnect), in search of the “DC gain”, where actually without these modes (dynamics of Mother Earth) the gain itself wouldn’t even exist (“the mean is meaningless”).

    Comment by Nonlinear guy — 7 Jul 2008 @ 9:44 AM

  109. #107 Lowell

    I’m not sure what you are trying to say? You are discussing a peak anomaly in 1878 vs. current may anomaly of .278C.

    You know what they say… anomalies happen. But then you go on to say that “1878 was warmer than today”?

    The Met Office Hadley Centers site (where you picked your piece of data) does not agree with your statement

    http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/

    GMT is a big picture. Is there any reason behind your representation? Or, in other words, why are you saying that 1878 was warmer than today? Or are you referring to a more limited scope analysis not related to global mean temperature?

    Comment by John P. Reisman (The Centrist Party) — 7 Jul 2008 @ 11:01 AM

  110. #102 Allen:

    “I have read that GISS “raw” station data contains over 20 percent interpolations (i.e. over 20 percent of the data points are effectively “made up”). Then, each point from each temperature station is corrected by making a “weighted average” with points from nearby stations (depending on their distance — sometimes up to 1200km). Then, data from all stations is combined using weighting factors to get global temperatures.”

    I’m curious to know where you read that?

    Comment by Doug Bostrom — 7 Jul 2008 @ 11:54 AM

  111. Couldn’t ENSO be thought of as a heat transporter? I have not seen evidence that an ENSO oscillation significantly changes the heat absorption or radiation of the earth. So the heat in an EL Nino had to come from somewhere, and the reduction in heat of an La Nina has to be balanced by an increase in heat elsewhere.

    If so shouldn’t ENSO oscillations be reflected in geography or time by declines or increases in heat energy elsewhere? Presumably a perfect “global average temperature” would reflect this.

    Or am I overlooking something?

    [Response: Not really. ENSO changes the cloud cover and water vapour amounts and so you would expect it to affect the Top-of-the-atmosphere radiation balance which changes the overall amount of heat in the system. Indeed, some of the radiation measurements support this. You also need to think about the net heat flux into the ocean (but that is less constrained). - gavin]

    Comment by John Lederer — 7 Jul 2008 @ 1:00 PM

  112. Ray Ladbury (94) — I believe that IPCC AR4 states a range for climate sensitivity of 2–4.5 K (66%) with 3 K most likely. So there the error bars are -1 K and +1.5 K. Annan & Hargreaves give a means to narrow this range somewhat and I think they give 2.8 K as most likely.

    And so it goes. Narrowing the error bars is actually going to be quite, quite difficult. The best I can think of is to do a corrected version of Arrhenius’s technique, using known physics up through 1977 CE to establish a estimated mean and variance. I’ve been informed that the estimated mean will be around 3 K. Then use the Annan & Hargreaves Bayesian method, with good observations conducted post 1977 CE to sharpen to the posterior. Worth doing, but not by me.

    Comment by David B. Benson — 7 Jul 2008 @ 1:09 PM

  113. Lowell said

    The 1878 average temp appears to be higher, in fact, than the current temp (although probably less than 1998.)

    According to HadCRUT3, the 1878 anomaly peaked at +0.364C versus the current May 2008 anomaly of +0.278C.

    The annual mean for 1878 was 0.023 in a very strong El Nino phase and the 5-month average for 2008 in a La Nina phase is currently 0.241.

    1878 0.155 0.364 0.293 0.309 -0.117 -0.010 -0.053 -0.044 -0.022 -0.120 -0.138 -0.335
    Av. = 0.023

    2008 0.053 0.192 0.430 0.254 0.278 0.000 0.000 0.000 0.000 0.000 0.000 0.000
    Av. = 0.241

    And the
    1877/8 June-May Av. = 0.1
    2007/8 June-May Av. is 0.3

    Comment by P. Lewis — 7 Jul 2008 @ 1:58 PM

  114. Re #107 Lowell:

    (1878 was warmer than today).

    Joking right?

    The extreme for 1878, for Feb, was 0.364, higher than May 2008 (0.278), but lower than March 2008 (0.430). And 2008 isn’t over yet. Also lower than Jan 2007 (0.632) and a heck of a lot lower than Feb 1998 (0.749).

    Comment by Martin Vermeer — 7 Jul 2008 @ 2:00 PM

  115. #102 Allen:

    Using long term temperature data from a single measurement station (virtually raw data) gave a strong temperature-sun relationship (in the few cases I tried).

    Using data “averages” from many stations reduced the correspondence.

    That’s a red flag: the noisier the data, the better the correspondence… I suggest you try your method on generated random data with realistic statistics :-)

    About the reductions/averagings applied to met stations, you’re sort-of right but also confused. The GIStemp site contains some good articles by Hansen et al. on this. Also Tamino’s site contains at least one excellent post on this. I have studied the GIStemp method and understand it, so can you. You owe it to yourself if you seriously suspect that “making things up” is part of the game…

    Comment by Martin Vermeer — 7 Jul 2008 @ 2:15 PM

  116. gavin: You can show quite easily that without water-vapour feedbacks (for instance), you cannot get a good match to volcanic forcings and responses in the real world (Soden et al, 2005)…

    Thanks, the Soden paper is very interesting and I agree shows modeled water vapor effects consistent with real data.

    But this evidence still shows models are not based solely on known physics; they are at least adjusted based on climatology data that has its own accuracy limitations.

    [Response: Not really. Soden did not adjust his model based on this comparison. But of course data is used to build the models in general. How could it not be? - gavin]

    Comment by Steve Reynolds — 7 Jul 2008 @ 3:12 PM

  117. You also need to think about the net heat flux into the ocean (but that is less constrained). – gavin]

    That is actually what bothers me about adjusting for El Nino or La Nina.

    In each case heat is “borrowed from” or “lent to” the subsurface ocean. Presumably there is some slower process by which the heat is brought back into some sort of equilibrium of geography and thermocline.

    If we compensate for the relatively rapid heat transfer of an El Nino but not for the slower return to equilibrium, aren’t we likely to see a climate picture that is unduly influenced by those gradual returns to “normal”? They will be read as “climate trend” while the rapid transfers of an ENSO event will be read as an “unusual” event to be compensated for.

    Comment by John Lederer — 7 Jul 2008 @ 4:29 PM

  118. Steve Reynolds (116) — You may care to read “Estimating Climate Sensitivity: Report of a Workshop (2003)”:

    http://books.nap.edu/openbook.php?record_id=10787&page=7

    Comment by David B. Benson — 7 Jul 2008 @ 4:47 PM

  119. Would it be possible to filter out the AGW signal and show us the global temperature development for the past 10, 20 or 50 years in the natural world without humans?

    Comment by Matti Virtanen — 7 Jul 2008 @ 5:04 PM

  120. You agree that ENSO has an effect on global temperature
    Have you checked what happens to the R^2 of CO2 vs global temperature if ENSO effects are allowed for?
    The R^2 should improve if CO2 is driving Temperature. Does it?

    Comment by Tom Bolger — 7 Jul 2008 @ 5:04 PM

  121. gavin: But of course data is used to build the models in general. How could it not be?

    I agree, but some here seem to think GCMs are constructed using _only_ known physics (such as quantum mechanics and thermodynamics), and are therefore not susceptible to any of the uncertainty of climatology data (such as UHI and bucket corrections).

    [Response: But that is correct. The issue of UHI does not come into the construction of the models. UHI or buckets or across-satellite calibrations affect estimates of the long term trends. Those trends are the test data for the models, not the input data. Read Schmidt et al, 2006 - not because it's my paper, but because it shows you what goes into tuning the models - there is no long term trend data used at all. - gavin]

    Comment by Steve Reynolds — 7 Jul 2008 @ 5:18 PM

  122. Matti #119:

    Well, that’s the models produced without CO2. There’s a lot else we do to change things and this isn’t easy to quantify: land clearance, overfishing, algal blooms (fertilisers being dumped), etc.

    It’s been done and that’s how they know that humans have done most of the damage. Because even by tweaking things to be most generous, about 1/3 of the heating change can be made to fit the “no human CO2″ scenario without putting something OBVIOUSLY wrong in there (like, say, trees outputting 100x the ozone we see in measurements today).

    That isn’t what you asked for, but the result is the same as far as climate is concerned.

    Comment by Mark — 7 Jul 2008 @ 5:32 PM

  123. Matti Virtanen (119) — I believe there is an IPCC AR4 FAQ page which does that. Check the links in the Science section of the sidebar.

    Comment by David B. Benson — 7 Jul 2008 @ 5:39 PM

  124. David B. Benson: You may care to read “Estimating Climate Sensitivity: Report of a Workshop (2003)”

    Thanks; interesting info, but as to be expected, not very conclusive.

    Comment by Steve Reynolds — 7 Jul 2008 @ 5:47 PM

  125. #110 Doug Bostrom,

    I spent 30 minutes looking for the succinct “illustrated” version. I just saw it in the last few days — but, that still means scores of potential links. I will try some more as I am now interested in saving those pages.

    #115 Martin Vermeer,

    Thanks for the fft tip :) For what its worth, I did see the same “fingerprint” frequencies in all the temperature data sets. However, they became less pronounced in the more heavily “reduced” data sets. Since they were “always there” and happened to be the same ones in the sunspot data, and the ones in the sunspot data were the same ones noted in the literature for sun phenomena as having physical basis, I assumed they probably were physical reality in the temperature data (doesn’t mean they were though).

    I don’t think the GISS staff is making things up for nefarious purposes. Heck, I’m a retired NASA guy myself — we didn’t make things up; but, we made mistakes often enough. I imagine the methodology was intended to meet a perceived need. However, as “noisy data” raised a flag with you — data with so many interpolated points and weighting adjustments (some of which seem unjustified at this stage of my ignorance) raises a flag with me.

    Anyhow, as you suggest, I’ll first work to understand the GISS process well enough to have an opinion on the method’s validity relative to its intended purpose (and other possible uses). If I remain concerned, there is a remote chance I’ll download the “raw” temperature data (millions of points I presume) and try my own reduction methodology — for the enjoyment and self edification.

    Comment by Allen — 7 Jul 2008 @ 6:50 PM

  126. Steve Reynolds, Any physical constant is determined from data–whether it is CO2 sensitivity or the gravitational constant. Science is empirical. You don’t get anything for free. However, once you’ve determined your constant, the degree to which your model reproduces behavior in the real world provides validation–and if the validation is strong, both the data used in fitting AND the validation result support your value for the constant.

    It’s pretty hard to find strong support for a low sensitivity.

    Comment by Ray Ladbury — 7 Jul 2008 @ 7:16 PM

  127. #110 Doug Bostrom,

    In answer to your query:

    Don’t know this site’s policy on linking articles. So, I’ll just say google “How much Estimation is too much Estimation” (Yahoo search works too). This gives an overview. Other articles at the site go into some depth regarding the details. Despite the title, the article is not too negative. It merely raises the questions I (or any interested party) might ask.

    [Response: "It merely raises questions" - hmm... the fact that not all data comes in on time and is not collected by NASA at all, isn't worth a mention I suppose? No, it's easier just to insinuate. - gavin]

    Comment by Allen — 7 Jul 2008 @ 8:20 PM

  128. Being a computer scientist and not a statistician I decided to hack out my own ENSO compensation back in May, here:

    http://reallyrealclimate.blogspot.com/2008/05/ten-year-hadcrut3-enso-effects.html

    The divergence between Gavin’s method and my own for the period beginning in 1998 is .029 C. So they are very close. I used HadCrut3 data not HadCrut3v.

    In any case, I plotted Gavin’s HadCrut3v data and his ENSO adjusted HadCrut3v data together, beginning in 1998, here:

    http://reallyrealclimate.blogspot.com/2008/07/gavin-schmidt-enso-adjustment-for.html

    The first thing that we can see is that there is very little divergence between the two. 0.0163 C for the 125 month period. The unadjusted HadCrut3v data fell by .00375 C over that interval and the adjusted data rose by 0.0125 C.

    So then comes the next question. If the decadal warming trend caused by CO2 is .2C, and if ENSO is now adjusted for, then where is the other .187 C of temperature rise? If we are going to attribute the flat trend to elements of natural variation, and if we have already accounted for ENSO, then to what elements of natural variation can we attribute the flat trend for the last decade?

    Comment by Tilo Reber — 7 Jul 2008 @ 9:56 PM

  129. In re 103:

    It doesn’t, they undoubtedly had an effect. But the sun is not driving the present global warming because there has been no clear trend in sunlight for 50 years.

    I guess I’m confused because I have looked at the correlation between the aa index and global temperatures and there does appear to be one. So other than say “Hogwash!” or something similar, how about pointing me at something which explains why there is no correlation.

    Comment by FurryCatHerder — 7 Jul 2008 @ 11:08 PM

  130. Allen (#127) wrote:

    … So, I’ll just say google “How much Estimation is too much Estimation” (Yahoo search works too). This gives an overview. Other articles at the site go into some depth regarding the details.

    Here is something I find particularly interesting:

    Global Temperature from GISS, NCDC, HadCRU
    January 24, 2008
    http://tamino.wordpress.com/2008/01/24/giss-ncdc-hadcru/

    Particularly the second chart. It shows that once you adjust for different base periods, Nasa GISS, Noaa NCDC and Hadley HadCRU are virtually identical. Some deviation in the very early part — due to the sparseness of data, I would presume, and some deviation around the end — given their different treatement of the Arctic — as Hadley basically omits everything beyond the land whereas Nasa interpolates. And it isn’t like this is the only methodological difference between GISS and HadCRU. (I don’t know as much about NCDC — so I will leave it out at this point.) But despite the differences in methodology, the results are nearly identical.

    This I submit constitutes evidence. But evidence for what?

    In my view, for the fact that both methodologies are reality-based — that while they are different, the methodologies each have a basis in reality for doing things they way they do, that they are both rational in how they deal with the fact that we have incomplete information. And as such, both work rather well in estimating average temperature anomalies, of adhering to a reality that exists independently of each — like cartesian and polar coordinate systems to a nearly flat plane.

    But I suspect that you would view their near-agreement as evidence for something else. And then the interesting question becomes whether there could ever be any evidence that would make you think otherwise — rather than interpret as further support for your view.

    PS

    You will find some rather interesting reviews of some the articles you are probably familiar with at the site above.

    Comment by Timothy Chase — 8 Jul 2008 @ 2:13 AM

  131. Ray, #126

    In a “debate” about the LHC on El Reg, one Anon Coward was insisting there was a real danger with it because, among other reasons, Plank’s constant was an estimate. Why was it an estimate? Because the statement of the constant had error bars.

    Good joined up thinking there.

    Maybe that AC was Steve?

    Comment by Mark — 8 Jul 2008 @ 3:48 AM

  132. Allen #125: go for it. I assume you are aware that the GIStemp software is freely downloadable. As is an alternative package called Freetemp by a guy called Van Vliet. Who was in a bit the same situation as you some years ago (when GIStemp wasn’t yet released) and decided to find out for himself. Which he very much did :-)

    Comment by Martin Vermeer — 8 Jul 2008 @ 4:29 AM

  133. Re 123: Thanks, I forgot those graphs. But they are too general for my purposes, and stop at 2000. I wonder why the IPCC in 2006 did not include five more years of temperature data. It will be interesting to see where they end in the 2014 report if the present (post 1998) trend continues.

    Comment by Matti Virtanen — 8 Jul 2008 @ 7:13 AM

  134. Tilo Reber posts:

    If the decadal warming trend caused by CO2 is .2C, and if ENSO is now adjusted for, then where is the other .187 C of temperature rise? If we are going to attribute the flat trend to elements of natural variation, and if we have already accounted for ENSO, then to what elements of natural variation can we attribute the flat trend for the last decade?

    This is, in fact, something he posts on every climate-related blog he can get to. He simply doesn’t understand the facts that A) the trend is not flat, and B) you can’t tell the trend from ten or eleven years of data, as I showed above.

    Half my post got deleted because I used a less-than sign where I should have used & lt ;. Could someone correct my post, please?

    Comment by Barton Paul Levenson — 8 Jul 2008 @ 7:50 AM

  135. 129 Timothy Chase,

    “…But I suspect that you would view their near-agreement as evidence for something else. And then the interesting question becomes whether there could ever be any evidence that would make you think otherwise — rather than interpret as further support for your view.”

    All I questioned was “… the validity of FFT analysis of the final GISS and HadCRUT3 temperature anomaly products …”

    It was all about my back of the envelope FFT analysis — nothing more.

    I’m new to this climatology and AGW. I have been paying absolutely no attention up until, maybe, three weeks ago when for some already forgotten reason I happened upon a “climate site” and became interested. Sure, I knew people were “concerned” about global warming — but, for me, it was not something I thought about. Considering how consuming it seems to many on the sites, that may be hard to fathom.

    One thing obvious from the start — this is an emotionally charged subject. People easily read ulterior motives into simple discourse and are really quick to write people off as being in one “camp” or another.

    Personally, at my current level of ignorance, here is what I believe: Global warming has obviously been happening over the last 100+ years. Atmospheric CO2 has been rising to “record levels” relative to the recent past. AGW is likely happening but is still based on “circumstantial evidence”. The AGW rate and the influence of “natural factors” have not been finally determined (my area of current interest). Much science remains to be done regarding consequences (good and bad). What should be done politically, is a different forum I presume.

    So, maybe that puts me in the “on the fence” camp :)

    Comment by Allen — 8 Jul 2008 @ 8:02 AM

  136. #132 Martin Vermeer

    I did not know about FreeTemp. Thanks.

    I presume, being so late in the game, anything I think of has already been done, and I do not want to reinvent any wheels I can download.

    Comment by Allen — 8 Jul 2008 @ 8:21 AM

  137. There is a lot of data about, Barton (104).

    If you look carefully you will see that the UAH monthly data from June 2001 to date shows a significant negative trend.
    Their mid-troposphere temperatures show very little trend from the start of the record (0.05 degrees per decade).

    There is a distinctly defensive tone to these posts, based on the suggestion that short term temperature changes cannot yield any significant information. Statistically, the time span of the record has nothing to do with significance. A trend is significant (at a given level of probability) if it accounts for a sufficient proportion of the variance in the data. It is not if it doesn’t.

    Returning to the blog (as stimulating as ever) I came across Barton’s paper on Saturation. I used the approach to add some calculations to Tamino’s explanation of the Lapse Rate at Open Mind. I would be very interested in Barton’s comments, particularly on the relative absorption of the atmosphere above Essenhigh’s extinction levels.

    Comment by Fred Staples — 8 Jul 2008 @ 9:12 AM

  138. #129 Furrycatherder

    Here’s a mantra for you. Correlation does not equal causation (neither does no correlation equal causation).

    Some things are coincidental and some complimentary in effect. Getting climate models to work right needs positive forces and negative forces of the existing elements that impose forcing. Solar variance is just one piece of the puzzle.

    http://www.agu.org/pubs/crossref/2005/2005GL023621.shtml

    The biggest problem people have in understanding this global warming event is narrowly scoped data and improper context of that data when weighed with the big picture of global climate.

    As I have stated before, with a properly narrowed scope, I can prove to you the world is flat.

    Some might disagree with me, but why should that matter. They might even have data that disproves my assertion, but why should that matter. I am only saying that I can prove the world in flat with my narrowly scoped view. If I am foolish enough not to look at other relevant data that would affect the outcome of my assertion, then that is what I am, a fool, though Fred Singer would simply smile and say, no, ‘the world is flat’; ‘smoking is not bad for your health’; CFC’s do not harm the ozone… you need to check the source and the history behind the source to get more perspective.

    If you are seeing a chart that proves otherwise, i.e. that this global warming event is caused by solar, it is likely either fraudulent or narrowly scoped, or both.

    Show us your data Furrycatherder.

    Also, reread, my post to you #59 above. Further warming is in the pipeline. Heck, we’re doing such a great job at warming the planet, we don’t even need sunspots to do it. Aren’t we industrious! Who needs that extra .3 W/m2 anyway…

    IPCC has us at 1.6 W/m2 but you have to remember they are in Switzerland, which is probably the most conservative country on the planet. So they are not going to speculate on anything. They need to run it through their filter of 2500 scientists to gain confidence. But a conservative number is not always the real number. Current forcing estimates done by our own governments leading scientists are showing 1.9 W/m2.

    Comment by John P. Reisman (The Centrist Party) — 8 Jul 2008 @ 9:52 AM

  139. Fred Staples says in 137:
    “Statistically, the time span of the record has nothing to do with significance.”

    Uh, the noise goes up with the square root of the number of samples taken. The signal goes up linearly.

    That is called Statistics.

    If you’d done O level maths you’d have learnt that.

    Comment by Mark — 8 Jul 2008 @ 10:13 AM

  140. Allen, I suggest the “Start Here” link at the top of the page, and the first link under “Science” in the right sidebar of the page, for your first few weeks’ reading.

    As you’ll note on climate blogs, there is a great deal of repetition, people will go from blog to blog posting the same beliefs and opinions, sometimes for years without changing anything they believe or opine.
    They aren’t “on the fence” — they haven’t even entered the ballpark.

    Reading at least the Spencer Weart’s history will avoid that sad fate.
    The science keeps changing. You can look it up.

    Comment by Hank Roberts — 8 Jul 2008 @ 10:21 AM

  141. #135 Allen

    I don’t think that puts you in the “on the fence” camp. It puts you in the ignorant camp by definition. Since you are fro NASA, I am confident that does not offend as debate is oft encouraged within the culture.

    http://www.merriam-webster.com/dictionary/ignorant

    Don’t worry though, no one knows everything and I have my own areas of ignorance where I am studying to learn system dynamic interactions and components. I strongly believe in lifelong learning.

    Since you’re form NASA, I’m curious where you live that you only recently noticed the global warming debate?

    Your statements indicate that you do not yet understand the major dynamics at play. I myself am not a scientist but I’ve been examining this for quite some time now and I love learning so it’s been fun.

    In your search for information you might want to question the sources and basis of the arguments you find in areas where there has already been proof of misleading or even scientific fraud.

    For example, your post #127 led me to Steve McIntrye’s web site. I beleive that is the same Steve that was involved in a congressional debate about the hockey stick his conclusions had substance but no significant relevance. In my opinion he wanted to muddle the argument and confuse people. I addressed his argument and many others in the following article,

    http://www.uscentrist.org/about/issues/environment/john_coleman

    which led to this conclusion submitted in testimony:

    http://www.pewclimate.org/node/2132

    The hockey stick became one of the most studied pieces of science and still held up. To this day, it still looks like a hockey stick, and it is still valid.

    So where you look for data and how narrowly scoped that data is and whether or not that data is relevant are critical factors.

    If you want to understand, you need to understand a lot.

    In post #127 you mentioned “It merely raises the questions I (or any interested party) might ask.” That is a common mistake, one I have made as well. Asking common questions is a big part of the problem for those that want to learn about this global warming event.

    A common question for example like how can Co2 be the main driver of climate if it lags behind warming in the natural cycle?

    The fact that Co2 is not the main driver of climate coming out of an ice age confounds people to this day… even though it is well established that Co2 is not the main driver of coming out of or going into ice ages, as that is regulated by the Milankovitch cycles.

    This global warming event is entirely different because we are actin contrary to the natural cycle and have departed from the expected trend of climate minus the GHG’s and other affects.

    My advice is study this site. There are literally thousands of sites out there now and most I have looked at are caught up in narrowly scoped views that are inconsiderate of the larger scope of the known, relevant, contextual, science.

    Context and relevance are key to understand. Without that, it’s barking up wrong trees and whack-a-mole in the carnival of human misunderstanding.

    Since you are a beginner as you have stated, keep this all in mind. There is an obvious concerted effort to confuse the issue. Context and relevance will bring you closer to the truth than naive assertions based on data out of context and less relevant. it’s a long road, but your in the right place.

    If you wish to discuss any of these matters, you can contact me through my web site. I’m still ignorant too, but I do my best.

    John

    Comment by John P. Reisman (The Centrist Party) — 8 Jul 2008 @ 10:37 AM

  142. Ray: Any physical constant is determined from data–whether it is CO2 sensitivity or the gravitational constant.

    Not distinguishing between constants known to many significant figures and parameters where even the sign is in dispute (cloud effects) is pretty unhelpful.

    Comment by Steve Reynolds — 8 Jul 2008 @ 10:55 AM

  143. Seve Reynolds in 142.

    If clouds are low down, it’s warming. If high up, it’s cooling.

    Now why is it that the uncertainty in cloud cover and cloud formation only makes things cooler?

    So, given it could go either way, why not ignore it for now? I mean, clouds don’t CARE what we want them to do, do they.

    Comment by Mark — 8 Jul 2008 @ 11:20 AM

  144. Speaking of ENSO, this year looks more and more like 1997, when ENSO raged at year end, but also when the Polar Vortex was really strong in the spring. Like this year when +200 knot stratospheric winds were measured in the Arctic. Looks like a strong El-Nino may be on its way:

    http://www.osdpd.noaa.gov/PSB/EPS/SST/climo&hot.html

    Comment by wayne davidson — 8 Jul 2008 @ 11:53 AM

  145. Steve Reynolds, The fact that the sign is not known for clouds may indicate a variety of things: 1)lack of data, 2)the net effect may be near zero, 3)the mechanism may be obscure or there may be competing mechanisms that make it difficult to determine how to include the effects in the model. I suspect that clouds fall under 2 and 3 above. Again, you have to look at things in the context of the model.

    Comment by Ray Ladbury — 8 Jul 2008 @ 11:56 AM

  146. Re: #129 The following site states why greenhouse gases have a much greater effect than the Sun and natural variability in explaining recent global warming.
    http://www.metoffice.gov.uk/corporate/pressoffice/myths/4.html

    Also the IPPC 2007 Summary For Policy Makers, The Physical Science Basis, in figure SPM.2 shows individual radiative forcing components. The Solar irradiance is given as contributing 0.12(0.06 to 0.30) watts/sq.meter, while the total net anthropogenic forcing is given as 1.6(0.6 to 0.30) W/M^2.
    http://www.ipcc.ch/ipccreports/ar4-wg1.htm

    Comment by Lawrence Brown — 8 Jul 2008 @ 12:38 PM

  147. gavin: Response[121]: Read Schmidt et al, 2006 – not because it’s my paper, but because it shows you what goes into tuning the models – there is no long term trend data used at all.

    Thanks; there is lots of good info there. I notice the range of climate sensitivity reported for your various models is 2.4C to 2.8C. Those values are lower than what some people would expect.

    Don’t the long term trends that are the test data for the models still influence model construction somewhat? If you see model predictions at odds with observed long term data, doesn’t that tend to influence selection of input parameters (that are poorly known anyway) to get better agreement?

    [Response: Not really, because ahead of time I don't know what the answer would be. - gavin]

    Comment by Steve Reynolds — 8 Jul 2008 @ 1:02 PM

  148. Excellent graphing. May I repost, with attribution, to The Red Mullet? http://theredmullet.blogspot.com

    Risa B

    Comment by Risa Bear — 8 Jul 2008 @ 1:06 PM

  149. Ray: I suspect that clouds fall under 2 and 3 above. Again, you have to look at things in the context of the model.

    My understanding (faulty as it may be) is 3. It generally takes a fairly high positive feedback from clouds to get a high climate sensitivity.

    Comment by Steve Reynolds — 8 Jul 2008 @ 1:08 PM

  150. Thanks to everyone who has offered advice and links. You’re becoming numerous enough that I do not want to spam with individual notes of appreciation.

    #141 John, to answer your questions:

    NASA Glenn RC, Ohio, USA, Materials Science, Microgravity Science, Project Scientist, Project Manager Spacelab and ISS experiments, retired 9 years. And/or under a rock? :)

    FWIW, on questions of science. I think it behooves the ignorant to remain on the fence :) Moreover, I think retaining objectivity probably requires I remain there as long as possible.

    No offense taken. Thanks for the links, I’ll visit them.

    Comment by Allen — 8 Jul 2008 @ 1:08 PM

  151. In re 138:

    #129 Furrycatherder

    Here’s a mantra for you. Correlation does not equal causation (neither does no correlation equal causation).

    You may wish to try that mantra on someone else. While correlation does not imply causation, there is only so much one can ascribe to chance, and proposing alternate explanations allows one to test those proposed explanations retrospectively. For example, exiting any of the minima whose entrance and exit corresponds to the aa index, but not to changes in CO2 concentration rules out their being caused by man-made CO2. Their short term rules out orbital forcing. The lack of CFCs rules out ozone depletion, etc. Occam’s Razor eventually demands that the most obvious cause — and the one that has the only significant correlation — is the correct cause. Namely, short term changes in temperature, such as seen during Dalton, Maunder, Spoerer, etc. minima are related to changes in total solar output.

    Some things are coincidental and some complimentary in effect. Getting climate models to work right needs positive forces and negative forces of the existing elements that impose forcing. Solar variance is just one piece of the puzzle.

    Right, and based on past observations (see Dalton, Maunder, Spoerer, etc. minima), the relationship of planetary orbits to periods of increased or decreased solar output, and the recent geometry of the various planets, and the solar barycenter, odds are pretty good that we’re due for a decade or more period of reduced solar output.

    The biggest problem people have in understanding this global warming event is narrowly scoped data and improper context of that data when weighed with the big picture of global climate.

    I’d argue that the biggest problem is “All or Nothing” thinking, a logical fallacy in which one argues that singular causes are responsible for all observations.

    Narrowly scoped, the present situation is either strictly caused by solar variations (in which case I believe the “solar variation” crowd will inappropriately gain credibility over the next 10 to 20 years as we work through the next below average solar cycle or two), or strictly caused by CO2 concentrations (in which case I believe the “CO2 concentrations” crowd will inappropriately lose credibility as the non-linear relationship (sensitivity is based on doublings, not linear increases) between increased CO2 concentrations, and forecasts for below average solar cycles reduces the longer term upward trend in global temperatures).

    More broadly scoped, a variety of factors are present, some of which are widely used by skeptics of global warming, and others which are used by proponents. The truth, suggests our dear friend Occam, is likely somewhere in between.

    Also, reread, my post to you #59 above. Further warming is in the pipeline. Heck, we’re doing such a great job at warming the planet, we don’t even need sunspots to do it. Aren’t we industrious! Who needs that extra .3 W/m2 anyway…

    Why? My re-reading it isn’t going to change your all-or-nothing approach and my belief that it is going to result in a diminished response to the problem. How about you actually read my posts for comprehension, rather than as something to knee-jerk rebut?

    Comment by FurryCatHerder — 8 Jul 2008 @ 1:12 PM

  152. Pardon me for being somewhat hypothetic (or pathetic as the case may be). I am still trying to figure out relationships.

    The SOI interacts with ENSO and deep ocean temperature is a strong driver. I don’t understand the lag times of influence yet, but am still reading.

    I am hypothesizing that the El Nino/La Nina oscillation is kinda like the Milankovitch cycles, where you have some big players (EOP) dancing through time.

    - Thermohaline Circulation
    - Schwabe Cycle
    - Seasonal SST Variation

    and that these

    are playing upon the SOI, NAO, PDO, AMO, ENSO

    Anyone want to play in my thought pool? Is anyone modeling this sort of relationship already? What other players may be strongly influencing here?

    Comment by John P. Reisman (The Centrist Party) — 8 Jul 2008 @ 1:39 PM

  153. On the topic of temperature series in general, can anyone point me to an archived copy of the 5.1 version of the UAH lower troposphere data? i.e. The version before the diurnal correction?

    Comment by cce — 8 Jul 2008 @ 1:47 PM

  154. Allen (#150)

    Problem is you’re not just sitting on the fence. You’re, um, “fertilizing the field”. And people trying to work in it keep stepping in it.

    Comment by Mark — 8 Jul 2008 @ 1:57 PM

  155. #127 Allen:

    Thanks. I suspected as much. That would be Steve McIntyre, still coasting on the momentum of “Hockey Stick Histrionics” as produced and directed by impresario Joe Barton, a costly production which in spite of heavy promotion and vast expense proved a flop with the critics. McIntyre’s more recent poetry (“Ode to Defamation of Jim Hansen”) can also be experienced as dramatic interpretations, performed in a workmanlike manner by such authors as the discredited “Steve Goddard”.

    Comment by Doug Bostrom — 8 Jul 2008 @ 1:57 PM

  156. #150 Allen

    My own ignorance aside, I am an objectivist in many ways. In fact, my uncle worked with Any Rand and wrote the book CAPITALISM (he likes it spelled in big letters). I am a huge fan of Ayn Rand, but I disagree with the way most people interpret her message in the ‘Fountainhead’ and ‘Atlas Shrugged’. She was talking about value in my read, not profit without attachment to value outside of an objective market. In fact I disagree with my uncle in many of his assumptions in his book as they are short sighted and mechanistic, whereas I am more confident that prescience rather that reactivity as a better rule for calculating economic policy considerate of sort/long term economic system health, but that is another discussion.

    I can only agree that being objective, to the extent possible is always important. But that is why I stressed relevance and context. This is a clean argument inside the science that is well known understood. And it is very dirty in the represented science that is out of context and less relevant, but held and proclaimed by some as science. That is confusing a lot of people unfortunately.

    Yes, there are many questions still, but not about what is already known. I assure you personally, you will discover this to be true as well. This part of the argument is pretty much done. GHG’s are the key to the models to explain this global warming event.

    The only possible argument against what is known is we don’t know what we don’t know. It sounds like a good argument until you realize that we know what the forcing components are in the atmospheric composition and we know how much forcing they provide, and we know the source of those components and how many ppm or ppt of those components exist as a result of human industrial process. That is quantifiable.

    I welcome all objective people to the debate :)

    Best,
    John

    Comment by John P. Reisman (The Centrist Party) — 8 Jul 2008 @ 1:58 PM

  157. #149:

    So you understand it to be option 3, too complex, yet you still know it will work in one particular way.

    Try skepticism on that idea for a change.

    Comment by Mark — 8 Jul 2008 @ 1:59 PM

  158. John P. Reisman (#156) wrote:

    My own ignorance aside, I am an objectivist in many ways. In fact, my uncle worked with Any Rand and wrote the book CAPITALISM (he likes it spelled in big letters). I am a huge fan of Ayn Rand, but I disagree with the way most people interpret her message in the ‘Fountainhead’ and ‘Atlas Shrugged’…

    John,

    Your uncle’s name is George, married to Edith. George, Alan Greenspan and Frederick A. Hayek had Ludwig von Mises as at a teacher at one point. Wow… I believe I offered to install a search engine for your uncle at one point. Can’t remember whether or not he accepted. A few people did — a certain dialectician you might know as well as a fellow who has been described as the Tom Brokaw of New Zealand.

    I should have guessed.

    As I see it, for the objective soul, no value or loyality can ever be placed before one’s adherence to reality, and objectivity demands that we recognize reality for what it is irrespective of ideology. It would appear that you see things the same way.

    Comment by Timothy Chase — 8 Jul 2008 @ 2:40 PM

  159. I will resist the temptation to discourse off-topically about Ayn Rand, except to note that her use of the term “objectivism” was ironic given that, as John Reisman notes, her philosophy emphasized values, and the capacity to value is the essence of subjectivity.

    As I understand the terms, “objective” refers to that which is accessible to multiple observers, while “subjective” refers to that which is accessible only to one observer. The scientific method, with its emphasis on replicable, quantifiable empirical observations, is powerfully suited to the investigation of objective phenomena, but has a more difficult time with the investigation of subjective phenomena. This does not mean that subjective phenomena are less “real” than objective phenomena, only that they are less readily accessible to traditional scientific methods of investigation.

    When discussing various observers’ attitudes towards some body of objective data, such as the data underlying the science of climate change, those who evaluate the data without undue ideological bias might better be described as “impartial” rather than as “objective”.

    Comment by SecularAnimist — 8 Jul 2008 @ 3:22 PM

  160. #158 Timothy Chase

    Yes.

    Comment by John P. Reisman (The Centrist Party) — 8 Jul 2008 @ 3:24 PM

  161. The first thing that we can see is that there is very little divergence between the two. 0.0163 C for the 125 month period. The unadjusted HadCrut3v data fell by .00375 C over that interval and the adjusted data rose by 0.0125 C.

    this is Tilo Reber at his best. when he started doing his “analysis” he still didn t understand how a trend line is calculated. (see the discussion on deltoid)
    now his useless stuff is repeated all over the denialist blogosphere. (see watts up)

    so, what is/went wrong?
    Tilo started by loking at a 10 year period. (yes, he was told that this is stupid) he tried to show, that the choice of start and end date (yes, he was told that he is cherry picking) does not influence the result.
    he came up with a pretty bizarre method: calculating different trends for the nino/nina phases during those years and summing them up. (yes he was told that this was dubious)
    he came to the conclusion, that ENSO does actually make the temperature trend over the last decade look POSITIVE. (yes, people told him that they had doubts) so he followed that the declining temperature (sic) was in spite of Enso events, not (partly) because of it.

    you don t believe me? well, it is online here:
    http://reallyrealclimate.blogspot.com/2008/05/ten-year-hadcrut3-enso-effects.html

    so now real scientists do a real analysis. they come to the OPPOSIT conclusion:

    when compensated for ENSO, temperature DOES increase.

    but instead of being all humble, Tilo seems to believe, that this result supports his ideas.

    he also is proud, that the difference between his “method” (the one showing that ENSO effect gave a positive trend over the last 10 years, 1998!) only shows a difference of 0.029°C over ten years to the real one. (in a century, that is just 0.3°….)

    (pretty tired, so stopping here…)

    Comment by sod — 8 Jul 2008 @ 4:28 PM

  162. “so now real scientists do a real analysis. they come to the OPPOSIT conclusion:”

    That’s a truely pitiful conclusion Sod. My result showed a very slight up trend contributed by the ENSO. The Thompson result showed a very slight down trend contributed by ENSO. Tiny differences around zero do not constitue an “opposite conclusion”.

    In Gavin’s words about the Thompson method:
    “There is no perfect way to do this – but there are a couple of reasonable approaches.”

    So implying that Thompson’s results are perfect and that mine are suspect when there is such a small difference between the two is truely absurd. By the way, you have yet to show any reason why my approach is not reasonable.

    But with all of the squabling aside, the conclusion that I reached remains true. We have a decadal flat trend and ENSO has not caused it. As you can clearly see, the Thompson ENSO corrected warming trend since 1998 is +0.0125 C. You can call that a positive trend if you like, but I call it flat. One century of such a trend would give you less than .125 C. That is flat.

    So wave your hands all you like Sod. My conclusions on Deltoid were correct. We have a missing .187 C of C02 forced warming for the decade and no way to account for it.

    By the way Sod, you are now more than half a million square kilometers behind in the Arctic sea ice race.

    Comment by Tilo Reber — 8 Jul 2008 @ 8:16 PM

  163. #151 Furrycatherder

    First, that mantra applies to all involved in science (along with many others), and for that matter all involved in reason; which is the purpose of this site (science and reason), if it does not appeal to you, maybe you are here for a different purpose?. I don’t actually like ascribing anything to chance, but between chaos theory, quantum theory, Newtonian physics and the shear number of causal relationships in the universe, I can’t explain everything in detail. So at a certain level of mathematic probability, we must deal with the numbers we have and look forward to the numbers we will get.

    At the same time, if you know what the numbers you have mean and that explains things pretty well, then that is what you work with. In other words, you go to war with the numbers you have, not the numbers you want.

    Please show me your valid, relevant, explanation in context with the forcing level that you are talking about. I don’t know your references so you might want to share them, unless they are a secret and you just want me to guess why you think solar is the cause of our current global warming event. Cycle 22 and 23 just don’t have enough energy to support the known forcing. In fact, none of the solar cycles since Galileo first started looking around 1611 had enough energy to increase forcing by 1.9 W/m2.

    As to Sir William of Ockham, you’ve been watching too many movies. Ockham’s Razor (from Ockham, England) is, Entia non sunt mulltiplicinda praetor nesectita tatum, by my recollection. And that means entities should not be multiplied more than necessary. The Jodie foster interpretation was, I would say, a loose interpretation, but not too uncommon. The idea of all things being equal the best solution is the most simple does not apply to your argument; simply because all things are not equal.

    It is fairly obvious you are trying to state that solar is the main driver of our current climate change. Am I wrong in this ‘comprehension’? My own interpretation of Ockham’s razor is don’t make a Rube Goldberg out of it if you don’t have too, or don’t split hairs when the issue is the whole head and the hairs are not the relevant problem. Einstein countered/complimented by saying make things as simple as possible, but not any simpler.

    I don’t think that Sir Ockham intended you to only examine a narrowly scoped data set in a wide array of complexity and try to build a conclusion on it, especially since other relevant information is known to be influential and changes the overall result and understanding. And while I may be wrong about my interpretation of your incorrect use of the Razor, I don’t think so. Nevertheless, you are trying to match something that simply does not match.

    I comprehend from your posts, that you are asserting that this global warming event can be attributed merely to solar forcing. If that is not your position, then why didn’t you say I don’t think solar is driving this global warming event? If that is your position, there just isn’t enough of ‘it’ (solar forcing) to support your point when weighed against the actual known forcing. (see my previous post #59… oh, that’s right, you don’t want to read that again).

    I would love to look at the data you are referring too that proves your point. Please direct me with some links.

    I’ve read your posts and rather than copying each statement of yours, I will address them generally. Your posts indicate a fundamental misunderstanding of the known understanding on the matter of the relevant science of this global warming event.

    I think the drunk driving analogy explains the natural variation on a different road pretty well. natural is not overriding human caused global warming, it is merely causing swerves on a different, path while we are warming. So yes, solar is influencing the climate in its natural cycle, but on a different trendline than the expected path without the GHG forcing. Again, you need to look at this in long term trends (id est, 30 years or more) and include ‘all’ relevant forcing components. Or are you only speaking about changes outside of the aggregate forcing?.

    Maybe you are not being clear enough in your posts. Your response indicates I ruffled your fur. Maybe I don’t understand your posts, maybe they are not that comprehensible, maybe you wrote words you did not intend to write. How precisely, do I not comprehend your posts? I think you are trying to say that this global warming event is caused by solar influence. Please correct me if that is wrong on my part.

    Proposing alternate explanations is one thing, proposing relevant alternate explanations is another. How precisely do you attribute the amount of forcing in the system of 1.9 W/m2 to a solar forcing of .3 W/m2. In what universe does .3 = 1.9 or 1.6?

    On what are you basing your solar assumptions on show me relevant work, peer review, peer response, show me reason, show me data that is contextually relevant to your assertion. I can offer an alternate explanation but that does not mean it will have any relevance at all. I’m kinda creative, I could make something up that sounded convincing to those that did not understand the components involved. But that would be arrogant of me, and in context of what this all means downright unethical.

    I’m not telling you anything that is not in the data that is currently understood so where am I wrong? I’m not afraid to say I’m the biggest idiot on the planet, knowing only the tinniest fraction of knowledge that exists and trying to understand complex things? But where am I wrong and where is the data that proves it.

    So when I come across a bunch of scientists doing empirical work that is comprehensive in nature and those scientists come to a consensus view about a particular subject, and the data supports the view, and the models support the view, and I’ve investigated it pretty thoroughly and came to similar conclusions of the basic science, I must admit I find that credible. Especially in the face of no reasonable contravening arguments that can hold water, such as ‘it’s solar’.

    I actually agree with your statement of “all-or-nothing” to a degree but again what is the relevant context, really? As I stated in the sentence to which you are responding with that statement, big picture is more important that all or nothing in this context, so why are you arguing that point?

    I’m not sure your consideration of non linear is in context either. The non linear nature of forcing is related more to positive feedbacks and changes that are still being studied, such as cyclic changes in moisture content and regional dispersion, the methane cycles in the ocean or the potential of methane clathrate/hydrate release , and of course the race to feed more people on a planet which will inevitably add more nitrous oxide to the atmosphere and create more dead zones in the oceans, droughts, floods, fires, dogs and cats living together, mass hysteria…. oops, different movie.

    You are maybe trying to be fair to the argument or you are fence sitting or you’re here for some other reason. Either way, you are missing the fundamentals of climate forcing and seemingly cherry picking your data to support your argument.

    I do not have an all or nothing approach, I examine the data and the models and the context and the relevance. It’s pretty simple stuff when you get to the aggregate fundamentals.

    You are obviously intelligent but intelligence does not equal understanding if pieces of the puzzle are either missing or ignored. You don’t want t re read my previous post, so I will say it again.

    Just for fun, let’s postulate what would happen to our warming trend if the sunspot activity died. Please for give my gross oversimplification.
    If we have no sunspot activity we lose .3 W/m2 of forcing.
    The current forcing is calculated around 1.9 W/m2
    1.9 – .3 = 1.6 W/m2
    Well, looks like we will still warm. As mentioned previously, there is a lot of extra forcing in the system and it will take time for the ocean to absorb the energy and give us a new equilibrium to forcing ration/balance.
    Why don’t we call the next extended solar minimum the ‘I wish it were cooler minimum’. That might be more appropriate.

    Unless I am wrong in my ‘comprehension’ of your posts. you are trying to say that solar is the main driver of this global warming event (please do correct me if I am wrong). The simple fact is that humans put some extra greenhouse gasses into the atmosphere and that is causing us to warm outside of the natural climate path. What am I missing here?

    I’ve read a bit on your blog and I’m very happy that you have installed an energy efficient AC unit. But that still does not mean that solar is the cause of this global warming event. Now, if I have this all wrong and that is not what you are saying, I apologize in advance. I try to understand things, but I have to admit that I’m not perfect either. hey maybe I’m just some moron and you should ignore me entirely?

    On the other hand, I should also compliment you that as far as I’ve seen, you have not pulled the hey, we don’t know what we don’t know argument. It may benefit your comprehension of this global warming event if you examine it from a perspective of forcing components and influences, rather than merely hey some data fits some other data.

    Okay, I changed my mind, I will place some of your statements in this post for context.

    “I know there is a strong tendency of most pro-global-warming posters here to ignore that giant ball of fire and its cyclical behavior, but on what planet does ignoring the Dalton and Maunder Minimums make sense? And when the Gore Minimum brings another short term cooling trend, how do you propose explaining that so people understand the difference between short term cooling, long term warming, and the need to do something?”

    - No one is ignoring the giant ball of fire and its behavior; no one is ignoring the Daulton and Maunder minimums. The Gore minimum statement is downright immature.

    “My particular form of denialism isn’t dangerous because it advocates a massive shift to renewable energy forms to avert an economic disaster which will also avert an environmental one. Based on that, I’m a relatively harmless crackpot.”

    - I’m not sure how to ‘comprehend’ what you are saying in what seems to be an obtuse convolution of I’m a denialist that thinks we need to save the environment from??? what the evil economics like the Keynesian model… or just a general break down because of peak oil? And don’t worry, I don’t believe you are “a relatively harmless crackpot”.

    fly in the face of what I understand to be well-established science. What are you going to say when the sun stays spot free for a while longer and the well-established relationship between a spot-free sun and lower global temperatures begins to contradict your remarks? When year after year, there are no new global high records, what do you say?

    - What are you going to say when the sun spots don’t return and the thermal system continues to absorb the existing forcing and raises global temperatures and we get new global high records? Lest we forget that 2007 tied as second warmest year in modern history while solar was in minimum phase and we were in la nina.

    If, as folks like myself argue, the puck-hitting-part is dominated by strong solar cycles 22 and 23, you still have to deal with the rise in global temperatures from before that. And if cycles 24 and possibly 25 are below normal, someone has to explain “natural variability” so that declines in either absolute temperature or rate of increase don’t serve to discredit the overall “increases in CO2 level cause increases in global temperature”.

    You are an absolute expert at misdirection in my opinion. I think if you work a little harder at it you can make it even more confusing for ‘folks’. You are indicating that 22 and 23 were ‘strong’ which caused the hockey stick part that hits the puck, but 18 and 19 were stronger while GMT was cooling, hmmm….

    I guess I’m confused because I have looked at the correlation between the aa index and global temperatures and there does appear to be one. So other than say “Hogwash!” or something similar, how about pointing me at something which explains why there is no correlation.

    - First, the aa index you are referring to http://www.realclimate.org/index.php?p=42 breaks any obvious correlation in 1990. You seem to be falling into the same trap that the great global warming swindle movie fell into. . this is a good time to mention again that correlation is not causation, especially when the correlation breaks but the other rules still apply. you really need to understand forcing levels to get this in context. How about you go reread my post #59… oh dang it, I forgot you don’t reread.

    Why? My re-reading it isn’t going to change your all-or-nothing approach and my belief that it is going to result in a diminished response to the problem. How about you actually read my posts for comprehension, rather than as something to knee-jerk rebut?

    - What on earth does your rereading my post have to do with me changing anything. First I don’t have an “all or nothing approach”. The statement itself is extremely odd. I actually believe there are positive and negative forces, but based on the data models and observations the positives are outweighing the negatives. If something changed and suddenly a bunch of negative forces came into play, enough to knock down the forcing say 2 W/m2, then my perspective would change based on the data to the new information. The problem is that negative forcing does not exist at this time, so there is no reason to believe we are going to start cooling in the foreseeable future.

    - If you are actually only talking about diminished responses to the problem??? then try to present a less confusing argument and specify with clarity and precision what you are trying to say. If you really want to use Ockham’s Razor properly, this is where you should apply it. But your arguments all over the place! From what you have written in this thread, it is very difficult to discern with precision where you stand on your understanding. if you really are on the fence or a denialist that isn’t dangerous, whatever that means… I cant tell what you are trying to say. maybe try not multiplying your entities beyond what is necessary to present your argument and then ‘folks’ like me can comprehend you better.

    And why not use your real name, real people do? What it seems you are trying to do is confuse things. I absolutely may be wrong about that, but that seems the net effect even if it is not intentional. if it’s not intentional then reconstruct your argument so it makes sense to ‘folks’. Your fence riding gymnastics are only good, in my opinion, for distracting ‘folks’ from the real issue, that of the science, the models, and the observations. You distract from the context, and you distract from the relevance of one data set over another, you distract from the relevant argument, your distracting…

    What you clearly don’t seem to understand, in my opinion, is that 2007 was a solar cycle minimum year and a la nina year, and it still tied for 2nd warmest year in modern history. You simple don’t understand GHG forcing in its current context and relevance?

    Good night and good luck,
    John

    Comment by John P. Reisman (The Centrist Party) — 8 Jul 2008 @ 9:03 PM

  164. Fred Staples posts:

    If you look carefully you will see that the UAH monthly data from June 2001 to date shows a significant negative trend.

    It shows a significant negative trend, Fred, because you’ve artificially inflated the number of points by using monthly rather than yearly data. The characteristic time scale for climate or climate change is 30 years. What you did is equivalent to me saying the temperature has gone up significantly from 5:40 AM to 7:40 AM, dividing it into 121 minutely temperature readings, and using the “significant” results to prove that the oceans will boil tomorrow.

    Comment by Barton Paul Levenson — 9 Jul 2008 @ 6:41 AM

  165. Re: #134

    BPL says

    This is, in fact, something he posts on every climate-related blog he can get to. He simply doesn’t understand the facts that A) the trend is not flat, and B) you can’t tell the trend from ten or eleven years of data, as I showed above.

    But the trends from 1988 to around 1994 that you calculated were all significantly affected by the Pinatubo eruption in 1991. Check out the graphs in Gavin’s post – particularly the second one (ENSO corrected). The huge dip due to Pinatubo is obvious.

    For what it’s worth I don’t think a 30-year trend is adequate. It should be at least 70 years to account for PDO cycles etc. I know there are issues with data accuracy the further back you go, but these are being resolved (e.g. 1940s SSTs). Anyway, here’s something to think about. It’s not very scientific and it does cherry pick (sort of), but I like it because it agrees with my own ‘estimate’ of sensitivity to CO2.

    I was looking at Gavin’s data and trying to find a year when conditions were the same (or as near as possible) as the past 12 months (June 2007 to May 2008), i.e. La Nina, solar minimum, seasonal etc. The best I could find was June 1943 to May 1944. According to the ENSO-corrected data, the ENSO effect, averaged over the 12 month period, for 1943/44 was ~ -0.06 deg C. For 2007/2008 it was ~ -0.05 deg C. We had a solar minimum in 1944. We have (or should have) a solar minimum in 2008. The PDO shifted to a negative phase in 1943/44. There are indications that the PDO may have gone negative recently.
    Average temperature anomaly for June 1943 to May 1944 is 0.18 (0.24 ENSO-corrected). Average temperature anomaly for June 2007 to May 2008 is 0.44 (0.49 ENSO-corrected)

    A difference of around 0.26 deg C (0.25 ENSO-corrected) – call it 0.3.With a change of forcing of around 1 w/m2 since 1944 that gives us a sensitivity of 0.3 K/w/m2 or slightly more than a 1 degree increase for CO2 doubling.

    Comment by John Finn — 9 Jul 2008 @ 6:46 AM

  166. “…The characteristic time scale for climate or climate change is 30 years….”

    (Barton Paul Levenson)

    Says who? Is the definition based on the PDO cycle length or what? We’ve gotten into the absurd world of semantics, not science, when we say if it’s a short term trend, I guess 10 years or less, it can’t be climate change. Or maybe the definition is “..if we don’t understand the reason for the variability, it is just noise, not climate change…”

    How about this: if I could point to a state change in the radiative balance of the earth that started 6 years ago, would you say unless that state change lasts 24 more years it’s not climate change?

    Regards, BRK

    Comment by Brian Klappstein — 9 Jul 2008 @ 7:51 AM

  167. Brian, Actually, the definition is not arbitrary at all. We are looking to differentiate a positive, monotonic trend from background noise oscillating around it. Thirty years is merely where the trends due to the signal emerge with high confidence from the noise. So, yes, six years would be weather–solar or otherwise–unless we have good physical reasons to presume that it will persist on climatic timescales.

    Given that you don’t understand this, ever wonder what else you don’t understand about climate science?

    John Finn, Other than the fact that you are cherry-picking two years and that we don’t have a comparison of the relative strengths of the La Ninas, etc., I’d merely amend your derivation to say
    Sensitivity>1 degree per doubling, as there are long-term feedbacks the measurement does not include.

    Comment by Ray Ladbury — 9 Jul 2008 @ 8:26 AM

  168. That’s a truely pitiful conclusion Sod. My result showed a very slight up trend contributed by the ENSO. The Thompson result showed a very slight down trend contributed by ENSO. Tiny differences around zero do not constitute an “opposite conclusion”.

    that one is funny. so the person who challenged the scientific consensus, that ENSO had a DOWNWARD effect on the trend over the last decade now believes, that whether it is up or down doesn t really matter.

    In Gavin’s words about the Thompson method:
    “There is no perfect way to do this – but there are a couple of reasonable approaches.”

    what gavin said is very sensible. but there are obvious IMPERFECT ways of doing it. like yours.

    and even choosing an imperfect way is not bad in itself.
    but choosing an imperfect way, getting a false result and spreading it all over the internet IS bad.

    So implying that Thompson’s results are perfect and that mine are suspect when there is such a small difference between the two is truely absurd. By the way, you have yet to show any reason why my approach is not reasonable.

    i told you that i have doubts about adding the results together. you were told a better (standard!) way of doing it as well. you chose to ignore all of it and spread your nonsense.

    But with all of the squabling aside, the conclusion that I reached remains true. We have a decadal flat trend and ENSO has not caused it. As you can clearly see, the Thompson ENSO corrected warming trend since 1998 is +0.0125 C. You can call that a positive trend if you like, but I call it flat. One century of such a trend would give you less than .125 C. That is flat.

    sorry Tilo, but i am slightly sceptical of a person, who denies to look at the STATISTICAL SIGNIFICANCE of his trend lines.

    i guess i don t care, what you define as flat. i am sorry.

    So wave your hands all you like Sod. My conclusions on Deltoid were correct. We have a missing .187 C of C02 forced warming for the decade and no way to account for it.

    that would be right, if we were discussing the claim, that EVERY decade has to show a warming of exactly 0.2°C (or more). unfortunately, we don t discuss such a stupid claim.
    if you had listen to what people told you about the weather noise in short term climate observations or about SIGNIFICANT timescales in this discussion, you wouldn’t be wrong on yet another point. alas, you are.

    By the way Sod, you are now more than half a million square kilometers behind in the Arctic sea ice race.

    far of topic. my position can be found on the web. in short, i don t support a comparison with an outlier. the denialist iceage claim didn’t manifest in arctic sea ice. calling any ice extend above the long term absolute low of 2007 a sign of a reversed trend, is absurd.

    [Response: please can we keep the squabbling to a minimum? - gavin]

    Comment by sod — 9 Jul 2008 @ 8:34 AM

  169. Temperature noise is not white noise.
    Temperature noise is not white noise.
    Temperature noise is not white noise.
    Temperature noise is not white noise.
    Temperature noise is not white noise.

    Comment by tamino — 9 Jul 2008 @ 9:21 AM

  170. In re 162:

    1). Thanks for demonstrating all-or-nothing thinking again.
    2). Enough people here know who I am in real life already. My real name is really none of your business.

    Here’s the argument –

    1). I reject IPCC BAU projections, not because we can’t destroy the environment if we keep burning fossil fuels, but because we’ll destroy the economy long before hand. Have you checked the news lately about recessions, bear markets, food shortages, unemployment, etc? I’d argue the evidence is strongly on my side. I’ve maintained this same position long before oil reached half its current price, so it isn’t a fad or some frantic effort at fence sitting.

    2). I reject all-or-nothing thinking, not because there isn’t an upward trend in temperature caused by rising CO2 levels, but because people understand “weather” more intuitively than “climate”. When the greatly-above-average hurricane seasons of 2006 and 2007 failed to materialize, that fed into the skepticism of people I’ve spoken to regarding AGW. I explained to pro-global-warming people why ’05 was a fluke and was attacked then as a “denialist”. Again, evidence is now firmly on my side as both ’06 and ’07 were less intense than ’05 and now ’08 is looking to be less intense than ’05 as well. That’s the difference between “weather” and “climate”. Using “weather” (hurricane season forecasts, for example) to demonstrate “climate change” can backfire, and I believe it has in this specific instance.

    3). Buzz words aren’t going to convince me that you have a clue what “Correlation Does Not Imply Causation” means. There have been too many “coincidental” climate minima associated with too many solar minima. Not understanding the precise causal relationship between solar minima and climate minima is not the same as there not being a causal relationship. We do know, for example, that strong solar flares dramatically heat and expand the upper atmosphere, and we also know that periods of higher solar output have the same effect. Likewise, we know that periods of reduced solar output don’t have that same effect, so there is definitely a relationship between solar activity — “space weather” — and the upper atmosphere. That the last two climate minima (Dalton and Maunder) were also associated with solar minima is well known, as is the fact that the aa index has increased significantly during the 20th century, and “coincidentally” with changes in the long-term upward trend. Doesn’t mean CO2-related climate change isn’t happening, only that “weather” is the sum of more than one input.

    What does this mean in terms of an overall argument?

    It means I believe we’re due to enter a period of either reduced warming, or moderate cooling, which will be followed by a stronger period of warming as the sun exits the forecast period of low activity for SC24 and possibly SC25 and the effects of increased CO2 levels and increased solar output are combined.

    I also believe that more emphasis should be placed on economic arguments for moving away from non-renewable carbon-based fuels because those impacts are more obvious at present than longer-term environmental impacts. I don’t reject the belief that increased CO2 levels result in global warming, only that the long-term environmental arguments are weaker than the short-term economic ones. Or in other words, my present gasoline bill is about $4,800 per year (yeah, $400 a month), and I can do a gasoline-to-electric conversion for about $10,000 or less than 3 year payback on the entire vehicle.

    As for walking the walk, to the best of my ability to control my own life, I’m carbon negative. I become more carbon negative each day (on average ;) ), and actions this month alone should reduce my CO2 output 3/4 of a ton per year. I’m about 3 or 4 tons a year negative because I was neutral once upon a time. My personal financial investment in renewable energy is north of $30K, and will increase as I invest in renewable technologies to move further away from obscenely expensive motor fuels. In my professional life, I’m actively involved in researching solutions in the areas of renewable energy and power management technologies and currently have approximately 25 patents and/or applications in process. And no, I’m not going to tell you their application numbers either — my name really is none of your business.

    If you think I’m a “denialist”, I think you’re a putz.

    Comment by FurryCatHerder — 9 Jul 2008 @ 11:17 AM

  171. http://junkscience.com/MSU_Temps/Warming_Look.html

    Now we have temperature data up to June 2008, and it looks like 2008 will be as cool as 2000 was. Looking at the Hadley numbers, there has been no global warming since 2000:

    http://junkscience.com/MSU_Temps/HadCRUG.html

    The next couple of years will be very interesting. If global warming does not pick up, then IPCC climate models come under serious doubt.

    If IPCC models turn out to be wrong, that is no big surprise. I looked at the knowledge behind IPCC models. The margin of error in various ‘forcings’ and feedback loop strengths is so big that there is a reasonable probability that global climate will cool in the next decade.

    Comment by Heikki T — 9 Jul 2008 @ 11:20 AM

  172. “…So, yes, six years would be weather–solar or otherwise–unless we have good physical reasons to presume that it will persist on climatic timescales….”

    (Ray Ladbury)

    The 30 years of trend is only required because the signal is weak relative to the noise. A stronger signal would take less time to discern. I think a better definition of climate change would be a recognizable radiative balance state change that appears immune to short term cycles like ENSO and seasonal cycles. Meaning it doesn’t have to be 30 years long, maybe not even 10 years long.

    As for your “if it’s 6 years it must be solar or weather not climate change” statement, isn’t that a kind of circular logic? As in: since we know solar changes can’t force climate, if we see a solar signal in the data, we can reject it as climate change.

    Regards, BRK

    Comment by Brian Klappstein — 9 Jul 2008 @ 11:25 AM

  173. In re #167:

    John Finn, Other than the fact that you are cherry-picking two years and that we don’t have a comparison of the relative strengths of the La Ninas, etc., I’d merely amend your derivation to say Sensitivity>1 degree per doubling, as there are long-term feedbacks the measurement does not include.

    If I read the referenced post correctly, there’s also the issue that one has to include a sufficient period of time to get sufficient CO2 concentration change log base 2.

    This is the point I was trying to make in an earlier post — climate change per increase in PPM CO2 is declining, and will continue to decline (deltaT per PPM is logarithmic, so first derivative is positive and second is negative).

    Comment by FurryCatHerder — 9 Jul 2008 @ 11:26 AM

  174. Re: BRK @ 166: “Says who? Is the definition based on the PDO cycle length or what?”

    I believe 30 years is the agreed definition for climate used by the World Meteorological Organization. It is also used by both GISS and Hadley Met Centre for calculating temperature anomalies against 30 year base periods.

    Comment by Jim Eager — 9 Jul 2008 @ 11:50 AM

  175. Sod: #168
    “that would be right, if we were discussing the claim, that EVERY decade has to show a warming of exactly 0.2°C (or more).”

    There is the point that you are missing. If greehouse theory is correct, and if we are getting the expected levels of CO2 increase (which we are), then without any elements of natural variation to change the trend, every decade should show close to .2C increase. Or even if we allow for an error range and say that it is .1C to .3C, then every decade must show that increase within that range unless there are elements of natural variation that take us outside of that range.

    And what have we had in the past ten years to give us a flat trend. ENSO? No. Volcanism? No. Solar? Yes, but it is claimed to be far too small to override CO2 forcing.

    So here is the issue. We are clearly outside of that range. The elements of natural variation that have taken us outside that range are unknown. Therefore it is quite possible that we do not know enough about natural variation to compute climate sensitivity.

    The only other option that you have is to say that 10 year variation is noise that happens without a cause. And I do not believe that.

    [Response: This is nonsense. The idea that ENSO is the only kind of intrinsic variability is silly. Look out of your window - and see planetary waves (of various wavenumber), the Madden-Julien oscillations, the NAO, the PDO, the PNA, the SAM, COWL, baroclinic instability, African waves, Antarctic dipoles etc etc. There is no shortage of variability in short term records. What would meteorologists have to talk about otherwise? - gavin]

    Comment by Tilo Reber — 9 Jul 2008 @ 12:16 PM

  176. John Finn states:
    “But the trends from 1988 to around 1994 that you calculated were all significantly affected by the Pinatubo eruption in 1991. ”

    Wee problem. The Pinatubo eruption, powerful though it was, did not release significan tachyon energy. Therefore events before its eruption (say, 1988, 1989 and 1990) can not have been affected by the explosion.

    If the problem is the method by reaching the 1988-91 figures then please elucidate. BPL can’t help you understand without this info.

    PS: tamino, #169, there is no context so I’m assuming this is regarding the “noise goes up less quickly than the signal”.

    And my response is “So?”

    If the base variability is independant of your correlation testing then there’s no (or little) difference between noise and uncorreleated variability.

    E.g. Adult heights vary significantly but also vary closely related to diet.

    So to find out how much diet affects adult heights, you can’t take one person from each dietary group and correlate because inherent variability swamps the individual effect of diet. But if you take 100 from each dietary group, the genetic and other variables are not correlated to diet and so are effectively random within the dietary group. And so the signal is 100 times stronger wrt dietary effects and the internal variability is 10 times stronger because we have 100 more people and therefore some variability within that group.

    And so the signal can be teased out eventually.

    The strength of the signal compared to the noise tells you how much you need to collect together to reduce the variability within the selection group. The smaller the signal or the bigger the noise, the more selections need to be collected within the group.

    And for climatology temperatures, 30 is the minimum that can give any suitable signal for the noise. Adding more years helps increase the signal but you will be hiding information, so you select a period that is the minimum feasible and work with that. If you can add more data without losing information, you can do that with the 30 year means.

    Comment by Mark — 9 Jul 2008 @ 12:51 PM

  177. Wee problem. The Pinatubo eruption, powerful though it was, did not release significan tachyon energy. Therefore events before its eruption (say, 1988, 1989 and 1990) can not have been affected by the explosion.
    If the problem is the method by reaching the 1988-91 figures then please elucidate. BPL can’t help you understand without this info.

    The Pinatubo eruption would have affected the least squares linear trend for any of the previous 3 years (and before that). BPL, I’m quite sure, understands this.

    Comment by John Finn — 9 Jul 2008 @ 1:19 PM

  178. re: 171. “Looking at the Hadley numbers, there has been no global warming since 2000…”

    Gee, a denialist cherry-picking years…again! What a surprise. Not. Cherry-picking data still does not change the hard facts re: AGW trends. Ironically, in this same thread there is a specific discussion regarding the standard 30-year period for climate trend analysis. How conveniently ignored.

    Comment by Dan — 9 Jul 2008 @ 2:07 PM

  179. What a strange comment, Barton (164). It is certainly true that the calculated significance will improve with the number of data observations, but we would expect the precision to improve if we have more measurements.

    In the calculation for F the numerator (the explained variance) depends on the number of observations, while the denominator (the residual variance), does not.

    Whether or not 30 years (167) is sufficient to separate the noise (the residual variance) from the signal (the trend) depends entirely on the size of the trend and the random scatter in the data.

    The UAH data is presented monthly. If we choose to calculate a regression based on longer periods all we will do is lose information.

    Take the 10 years of UAH data from January 1998 to December 2007 – 120 months, 10 years, or 1 decade.
    If we chose to calculate per decade (one data point) we would lose all the information about the trend.
    If we calculate per year we have 10 points, a slope of 0.0057 degrees per year, and a probability of 73% that the slope has arisen by chance.
    If we retrieve the lost monthly information we have 120 points, the slope is 0.0052 degrees per year and the probability of that slope arising by chance falls to 34% (still not significant) because we have more quite legitimate data points.

    To be frank, Barton, you may want to reconsider your comment about the minute temperatures. If you measure the temperature at 5.40 am and 7.40 all you have is 2 data points – not enough to calculate a regression trend.

    Actually, we are not entitled to extrapolate any of these calculated trends unless we have a separately verified physical explanation for the trend to which the data (all of it) conforms. When you look at the UAH mid-troposphere data do you really think, Barton, that we have any such verification?

    Tamino (169) is presumably telling us that temperature data is not random because each value is related (to some extent) to the preceding values. His analysis of the Central England Temperatures is worth a visit. He uses the monthly records.

    Comment by Fred Staples — 9 Jul 2008 @ 3:34 PM

  180. “…I believe 30 years is the agreed definition for climate used by the World Meteorological Organization…”

    (Jim Eager)

    I know, I was being somewhat sarcastic. The logic of the 30 year trend is pretty impregnable. “We’ve defined climate change as a trend you can only discern after 30 years. Now sit down and shut up.” Or maybe: “if you think you detect a climate regime change in 2002, call us in 2032 and we’ll check to see if you’re right”

    Regards, BRK

    Comment by Brian Klappstein — 9 Jul 2008 @ 4:00 PM

  181. #170

    1). Thanks for demonstrating all-or-nothing thinking again.

    — Your logic seems quite backward. I’m not-all-or-nothing, I’m show me your data to support your assumptions, and I will believe it when I see it as long as it is in context and has relevance.

    2). Enough people here know who I am in real life already. My real name is really none of your business.

    — Maybe your right? Maybe not. When I here people make claims that are misleading in this argument (AGW) based on assumptions that are either not substantiated, or not substantiable, and knowing that millions if not billions of lives may be at stake. I kinda think those people should not hide behind monikers like furrycatherder and take full responsibility for their unsubstantiated claims and their ramifications. But it is your choice to hide behind your moniker.

    Here’s the argument –

    1). I reject IPCC BAU projections, not because we can’t destroy the environment if we keep burning fossil fuels, but because we’ll destroy the economy long before hand. Have you checked the news lately about recessions, bear markets, food shortages, unemployment, etc? I’d argue the evidence is strongly on my side. I’ve maintained this same position long before oil reached half its current price, so it isn’t a fad or some frantic effort at fence sitting.

    — Show me your data to support your assumptions. Otherwise you are only giving your opinion based on your assumption. You seem be ignoring the fact that we have a lot of coal yet to burn, and coal sands. It does not matter that you have maintained your same position long before oil reached half its current price. You are arguing based on your opinion that the evidence is strongly on your side but you still have not answered a single question of mine to show your data to support your claims, nor have you posted any links to support your claims. You have however made claims that are simply not true such as the correlation of the aa index to global temperature; and you claim this as evidence to support your assumptions; and you still apparently don’t understand forcing.

    2). I reject all-or-nothing thinking, not because there isn’t an upward trend in temperature caused by rising CO2 levels, but because people understand “weather” more intuitively than “climate”. When the greatly-above-average hurricane seasons of 2006 and 2007 failed to materialize, that fed into the skepticism of people I’ve spoken to regarding AGW. I explained to pro-global-warming people why ‘05 was a fluke and was attacked then as a “denialist”. Again, evidence is now firmly on my side as both ‘06 and ‘07 were less intense than ‘05 and now ‘08 is looking to be less intense than ‘05 as well. That’s the difference between “weather” and “climate”. Using “weather” (hurricane season forecasts, for example) to demonstrate “climate change” can backfire, and I believe it has in this specific instance.

    — I’m glad you reject all-or-nothing thinking, so stop thinking that way, or at least stop writing that way. You are confusing people. The above average ‘global’ TC season did materialize, it just didn’t all make the news due to the lack of landfall and proximity. It’s not weather events that you examine in climate, it’s the trend of weather events. You need to explain that to your friends. That is precisely why short term does not override long term trend analysis. maybe it confuses people because you did not explain that to them in an understandable manner? You can’t compare a trend ’06 / ’07 to ’05, and call it climate. Yes people intuitively relate to weather rather than climate but you can explain it to them and as long as you don’t confuse them too much, they will understand. You can use weather to explain climate as long as you explain the relevance and the context. Maybe your not giving good context as is indicated by your posts here in this thread.

    3). Buzz words aren’t going to convince me that you have a clue what “Correlation Does Not Imply Causation” means. There have been too many “coincidental” climate minima associated with too many solar minima. Not understanding the precise causal relationship between solar minima and climate minima is not the same as there not being a causal relationship. We do know, for example, that strong solar flares dramatically heat and expand the upper atmosphere, and we also know that periods of higher solar output have the same effect. Likewise, we know that periods of reduced solar output don’t have that same effect, so there is definitely a relationship between solar activity — “space weather” — and the upper atmosphere. That the last two climate minima (Dalton and Maunder) were also associated with solar minima is well known, as is the fact that the aa index has increased significantly during the 20th century, and “coincidentally” with changes in the long-term upward trend. Doesn’t mean CO2-related climate change isn’t happening, only that “weather” is the sum of more than one input.

    — I’m ONLY using your examples to make my point. You say it is solar yet you reference the aa index as a correlation equals causation example, yet you are wrong, yet you still claim you are right. You are confusing people. Study the forcing levels first, then come back. All the correlation between solar and temperature have validity to the extent of their forcing influence. We are not discussing weather here. we are discussing climate. Show us your data furrycatherder, why should we all have to go chasing your data. Just post the links so we can look at them and see how relevant they are. You keep going back to Daulton and Maunder, but what is your context? There are causal relationships between solar forcing and climate, but what is the degree of relevance? .3 is less than 1.6 and 1.9

    What does this mean in terms of an overall argument?

    It means I believe we’re due to enter a period of either reduced warming, or moderate cooling, which will be followed by a stronger period of warming as the sun exits the forecast period of low activity for SC24 and possibly SC25 and the effects of increased CO2 levels and increased solar output are combined.

    — What is it you still don’t understand about .3 is not equal to 1.6 and 1.9? Substantiate your claims, I’m begging you. Whose forecast? On what basis? Where is the data? Is it peer reviewed? Has it gone through peer response? Did it survive peer response? The ocean will keep absorbing the forcing energy and warming, we don’t need sunspots anymore to warm. The next solar cycle whenever it happens will only add more forcing to the current forcing and give us a bump.

    I also believe that more emphasis should be placed on economic arguments for moving away from non-renewable carbon-based fuels because those impacts are more obvious at present than longer-term environmental impacts. I don’t reject the belief that increased CO2 levels result in global warming, only that the long-term environmental arguments are weaker than the short-term economic ones. Or in other words, my present gasoline bill is about $4,800 per year (yeah, $400 a month), and I can do a gasoline-to-electric conversion for about $10,000 or less than 3 year payback on the entire vehicle.

    — This web site is about the science, not the ecnomics. The economic argument is not a climate science issue, it is a resulting issue, a policy issue, combined with a slew of other issues such as peak oil and industry gone wild that long term has negative return on investment written all over it, due to short term thinking inconsiderate of the ramifications of egregious exploitation of the earths resources for the benefit of a few at the cost of many. The science should certainly drive policy but that is a separate issue. I think it should be discussed too. I don’t ind it being mentioned here, but this web site is about the science not the economy.

    As for walking the walk, to the best of my ability to control my own life, I’m carbon negative. I become more carbon negative each day (on average ;) ), and actions this month alone should reduce my CO2 output 3/4 of a ton per year. I’m about 3 or 4 tons a year negative because I was neutral once upon a time. My personal financial investment in renewable energy is north of $30K, and will increase as I invest in renewable technologies to move further away from obscenely expensive motor fuels. In my professional life, I’m actively involved in researching solutions in the areas of renewable energy and power management technologies and currently have approximately 25 patents and/or applications in process. And no, I’m not going to tell you their application numbers either — my name really is none of your business.

    — I’m very happy you are carbon negative. I’m also not surprised that you have approximately 25 patents and/or applications in process.

    If you think I’m a “denialist”, I think you’re a putz.

    — I don’t know you so I can only go by your own words, “My particular form of denialism isn’t dangerous because it advocates a massive shift to renewable energy forms to avert an economic disaster which will also avert an environmental one. Based on that, I’m a relatively harmless crackpot.” How is it precisely you want me to interpret your own claim that you subscribe to a “particular form of denialism”.

    — Now with this new post of yours you still have not substantiated any of your claims, not one. Please, please, pretty please, with sugar on top, substantiate your claims; otherwise please stop spouting opinion, it confuses people.

    — With kindest regards,
    — John

    Comment by John P. Reisman (The Centrist Party) — 9 Jul 2008 @ 4:19 PM

  182. FurryCatHerder (170), interesting thoughtful post.

    Comment by Rod B — 9 Jul 2008 @ 4:49 PM

  183. ‘John P. Reisman (The Centrist Party)’ #181:

    2). I reject all-or-nothing thinking, not because there isn’t an upward trend in temperature caused by rising CO2 levels, but because people understand “weather” more intuitively than “climate”. When the greatly-above-average hurricane seasons of 2006 and 2007 failed to materialize, that fed into the skepticism of people I’ve spoken to regarding AGW. I explained to pro-global-warming people why ‘05 was a fluke and was attacked then as a “denialist”. Again, evidence is now firmly on my side as both ‘06 and ‘07 were less intense than ‘05 and now ‘08 is looking to be less intense than ‘05 as well.

    What a convenient way to avoid admitting that despite the 2006-7 Atlantic hurricane seasons being less active than 2005 , there is nonetheless a strong upward trend in Atlantic hurricane activity – which, while perhaps not caused by global warming, shows a correlation with rising sea surface temperatures in the Atlantic, and with changing aerosol levels over the Atlantic (See Mann and Emanuel, 2006 )

    Here are some historical facts: The 1950-1999 average Atlantic hurricane activity was about 10 tropical and subtropical storms per year, about 5.9 of those reaching hurricane strength, and about 2.5 of those reaching major hurricane strength. But the averages of the last 20 seasons (1988 – 2007) have been 13 tropical and subtropical storms per year, about 7 reaching hurricane strength, and about 3 reaching major hurricane strength. In the last 10 seasons – 1998-2007 – those averages have been about 15 tropical and subtropical storms per year, about 8.1 reaching hurricane strength, and about 3.7 reaching major hurricane strength. This is an unmistakable upward trend in hurricane activity – the activity of the last 10 seasons is about 150% that of the historical average. Finally – it is not remotely necessary for a season to be as intense as 2005 in order for it to be very intense – after, all, 2004 (15 tropical storms, 9 hurricanes, 6 major hurricanes) had over 150% of the activity of an average season, yet was much less active than 2005 (28 tropical and subtropical storms, 15 hurricanes and 7 major hurricanes.)
    The abnormally high Atlantic hurricane activity of the last 10-15 years may or may not be due to global warming, but the less-than-2005 activity of the 2006-8 Atlantic hurricane seasons does not change the fact that the last 10-15 years have seen extra-ordinary hurricane activity. (In fact, if both 2005 and 2008 numbers are replaced the 1950-99 averages, the 1999-2008 period remains above the 1950-1999 averages on all 3 parameters.)

    Comment by llewelly — 9 Jul 2008 @ 6:31 PM

  184. Re: #178

    How is it cherry picking to point out that the consistent upward trend from 1977 on leveled off around the year 2000? Aside from the Pinatubo interruption in the early 90s, ENSO-corrected temperatures marched steadily upwards until 8-9 years ago. What explanation for this could there be? Simple “decadal variation” doesn’t work for me, because it gives no scientific cause for the halt in warming. If the warming was steady before, why wouldn’t it continue that way?

    Comment by Boyle — 9 Jul 2008 @ 7:30 PM

  185. “This is nonsense. The idea that ENSO is the only kind of intrinsic variability is silly. Look out of your window – and see planetary waves (of various wavenumber), the Madden-Julien oscillations, the NAO, the PDO, the PNA, the SAM, COWL, baroclinic instability, African waves, Antarctic dipoles etc etc. There is no shortage of variability in short term records. What would meteorologists have to talk about otherwise? – gavin”

    So Gavin, what you are saying is that some or all of these natural variables mentioned could have caused the flat trend since 2000? If that is the case, there should be some rationale for how they did so. In addition, what factor could natural variables have played in the warming from 1977-2000?

    [Response: In the long term trend, none of them. While the impacts of the various forcings do give a fit. Currently the expectation is for a trend, but natural variabilty will inevitably cause some periods to have a stronger than expected rise, and others a slower than expected rise. - gavin]

    Comment by Boyle — 9 Jul 2008 @ 7:36 PM

  186. #183 llewelly

    Thank you and yes, exactly my point, in response to FurryCatHerder.

    For the record, the comment you quoted was from FurryCatHerder, not me. My response to her was more in line with trend over events.

    How do you do that indent thing, I don’t want people thinking I’m saying what she is saying?

    My response as follows to FurryCatHerder (see above in #181):

    — I’m glad you reject all-or-nothing thinking, so stop thinking that way, or at least stop writing that way. You are confusing people. The above average ‘global’ TC season did materialize, it just didn’t all make the news due to the lack of landfall and proximity. It’s not weather events that you examine in climate, it’s the trend of weather events. You need to explain that to your friends. That is precisely why short term does not override long term trend analysis. maybe it confuses people because you did not explain that to them in an understandable manner? You can’t compare a trend ‘06 / ‘07 to ‘05, and call it climate. Yes people intuitively relate to weather rather than climate but you can explain it to them and as long as you don’t confuse them too much…

    Comment by John P. Reisman (The Centrist Party) — 9 Jul 2008 @ 7:37 PM

  187. John P. Reisman (The Centrist Party) #186:

    183 llewelly
    Thank you and yes, exactly my point, in response to FurryCatHerder.
    For the record, the comment you quoted was from FurryCatHerder, not me. My response to her was more in line with trend over events.

    My apologies. Thank you for telling me I had mistaken FurryCatHerder’s words for yours.

    How do you do that indent thing, I don’t want people thinking I’m saying what she is saying?

    I wrap the text in:
    < blockquote >
    < /blockquote >

    This works on wordpress blogs, on scienceblogs, and some other blogs. It does not work on blogger.

    Comment by llewelly — 9 Jul 2008 @ 9:17 PM

  188. Thanks for the response, Gavin. So basically, as long as the overall longterm trend is upward, global warming is still happening. I understand that idea, I just don’t understand how natural variables could have caused 2000-2008 to slow the warming. The PDO, NAO, and ENSO were all mostly positive from 2001-2007…and I’m sure there are other natural variables, but solar is the only one I can think of that has decreased in the past 10 years. Solar Cycle 23 peaked a little lower than the previous two cycles, but that doesn’t seem reason enough to me to cause less warming.

    Comment by Boyle — 9 Jul 2008 @ 9:29 PM

  189. Mr. John Reisman wrote at 1619 on the 9th of July in comment # 181:

    “When I here people make claims that are misleading in this argument (AGW) based on assumptions that are either not substantiated, or not substantiable, and knowing that millions if not billions of lives may be at stake. I kinda think those people should not hide behind monikers like furrycatherder and take full responsibility for their unsubstantiated claims and their ramifications. But it is your choice to hide behind your moniker.”

    Sir, I do not agree. There are more things on heaven and earth than are dreamt of in your statement. What if the poster in question is a victim of stalking or domestic violence ?

    More importantly, what does the strength of the argument have to do with the purported identity of the author ? If Prof. Arrhenius were to post here with his CO2 analysis under the name ‘Twirlip of the Mists’ would you dismiss his reasoning ?

    Comment by sidd — 9 Jul 2008 @ 10:09 PM

  190. I suppose the real worry is whether AGW has influenced the El-Niño recharge/discharge mechanism. ENSO warm episodes have dominated the last twenty years.

    The TAO project allows scientists to monitor warm water volume which tends to lead oceanic Niño indices by around 7 months, however…

    What we really need is real-time sub-surface sea temperature data for the entire planet (not just a slice of the equatorial pacific).

    Until then, I will be using December Antarctic sea-ice area as a surrogate measure of meridional up-welling.
    Decreased sea ice area during December preceded ‘94, ‘97, ‘02 and ‘06 warm episodes.

    The association between Sea ice, Antarctic oscillation, El Niño Southern Oscillation, is poorly understood.
    Indeed, it represents a major scientific challenge.

    Comment by David — 9 Jul 2008 @ 10:28 PM

  191. In re 183:

    What a convenient way to avoid admitting that despite the 2006-7 Atlantic hurricane seasons being less active than 2005 , there is nonetheless a strong upward trend in Atlantic hurricane activity – which, while perhaps not caused by global warming, shows a correlation with rising sea surface temperatures in the Atlantic, and with changing aerosol levels over the Atlantic (See Mann and Emanuel, 2006 )

    Well, I didn’t address whether or not there was one, I only pointed out that using weather forecasts to explain climate change is a bad idea. I then presented the past two years’ “above average” hurricane season forecasts (which both missed for Atlantic basin storms when compared to ’05) as examples of what not to do if one wants to convince others that climate change is real.

    As regards the uptick in storms, yes, there has been one. And there was one just like it in the 1950′s and another just like it in the 1890′s. Here is a nice chart from NOAA if you’d like to check it out. I’m going to go out on a limb and forecast a period of declining tropical storm intensity in the Atlantic basin over the next few decades, with another peak just in time for me to be dead and buried.

    Comment by FurryCatHerder — 9 Jul 2008 @ 10:54 PM

  192. Heikki T and others…

    There is proof to more than 99% confidence that HUMAN CO2 emissions are driving the current rise in temperature. The analysis is pretty clear and indisputable. see: (read the comments too)..

    Anthropogenic Global Warming is Absolutely Occurring
    http://autismnaturalvariation.blogspot.com/2008/06/anthropogenic-global-warming-is.html

    Comment by paulm — 10 Jul 2008 @ 1:25 AM

  193. 183 llewelly

    And here is the analysis that proves with more than 99% confidence that the frequency of name storms of the Atlantic is linked to surface temperature.

    Hurricanes and Temperature are Indeed Associated
    http://residualanalysis.blogspot.com/2008/06/hurricanes-and-temperature-are-indeed.html

    here

    It is pretty irrefutable!

    Comment by paulm — 10 Jul 2008 @ 1:41 AM

  194. re: 184.

    Sigh. 1. Look at the 30-year trend. At least. 2. There are still natural influences (e.g. La Nina, El Nino) on the short-term trend.

    Comment by Dan — 10 Jul 2008 @ 4:41 AM

  195. Brian Klappstein writes:

    “…The characteristic time scale for climate or climate change is 30 years….”

    (Barton Paul Levenson)

    Says who?

    The World Meteorological Organization. Did you actually read what I posted?

    Comment by Barton Paul Levenson — 10 Jul 2008 @ 7:05 AM

  196. Fred writes:

    The UAH data is presented monthly. If we choose to calculate a regression based on longer periods all we will do is lose information.

    You’re confusing noise with signal.

    Comment by Barton Paul Levenson — 10 Jul 2008 @ 7:11 AM

  197. Fred #179

    Yes, the temperature is not random: it depends on many varying factors. However, if we don’t care about those factors they are indistinguishable from noise.

    E.g. the temperature this morning had nothing to do with the temperature three weeks ago.

    The temperature this morning has something to do with the climate (e.g. summer). But the effect of it being summer is very much lower than the variability due to , say, cloud cover. But if we take the temperatures in the morning of the last 30 10th July then the cloud (which doesn’t vary depending on date) will cancel itself out in very much the same manner as “noise”.

    If I use every 10th year, I’m in lock step with the solar constant which varies over that time. If I pick the last six years to add, the changes from cloud cover may still be too long. If I take the last 1,000 years, I’ll miss out any signal that takes

    Comment by Mark — 10 Jul 2008 @ 8:39 AM

  198. Re: #191 (FurryCatHerder)

    As regards the uptick in storms, yes, there has been one. And there was one just like it in the 1950’s and another just like it in the 1890’s. Here is a nice chart from NOAA if you’d like to check it out.

    Are you sure about that? Have you done an analysis of the data, or are you just drawing a conclusion based on visual inspection of the graph?

    I’m a mathematician specializing in time series analysis. To my experienced, professional eye it looks like the most recent period shows a significantly higher level of activity than any previous part of the data record, including the 1950s and 1890s — those time periods were not “just like it” at all. But even though I’m a professional with decades of experience at this, I can’t be sure because I know that visual inspection of a graph can be suggestive but is easily misleading.

    I suggest that it’s folly to draw conclusions such as the one you’ve stated without some analysis to back it up. I further state as fact that conclusions based on visual inspection — even for those of us who are experienced at the analysis of such data — are untrustworthy.

    Comment by tamino — 10 Jul 2008 @ 8:54 AM

  199. paulm (193) says

    … proves with more than 99% confidence that the frequency of name storms of the Atlantic is linked to surface temperature.

    Yet there is a large respected and credentialed group (including some of RC moderators if memory serves) that says otherwise. Makes your “99% proof” hyperbole at best. (Though a number of the above would claim an increase in intensity of storms.)

    Plus your reference in 192 is prima facie miles away from a universal “99% proof” of AGW.

    Comment by Rod B — 10 Jul 2008 @ 10:35 AM

  200. Tamino (198), you’re being too excessive. To say nobody can rightly look at the chart and reasonably (albeit tentatively) draw a conclusion that the three periods mentioned are roughly similar, is just nonsense. But your take (admittedly very tentative) that one of the periods is significantly greater and the others are not … like it at all is logical (emphasis mostly mine)? Is it your experience (which I am in no way minimizing) that the numerical analysis result will turn an overview completely on its head and make it completely different? If one “calls ‘em as he sees ‘em”, is he highly likely to be 180 degrees wrong?

    Comment by Rod B — 10 Jul 2008 @ 11:29 AM

  201. #194

    Yes, I am looking at the 30 year trend. And the first 20 years (1978-1998) show a steady climb upwards, interrupted only by a volcanic eruption. Then the last 10 years the upward trend disappears. The whole 30 year period has been dominated by +PDO and El Nino ENSO, natural factors that favor warmer temperatures. So what changed in the past 10 years to stop the temperature rise? I still haven’t seen that question answered.

    Comment by Boyle — 10 Jul 2008 @ 11:37 AM

  202. #190

    Yes, David, El Nino has dominated the past 30 years. But La Nina dominated the previous -PDO period from 1946-76. And then before that, El Nino dominated the 1925-45 period. So there really isn’t anything too unusual about El Nino dominating this latest +PDO phase.

    Comment by Boyle — 10 Jul 2008 @ 11:40 AM

  203. “…The World Meteorological Organization. Did you actually read what I posted?…”

    (Barton Paul Levenson)

    It was a rhetorical question, I’ll well aware of the orthodoxy on the definition of climate change, I just don’t agree. See my somewhat sarcastic response to another poster at #180 or so.

    Regards, BRK

    Comment by Brian Klappstein — 10 Jul 2008 @ 12:37 PM

  204. Rod, enough with the straw men.

    You made up something Tamino did not say — a caricature, distorted, incorrect — and attribute it to him, and then argue with it.

    Read what he wrote. Get real.

    He’s trying to teach you one of the hardest lessons everyone learns who passes Statistics 101.

    And you’re failing to learn it.

    If you don’t understand this you won’t understand climate research.

    Comment by Hank Roberts — 10 Jul 2008 @ 12:55 PM

  205. Re: #199 (Rod B)

    Visual inspection (looking at the graph) is one of the best ways to gain insight — I often scold scientists for failure to appreciate the importance of actually looking at the data (you might be surprised how often researchers simply run the data through a “black box” without actually looking at it). The eye/brain combination is one of the most potent pattern-recognition systems ever. But it’s very far from infallible, and what a non-analyst “sees” is usually different from what an experienced analyst sees; years of experience combining visual inspection with numerical analysis actually improves the reliability of visual inspection.

    While visual inspection is perhaps the most powerful general-purpose pattern recognition method, it may also be the most susceptible to “false alarms.” So, conclusions based on visual inspection alone are suspect, even those coming from an experienced analyst. Only the combination with numerical analysis can provide the level of confidence needed to make assertions.

    Analysis will rarely make the results “do a 180″; I seriously doubt that analysis will indicate the apparent increases in the 1950s and 1890s are actually decreases! But you’d be surprised (very surprised, I’ll venture) how often analysis makes the result “do a 90.” The increase you thought couldn’t be by accident turns out to have no significance at all, or the blip you were sure is meaningless turns out to be an undeniable physical change.

    If you want to know how the recent decades compare with previous ones, I’d suggest acquiring the data and helping yourself with some basic analysis. One of the simplest is to smooth the data, and one of the simplest and most reliable methods of doing so is to compute running averages. It’s also a very accessible method, since ExCel will compute (and graph) running averages. Of course, one then has to contend with the issue of how long a time period to average, and how to interpret the results of that analysis. But it will surely provide more information, and will help assess whether the modern era is “just like the others” or something really different.

    To the lay readers I say: don’t trust what the graph looks like without some analysis to assist your evaluation. To the scientist I say: don’t trust analysis without careful and detailed visual inspection. And to both: it always helps to get a 2nd opinion (but try your best not to bias that opinion by expressing your belief or your preference).

    Comment by tamino — 10 Jul 2008 @ 1:15 PM

  206. Boyle, #201.

    No, don’t look IN the 30-year period. ADD UP each thirty year period.

    Saying that the last 10 years is flat is what WEATHER is happening. 10 years can’t tell you squat about climate.

    So, add up the last 30 years average temperatures.

    Add up the 30 before that.

    And the 30 before that.

    Go back 210 years.

    Plot.

    See a trend.

    PS “we’re in a cycle” a’ la Steven Goddard is silly: why is there a 15-year cycle THIS last 15 years but not before then? Because nobody has ever shown any, y’know, *cyclic* figures before that showing the same periodicity.

    Maybe those saying have made up whatever period fits the bit they are showing. But that’s not science. Heck, it’s not even honesty.

    Comment by Mark — 10 Jul 2008 @ 1:36 PM

  207. #189 sidd

    If Prof. ‘Twirlip of the Mists’ was trying to represent unsubstantiated opinion as fact (especially in the face of solid evidence that contradicts his assertion), yet, I would dismiss his reasoning.

    My point is simple, if she is going to say she represents the truth, then she should tell us who she is. She is making definitive claims that are simply wrong. Any kindergarten student can probably figure out that 1.9 is larger than .3 if you show them the difference.

    As to the poster in question being a victim of stalking or domestic violence? Maybe. Personally, I see her driving downtown in Austin, TX in a corvette (when she wants to strut) or greener vehicle when she wants to show how green she is, feeling pretty confident she has a handle on pretty much everything.

    The main point is I would not have asked her name if she had answered my question and shown us here evidence that proves she is at the very least reasonably right about her claim that this is all solar. Instead she makes vague references to solar cycles that prove absolutely nothing because they don’t have context, nor relevance to known values of forcing of solar and AGW GHG’s.

    She continues to ignore the forcing levels of current AGW estimated around 1.9 W/m2 and still won’t explain to us why .3 is not less than 1.9 W/m2.

    Said another way, we don’t need sunspots to keep warming, it just means the warming will be a little slower, and when sunspots return, the warming will be a little faster, then compounded by positive feedbacks as well. If FurryCat can lay some concrete in here, I’m sure we’d all be very impressed.

    Comment by John P. Reisman (The Centrist Party) — 10 Jul 2008 @ 2:00 PM

  208. #200 Rod B

    I take Taminos post to mean that correlation does not mean causation like in the GCR’s argument that FurryCat presented on the aa index http://www.realclimate.org/index.php?p=42 saying that it matches, so it must be…

    But according to FurryCatHerder I don’t know what that means; but I don’t think Tamino is being excessive, I think he is being considerate of context and relevance. But, hey, that’s just my opinion, and anyway, I’m a putz, from what I hear.

    Comment by John P. Reisman (The Centrist Party) — 10 Jul 2008 @ 2:14 PM

  209. Rod,
    Read what Tamino said in #205. It is important. When you get a dataset, the first step is exploratory data analysis–plotting data in different ways, comparing it to known distributions, looking for periodicities, trends, etc. The human eye is one of the most powerful tools for spotting such trends. Hundreds of millions of years of evolution have sculpted a tool with tremendous sensitivity to patterns, but it takes statistical analysis to determine if the patterns are really there.

    Comment by Ray Ladbury — 10 Jul 2008 @ 2:19 PM

  210. Boyle (201) — Here are the decadal averages from the HadCRUTv3 global temperature product:

    http://tamino.files.wordpress.com/2008/04/10yave.jpg

    Comment by David B. Benson — 10 Jul 2008 @ 2:43 PM

  211. As to Sir William of Ockham, you’ve been watching too many movies. Ockham’s Razor (from Ockham, England) is, Entia non sunt mulltiplicinda praetor nesectita tatum, by my recollection. And that means entities should not be multiplied more than necessary. The Jodie foster interpretation was, I would say, a loose interpretation, but not too uncommon. The idea of all things being equal the best solution is the most simple does not apply to your argument

    It is unfortunate that Ockham’s quite reasonable KISS admonition has been so widely misunderstood as “the simplest explanation is most likely to be correct.” Keeping your theories as simple as possible is an excellent rule of thumb for scientific investigation, because it generally takes much less data to exclude a simple model that a complex one, so working from simple to complex is the most efficient way of progressing through a series of possible models/explanations. Turning this from a practical admonition about model-building into an assertion about probability is utterly without foundation, and flies in the face of a long, long scientific history of simple models being supplanted by more complex one.

    Comment by trrll — 10 Jul 2008 @ 2:47 PM

  212. Mr. Reisman wrote on the 10th of July, 1400:

    “if she is going to say she represents the truth, then she should tell us who she is.”

    i do not see the syllogism. i might say that i represent the furry aliens from Tralfamadore, and you are free to believe or disbelieve me according to your view of supporting evidence, if any. Such supporting evidence has nothing to do with the name i chose to post under.

    similarly if i claim that statistics governing fermions differ from those governing bosons, the truth of my statement is not affected whether i post this as Satyendranath or as Bozo. Else discussion degenerates into ad hominem and argument from authority.

    I am deeply disinterested in the identities of posters, and very much against forcing participants to reveal their names before their arguments are considered. But this is getting very far afield, so i will not object if our gracious moderators choose to delete this thread entirely.

    To drag the discussion back to climatology, I have a question. I am aware of some data measuring heat fluxes into deep ocean. Are there data accurate enough to tell if these fluxes have changed appreciably over, say, the last three decades ? And more sharply, is there any evidence that these fluxes are at all correlated with AMO/PDO/… ?

    Comment by sidd — 10 Jul 2008 @ 3:07 PM

  213. Hank (204), while I shortened it for essentials, I came close to quoting Tamino verbatim. What is it you think I should read?

    Comment by Rod B — 10 Jul 2008 @ 3:09 PM

  214. Tamino (205), While I still maintain your assessment of the graph in question is a gross over-reaction and incorrect, and FurryCatHerder’s point has merit, I do agree with almost every word of your 205 post.

    Comment by Rod B — 10 Jul 2008 @ 3:19 PM

  215. #209 sidd

    Luckily this is America and you are free to be disinterested in anything you like.

    But your disinterests are not my disinterests. That’s the beauty of individuality and freedom of thought. Please feel free to think as you wish and not let my interests impede your thoughts.

    Comment by John P. Reisman (The Centrist Party) — 10 Jul 2008 @ 3:26 PM

  216. #206

    Mark,

    Yes, and I find ten years a long enough time to distinguish between “noise” and “trends”. Why? Because there are no prior ten year periods during the warming signal that can be equated with this one. If it is noise, it should appear periodically. Show me another flat ten year trend during a +PDO/+ENSO phase the past 100 years. In addition, there should be some sort of scientific explanation for the “noise”…if there is not, then can we not discount the previous ten year trend (1988-1998) as just noise as well? We must have some faith in the accurracy of global temperature readings, or else there is no way to be certain of any trends.

    Comment by Boyle — 10 Jul 2008 @ 4:38 PM

  217. In re 205:

    I know what to look for to know if a single outlier, or small number of points, represents a trend or an outlier(s). I’d be surprised if a 10 year moving average failed to show anything but what the graph appears to show. I don’t have time at this precise moment to do that, but I’d be surprised if a 10 year moving average even showed a 45 degree turn, much less the dreaded 90 or 180 degree variety.

    But I’ll make my point to you that I made earlier to Reisman — whatever natural trends caused those cycles through 150 or whatever years of industrialization has to still be at work. The alternative is that they are purely chance, and chance seldom makes pretty charts with nice cycles.

    Comment by FurryCatHerder — 10 Jul 2008 @ 4:41 PM

  218. In addition, Mark, doesn’t it seem somewhat arbitrary to label the latest ten-year period as “noise”, and yet we seem to accept any other ten year period as indicative of the overall trend?

    [edit - don't just repeat yourself all the time - it's dull]

    Comment by Boyle — 10 Jul 2008 @ 4:49 PM

  219. Boyle (218) — I left this for you on another thread, but you seemed to have wandered over here.

    Here is the decadal averages of the HadCRUTv3 global temperature product:

    http://tamino.files.wordpress.com/2008/04/10yave.jpg

    Study it this time, please.

    Comment by David B. Benson — 10 Jul 2008 @ 5:25 PM

  220. re: 218. 1998 was an exceptionally warm year due to the AGW and the additional influence of the historically strong El Nino on top of it. Using 1998 as a reference point for a any trend is classic cherry-picking of the data. The long-term trend is unequivocal.

    Comment by Dan — 10 Jul 2008 @ 5:25 PM

  221. “Using 1998 as a reference point for a any trend is classic cherry-picking of the data. The long-term trend is unequivocal.”

    This is false. The 1998 El Nino was immediately followed by a long La Nina. There were 7 El Nino/La Nina cycles in that ten year period. As Gavin’s ENSO adjusted data shows, The decadal flat trend is not due to ENSO or any cherry picked ENSO endpoints.

    http://reallyrealclimate.blogspot.com/2008/07/gavin-schmidt-enso-adjustment-for.html

    So far no one has suggested any other observed natural variation that explains the decade long flat trend.

    [Response: Well, discarding all the data that don't support your point is also a classic cherry pick - what happened to the GISTEMP or NCDC? - gavin]

    Comment by Tilo Reber — 10 Jul 2008 @ 5:53 PM

  222. Re: Accumulated Cyclone Energy (ACE) graph for the Atlantic basin

    As regards the uptick in storms, yes, there has been one. And there was one just like it in the 1950’s and another just like it in the 1890’s. Here is a nice chart from NOAA if you’d like to check it out.

    I tried to explain that visual inspection of a graph can be very misleading, and that my professional eye indicated a different conclusion, but that I wouldn’t trust it because it wasn’t coupled to any analysis. I emphasized that this opinion isn’t a knee-jerk reaction, it’s based on decades of experience. I also suggested at least using some analysis, something as rough but simple as moving averages, to get more insight.

    While my thesis garnered only agreement, regarding the specific case at hand it seems I haven’t persuaded those who believe the modern era is “just like” the 1950s and 1890s to give serious consideration to the possibility that it might not be the case. Instead I hear “I still maintain your assessment of the graph in question is a gross over-reaction and incorrect” and “I’d be surprised if a 10 year moving average failed to show anything but what the graph appears to show. I don’t have time at this precise moment to do that…”

    The data are available here. I calculated 11-yr moving averages. The early peak moving average is 124.9 for the 11-year period centered at 1892; the mid-century averages peak at 122.4 centered at 1953; the lowest value in the trough between them is 58.9 centered at 1915. Peak-to-trough amplitude for the change in 11-yr average for this period of time is therefore 66.0.

    The recent peak is 156.9 for the 11-year average centered at 2000. This is 32.0 higher than the highest previous peak, or 48% of the preceding peak-to-trough amplitude greater than the previous maximum.

    In fact, the average for the 11-yr period centered on 1999, which excludes the phenomenal 2005 Atlantic hurricane season, is 137.2, still higher than the preceding peak by 12.3, or 19% of the peak-to-trough amplitude.

    More sophisticated smoothing methods indicate an even greater difference between recent activity and previous peaks.

    Comment by tamino — 10 Jul 2008 @ 6:39 PM

  223. Tamino,

    No, I don’t think the modern era is “just like” anything.

    That would be called “all or nothing thinking” on your part.

    Could you answer me a simple question — why do you do that? Why does it seem that otherwise smart people can’t comprehend a periodic signal summed with a linear signal to produce a monotonically increasing periodic signal?

    Is this some kind of really difficult thing to grasp? Like, y = mx + b and y = sin(x) somehow don’t go together?

    Comment by FurryCatHerder — 10 Jul 2008 @ 8:05 PM

  224. Re: #223 (FurryCatHerder)

    No, I don’t think the modern era is “just like” anything.

    Here’s what you said in #191:

    As regards the uptick in storms, yes, there has been one. And there was one just like it in the 1950’s and another just like it in the 1890’s.

    The words are yours (the emphasis is mine). Yet you want to accuse me of “all or nothing thinking” and ask “why do you do that?”

    You’re not just being absurd. You’re being dishonest.

    Comment by tamino — 10 Jul 2008 @ 8:45 PM

  225. Tamino,

    “Like” is not “exactly the same value”, which is what you complained about. That, while going up and down — which you seem to comprehend the ACE value does — you then said “Ah ha! The high is higher!” Up and down is … up and down. That’s periodic part — “up” like before, “down” like before.

    It’s the “down” part you and Reisman have a problem with. [edit]

    Please — let’s keep all the context together. It went up, it’s going down. Yes?

    Feel free to just, you know, agree with the obvious. 2008 is going to be a less active year in the Atlantic basin than 2005, 2006 and very likely 2007.

    [edit]

    [Response: I don't know why this thread seems to have brought out the most pedantic and tedious aspects of conversation, but it is tiresome. Please focus on substance rather than on who said what when. - gavin]

    Comment by FurryCatHerder — 10 Jul 2008 @ 10:06 PM

  226. Gavin:
    “what happened to the GISTEMP or NCDC?”

    Regarding GISTEMP, in the last decade it is diverging from RSS, UAH, and HadCrut3 at a rate of about .13 C per decade. The divergence is more than half the supposed .2 C decadal trend due to AGW. It fails to cover much of Africa, Northern Canada, and Greenland, and the extrapolations at the poles would seem to be dubious in light of the Antarctic cooling. That along with the failure of the network to follow it’s own quality control standards, hinged adjustments that adjust rural sites from the past down, weighting urban station adjustments to rural stations such that stations from 500 to 1000 km use the same range as those from 250 to 500 km, etc, give me little faith in GISTEMP.

    But, I’m willing to accept that there is a chance that the others are wrong and that GISTEMP is more correct, and so I will make my statement another way. If the HadCrut3, RSS, and UAH trend lines are the correct ones, and if ENSO adjustments to RSS and UAH lead to similar results as the adjustments to HadCrut3, then we do not seem to have an understood culprit among the elements of natural variation on whom we can blame the absent warming.

    Fair enough?

    [Response: No. First off you ignored NCDC completely, second HadCRUT3v uses basically the same input data as the other two. GISTEMP does not control any of the station issues you think are important, and you completely ignore the large structural differences in the satellite records. I'm not claiming that I know which (if any) approaches are correct, but picking just the ones that agree with a pre-determined idea of what you want to see is not 'fair enough', it is cherry picking. You have to use all the relevant data. - gavin]

    Comment by Tilo Reber — 10 Jul 2008 @ 11:25 PM

  227. If something as simple as a volcano can cut temperature so severely isnt human replication of this possible?

    Comment by Adam M — 11 Jul 2008 @ 3:39 AM

  228. Adam M (227), In theory you are right but the unintended consequences (such as drought) would likely be severe. There is also the problem that the effects of stratospheric SO2 injection only last a couple of years while the effects of CO2 last hundreds of times that long. These issues have been discussed here several times. Search the site for: “geoengineering”.

    Comment by Arch Stanton — 11 Jul 2008 @ 8:49 AM

  229. Re 219 Thanks david. That is a great chart. Now 1t looks to me that since 1900 you have one 10 year peroid with a
    downward trend. And that ten year peroid just happens to
    be the peroid that is going to be adjusted upward when
    the bucket/inlet problem gets fixed.

    So go back 100 years, excluding those peroids where volanoes spiked the tempature down, and excluding those peroids where we have data that is still being corrected
    ( the bucket peroid) can we find some 10 year peroid that is flat or down. I dont know. I’ll have to look.
    And when we find one can we tie to an actual weather cycle rather than weather armwaving. again, open question. I dont know. might be fun to look.
    Please note it won’t make AGW false, it will just be an interesting thing to understand.

    Comment by stevenmosher — 11 Jul 2008 @ 8:53 AM

  230. David B. Benson #219

    Layman’s question – I’ve looked at your chart (and 1000 others). What is it that explains the warming from ~1920 – ~1940 that does not explain warming since mid century?

    John Reisman – “1950 to 1978′ (1942 to 1978) temps were likely due to aerosol pollution.” OK, then what portion of warming since 1978 is due to the reduction of aerosols, soot & pollution rather than AGW?

    Thank you both.

    Comment by Radar — 11 Jul 2008 @ 9:57 AM

  231. Is there any way to get RAW data before everyone does their tricks with the data, like GISTemp data WITH the outliers kept in, or HadCRUT before data made up data from the artic and other areas get added. It really would be interesting to see just the RAW DATA plotted out and then compare the plots to what keeps being shown.

    [Response: Yes. Download the GHCN data. - gavin]

    Comment by T Siefferman — 11 Jul 2008 @ 12:31 PM

  232. “Layman’s question – I’ve looked at your chart (and 1000 others). What is it that explains the warming from ~1920 – ~1940 that does not explain warming since mid century?”

    Have you looked at this?
    http://en.wikipedia.org/wiki/Image:Climate_Change_Attribution.png

    Between 1900-1940 there is notable increasing in solar activity that isn’t present any time after that. There is also a prolonged period of relatively little volcanic activity. (Volcanic activity has a cooling effect) There is also a drop in aerosol cooling through the 30’s which could play a role as well.

    “ OK, then what portion of warming since 1978 is due to the reduction of aerosols, soot & pollution rather than AGW?”

    Warming caused by a reduction in aerosols can still be AGW. All aerosols do is hide warming for a time, and most of the warming they are currently hiding is almost certainly anthropogenic in nature. Aerosols have been increasing but are not doing so as fast as CO2 levels, so they balanced CO2 emissions for a time but in the mid 70’s CO2 starts to dominate.

    Comment by L Miller — 11 Jul 2008 @ 12:58 PM

  233. #231 T Siefferman:

    When you speculate that data is “made up”, it’s axiomatic that someone (me, in this case) is going to ask why you believe it’s made up? Can you show how this is so? Next, how is it made up? Are numbers drawn from a hat? Darts thrown at a dartboard?

    I believe if you think about it carefully, you’ll realize you’ve been told that data is “made up” and you’ve accepted what you’ve been told without further consideration.

    Further, it’s likely that if you picture to yourself a scientist throwing darts at a dartboard, carefully recording the output and then proceeding to stick his/her neck on a chopping block by publishing the results, you’ll come to understand what an absurd idea has been planted in your noggin.

    Comment by Doug Bostrom — 11 Jul 2008 @ 3:18 PM

  234. L. Miller:

    Thanks. I’ve seen the chart and your commentary about solar activity 1900-1940 helped me see that.

    The chart is not so great; It ends in 1995. And it shows aerosols continuing to force temperature down.

    That is a problem because despite your thinking the contrary, aerosols have not been increasing, they are “at historic lows” for some time (~2000). So if you’re going to support the aerosol cooling masking AGW theory, it makes it more difficult to explain the lack of warming that coincides with these “historic lows” does it not?

    [Response: Aerosols are only at 'historic lows' in the US and Europe. They are at historic highs in Asia - the net effect relatively to previous decades is currently uncertain. - gavin]

    Comment by Radar — 11 Jul 2008 @ 3:34 PM

  235. #232 L Miller:

    Between 1900-1940 there is notable increasing in solar activity that isn’t present any time after that. There is also a prolonged period of relatively little volcanic activity. (Volcanic activity has a cooling effect) There is also a drop in aerosol cooling through the 30’s which could play a role as well.

    True, but I would make the reservation that our knowledge of this solar increase is highly uncertain. It was adjusted downward substantially in AR4.

    Furthermore see Figure 9.5a in the AR4 WG1 report. You see that the peak around 1940 pushes the top edge of the ensemble of model simulations. This suggests that a substantial part of the 1920-1940 trend is natural variability in the one realization that is the measured temp curve. Note that for later years, this black curve lies much closer to the ensenble average.

    Finally note the accuracy of the measurements-based curve, which degrades before 1940 due to lower station density, among other things. See Brahan et al. 2006.

    Comment by Martin Vermeer — 11 Jul 2008 @ 4:08 PM

  236. Gavin:
    “You have to use all the relevant data.”
    Gavin:
    “HadCRUT3v uses basically the same input data as the other two.”

    I am using all of the data. I’m simply not using all of the different adjustments of the same data. And I see no reason why I should. I suppose that you could theorize that by using different peoples adjustements that the errors will cancel each other. But of course that’s not verifiable. I also don’t see you making much use of UAH or RSS. So I think that the accusation of cherry picking is unfounded.

    And lastly, you have shifted the topic from one that you do not want to deal with, mainly how to explain the decadal flat trend, to one where you can bicker about data set choices.

    [Response: You miss the point entirely. The other two datasets don't have a 'flat' trend. Thus your flat trend is not a robust result, and so asking me to explain something that might not even be true is silly. However, the variability in the system is undeniable, and it's expression the global mean temperature clear. As for my not using the satellite data, that is untrue. I've used it when it was relevant. Despite the current fashion for thinking them equivalent to the surface data, I do not confuse the lower troposphere with the surface. They might be related, but as many papers have shown (including Santer et al (2005)) showed clearly, they are not the same. Should I use the satellite data, I would use both records (and maybe Vinnikov and Grody as well) because there are clear structural uncertainties in those products that should not be brushed aside. - gavin]

    Comment by Tilo Reber — 11 Jul 2008 @ 9:54 PM

  237. Reality check.

    Once again we suffer from people drawing conclusions (in this case, “flat trend”) based on visual inspection of a graph with no numerical analysis. It’s particularly problematic in this case because not only is the noise not white, it isn’t even AR1 (the usual model used to correct for autocorrelation); the AR1 correction to trend analysis underestimates the uncertainty because the autocorrelation coefficients higher than the 1st decay more slowly than that.

    So I computed the trend rate from 1998 to the present (a wee tiny bit more than the last decade), for both ENSO-corrected data series, using the complete formula for autocorrelation correction to linear regression, modeling the AR coefficients as rho_j = rho_1 * alpha^(j-1) (which gives a much better fit to the AR coefficients than the AR1 model rho_j = (rho_1)^j). The results: for ENSO-corrected HadCRU: +0.0014 +/- 0.0172 deg.C/yr (2-sigma); GISS: +0.0134 +/- 0.0180 deg.C/yr. The 95% confidence intervals are, for HadCRU: -0.0158 to +0.0186; GISS: -0.0046 to +0.0314. Both ranges include the oft-quoted modern trend rate +0.018 deg.C/yr.

    Of course my model for the autocorrelation coefficients is only an approximation and the numerical estimates of its values are uncertain. But that only ADDS to the uncertainty in the trend estimate, making the error ranges even larger.

    The upshot is that when you take autocorrelation into account in a more rigorous way than is usually done, the ENSO-corrected data for the last decade (for *both* GISS and HadCRU) are perfectly consistent with an uninterrupted continuation of the 30-year trend. Yes, they’re both consistent with a trend rate of zero as well — but given the huge uncertainties, this merely underscores the utter folly of making pronouncements about the trend based on a mere 10 years of data.

    It REALLY IS a mistake to draw conclusions about trends (or reversals of same) based on small samples, especially when the signal-to-noise ratio is small and the autocorrelation is both strong and complicated. “Your flat trend is not a robust result” is an understatement.

    Comment by tamino — 12 Jul 2008 @ 1:18 AM

  238. Re #234 Radar

    Here’s a more up to date illustration of the forcings driving Earth’s temperature changes, including the estimated trend in aerosolic cooling contributions:

    http://pubs.giss.nasa.gov/docs/2005/2005_Hansen_etal_1.pdf (see Figure 1)

    http://pubs.giss.nasa.gov/docs/2007/2007_Hansen_etal_3_small.pdf (see Figure 5)

    If you can get hold of this article, it also illustrates the forcings of aerosolic components and greenhouse gases.

    V. Ramanathan and G. Carmichael (2008) “Global and regional climate changes due to black carbon” Nature Geoscience 1, 221 – 227

    http://www.nature.com/ngeo/journal/v1/n4/abs/ngeo156.html

    If you can’t access that paper you can read some of the relevant data in Ramanathan’s testimonial to the Wegman hearing:

    i.e.: http://oversight.house.gov/documents/20071018110734.pdf

    In their Table 2, Ramanathan/Carmichael diagram the contributions from various man-made greenhouse gas (GHG) and man-made aerosols, considering the effect on both the atmosphere or surface:

    all GHG’s (CO2, methane, N20, halons, ozone):
    atmosphere +1.4
    surface +1.6
    total +3.0 W/m2

    CO2:
    atmosphere +1.0
    surface +0.6
    total +1.6

    black carbon (BC):
    atmosphere +2.6
    surface -1.7
    total +0.9

    non BC man-made aerosols:
    atmosphere +0.4
    surface -2.7
    total -2.3

    There are other bits and pieces that address your question in part. Focussing on the Arctic, a recent paper examines the solar irradiation at the surface (“global dimming”/”brightening”) presumably as a result of atmospheric aerosols. Measured in stations in the high northern latitudes in N. Europe/Arctic, the “surface solar irradiation” averages around 115 W/m2 in 1960 (note that fewer stations were monitored during this period) and decreases progressively to reach a low near 103 W/m2 around 1987 from which it recovers a bit to reach a level near 106/107 W/m2 now, still well below the levels of the early 1960′s. (see their Figure 3).

    http://folk.uio.no/jegill/papers/Stjern_etal_2008_IJClim.pdf

    and a couple of other papers (I’m sure there must be more!) address changes in surface solar irradiation in Arctic regions associated with changes in atmospheric aerosol content.

    S. T. Weston et al (2007) Interannual solar and net radiation trends in the Canadian Arctic Journal Of Geophysical Research 112, D10105

    Stanhill G (1995) Solar Irradiance, Air-Pollution And Temperature-Changes In The Arctic, Philosophical Transactions Of The Royal Society Of London Series A- 352 247-258

    abstracts/extracts:

    [Weston et al (2007)]
    Although the trends are not explicitly linear, both data from Alert and Resolute Bay show an overall decrease in K↓ over the past half-century. Data from Alert shows a decrease of 2.25% of the daily mean CI, and Resolute Bay shows a decrease of 2.50% of the daily mean CI per decade. Although further data are needed to tell conclusively, it also appears that both sites show a recent recovery over the past decade. As is speculated by other authors [e.g., Stanhill, 1995; Lohmann et al., 2004; Che et al., 2005], it is most likely that changes in atmospheric constituents (aerosols and/or greenhouse gases) are the major cause. Further study in this area is definitely warranted.

    (K↓ is solar radiation; CI is daily “clearness index”)

    [Stanhill (1995)]
    “A highly significant decrease in the annual sums of global irradiance reaching the surface of the Arctic, averaging 0.36 W m(-2) per year, was derived from an analysis of 389 complete years of measurement, beginning in 1950, at 22 pyranometer stations within the Arctic Circle. The smaller data base of radiation balance measurements available showed a much smaller and statistically non-significant change.
    Reductions in global irradiance were most frequent in the early spring months and in the western sectors of the Arctic, coinciding with the seasonal and spatial distribution of the incursions of polluted air which give rise to the Arctic Haze.

    Comment by Chris — 12 Jul 2008 @ 10:10 AM

  239. I am still trying to work my around the different facets of climate science and have a few questions I would like answers to:
    As the net energy levels increase due to AGW (less going out than coming in) is this causing a global mean increase in wind speed? If this is the case would this actually result in a decrease in SST due to increased evaporation?
    The last question, and probably impossible to answer, is how much of the heat energy is under the oceans and is it possible to extrapolate a mean ocean temperature and if so the warming trend?

    Comment by Mike Keep — 15 Jul 2008 @ 4:09 AM

  240. Gavin,

    A few years ago (January 2004) I posted a comment that the temperatures seemed to be warming more than the statistics indicate. In summary, your reply was that the statistics are likely correct and that the impression was the result of some unusually warm weather. I accepted your reassurance at the time.

    However at the risk of seeming to nag you, this winter where I live (on the Monaro Table land in New South Wales, Australia) is again fueling my suspicion that the warming is stronger than the statistics are saying.

    The dam on my property for example. Prior to 4 years ago it froze over more than 5 times per winter. Three years ago it froze over 3 times, last year twice, this year none so far. Prior to 8 years ago snow falls down to 700 meters were not unusual in this area, last year it fell down to about 900 meters for one day only, this year it was down to 1000 meters for 1/2 a day.

    My observations also seem to correlate in nearby regions, see: http://www.smh.com.au/news/national/snowman-would-be-stretching-it/2008/07/09/1215282928012.html

    Local old time residents to this area tell me that a solid week of snow could be expected on the ground where I live and the local mountain would be snow capped for a month. In addition, strong cold fronts could bring snow right up until the end of December. They recall three Christmas day snow falls (over 50 years). There is no way that would happen now.

    It is as though the Southern Ocean has warmed enough to take the bite out of the cold prior to the wind reaching Australia.

    The Statistics however are saying that it is only about 1 degree C warmer. That seems like rubbish, 5 degrees C warmer seems to be the more realistic number (over the 30 year average).

    My specific question to you is: is it possible that the temperature measurements are somehow under-estimating the temperature increase?

    Cheers…

    Comment by Lawrence McLean — 19 Jul 2008 @ 9:42 PM

  241. Please advise if the latent heat of ice cooling can come into this on a planetary scale. If ice is melting, shouldn’t the increase in mean global temperature slow or stop while ice is melting, due to the energy absorbed by the melting process?

    Comment by Rob — 18 Sep 2008 @ 10:11 PM

  242. So, if la nina truly decreases the observed temperatures, does the heat dissolved in the deep ocean reach the treacherous methane clathrates? Well I guess no one knows for certain.

    Comment by jyyh — 27 Nov 2008 @ 8:28 AM

  243. During the holidays, as one reader to another, may I suggest those coming here with questions for the first time

    – click the Start Here link at the top of the page
    – click the first link under Science in the sidebar
    – remember — it’s rare someone asks a question utterly new.

    You can look most of these things up.

    Use the Search box at the top of the page, limiting it to ‘realclimate’ search for extra creditable information.

    Comment by Hank Roberts — 27 Nov 2008 @ 9:07 AM

  244. Rob (241), I wondered the same thing, but Gavin did the math once in a response somewhere…It doesn’t come to much at all in the big picture.

    Comment by Arch Stanton — 27 Nov 2008 @ 12:31 PM

  245. So, if la nina truly decreases the observed temperatures, does the heat dissolved in the deep ocean reach the treacherous methane clathrates? Well I guess no one knows for certain.

    I’m not sure exactly what your question is, but La Nina only decreases the temperatures observed at the surface . Heat content measurements show it has almost no effect on total ocean heat content.
    The treacherous methane clathrates are mostly far from the Indo-Pacific warm pool, which is where the heat is stored during a La Nina. For methane clathrates, I believe the primary concern is the rapid warming of the Arctic Ocean (thus all the concern about the unexpected shrinkage of sea-ice cover in the summers of 2005 and 2007 (2008 reached a sea-ice coverage minimum below 2005 but above 2007)).

    Comment by llewelly — 27 Nov 2008 @ 7:14 PM

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