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Unforced variations 2

Filed under: — gavin @ 1 January 2010

Continuation of the open thread. Please use these threads to bring up things that are creating ‘buzz’ rather than having news items get buried in comment threads on more specific topics. We’ll promote the best responses to the head post.

Knorr (2009): Case in point, Knorr (GRL, 2009) is a study about how much of the human emissions are staying the atmosphere (around 40%) and whether that is detectably changing over time. It does not undermine the fact that CO2 is rising. The confusion in the denialosphere is based on a misunderstanding between ‘airborne fraction of CO2 emissions’ (not changing very much) and ‘CO2 fraction in the air’ (changing very rapidly), led in no small part by a misleading headline (subsequently fixed) on the ScienceDaily news item Update: MT/AH point out the headline came from an AGU press release (Sigh…). SkepticalScience has a good discussion of the details including some other recent work by Le Quéré and colleagues.

Update: Some comments on the John Coleman/KUSI/Joe D’Aleo/E. M. Smith accusations about the temperature records. Their claim is apparently that coastal station absolute temperatures are being used to estimate the current absolute temperatures in mountain regions and that the anomalies there are warm because the coast is warmer than the mountain. This is simply wrong. What is actually done is that temperature anomalies are calculated locally from local baselines, and these anomalies can be interpolated over quite large distances. This is perfectly fine and checkable by looking at the pairwise correlations at the monthly stations between different stations (London-Paris or New York-Cleveland or LA-San Francisco). The second thread in their ‘accusation’ is that the agencies are deleting records, but this just underscores their lack of understanding of where the GHCN data set actually comes from. This is thoroughly discussed in Peterson and Vose (1997) which indicates where the data came from and which data streams give real time updates. The principle one is the CLIMAT updates of monthly mean temperature via the WMO network of reports. These are distributed by the Nat. Met. Services who have decided which stations they choose to produce monthly mean data for (and how it is calculated) and is absolutely nothing to do with NCDC or NASA.

Further Update: NCDC has a good description of their procedures now available, and Zeke Hausfather has a very good explanation of the real issues on the Yale Forum.


1,394 Responses to “Unforced variations 2”

  1. 401
    Don Shor says:

    Matthew: “can you think of any other environmental catastrophe (in particular plant or animal extinction) that has happened, or is happening, as a result of global warming and that cannot be attributed to direct human intervention?”

    Tom Knudson has written extensively about current impacts of climate change on the Sierra Nevada mountains.
    Most of his work is in the Sacramento Bee: http://www.sacbee.com/static/weblogs/sierra_summit/
    Here is a link to his blog, sorted specifically for climate change posts: http://www.savingthesierra.org/taxonomy/term/49

    I realize that these are not scientific articles. Consider them a starting point.

  2. 402
    RB says:

    I should correct myself. The standard control structure definition for an amplifying stage that incorporates feedback is as follows:

    Output, Y= G*(X-H*Y), where X is the input, Y is the output, H is the feedback gain, G is the forward gain. This then results in
    Y= (G*X)/(1+G*H)

    If -1 < G*H < 0, there is amplification without runaway instability. But you start to see a lot of overshoots and undershoots i.e. a ringing response. But at the frequency (timescale) of interest, if G*H=-1, you have runaway instability.

  3. 403

    Some counterweight for all deniers so happily blogging, posting and twittering about present winter weather in some places: GISS update:
    November 2009 was the warmest November ever, worldwide: http://bit.ly/WarmestNov. Extremely warm (> 4 C over normal) in Arctic, mid-Canada and SE Australia.

  4. 404
    Doug Bostrom says:

    Matthew L.:

    “I am very much a product of the current state of the internet on this subject. It is impossible for me to tell whether research is s__t or truth, old or new, current or superseded. This is a great place for guidance. Much of what I say is playing ‘devil’s advocate’. I am aware that I may be completely wrong, but I, and people like me, need to be convinced.”

    Did you notice the trend of your concessions? There’s a signal there, and if you follow my rudely stated suggestion about verifying your various claims I think you’ll find that signal sufficiently robust to help with easing your doubts, if not entirely erasing them.

    We’ve collected a plethora of observations of features of the earth’s regolith, soils, oceans, biota, cryosphere and atmosphere indicating vector changes in thermal or chemical regimes.

    Certainly we can look at observed changes in single environments and hypothesize individual explanations for each. But when we integrate the results of so many diverse fields of inquiry and see that all of these features have a common direction as well as a common potential driving force the choices we have for reasonable hypotheses diminish. Ultimately we’re left with very few choices indeed. One of those– adding “greenhouse gases” including C02 to the atmosphere– comports well with our observations.

    Have I said anything controversial? I don’t think so.

  5. 405
    Completely Fed Up says:

    “I should correct myself. The standard control structure definition for an amplifying stage that incorporates feedback is as follows:”

    This isn’t op-amp theory.

  6. 406
    Completely Fed Up says:

    “Tom Knudson has written extensively about current impacts of climate change on the Sierra Nevada mountains.”

    Sorry, I’m losing it here.

    How many polar bears live in the Sierra Nevada mountains?

  7. 407
    Completely Fed Up says:

    “I don’t think that really is my motivation. It is more that experience has taught me to be sceptical of extreme views ”

    But that itself is an extreme view.

    Yet you’ve shown no skepticism in applying it.

    Try this on. Which is more likely:

    This is a world-girdling multinational conspiracy to $ONE OF MILLIONS OF IDEAS THAT ARE BAD, M’KAY$ and all the evidence is faked.

    or

    The IPCC have it right.

    Where is your skepticism on that?

  8. 408
    Completely Fed Up says:

    Arthur:
    “There is a heap of confusion on the feedback issue,… get significant things wrong – Lockwood seems to have a differing definition of forcing (measuring at the surface,”

    Uh, feedback as in “is this a positive or negative feedback” has naff all to do with that differing definition of forcing.

    “I think the best explanation is to be had by looking at the precise mathematical definition in terms of partial derivatives of various terms”

    Nope, it’s far simpler to think of it in mathematical terms:

    Positive feedback:

    X + 1/4X + 1/16X + … sum to infinite terms 1/4n where n tends to infinity.

    Plus.

    Negative feedback:

    X – 1/4X – 1/16X – … sum to infinite terms -1/4n where n tends to infinity.

    Minus.

  9. 409
    Completely Fed Up says:

    Matthew “Apart from the Polar Bears and (possibly) coral bleaching, can you think of any other environmental catastrophe … as a result of global warming and that cannot be attributed to direct human intervention?

    I am genuinely interested to know as I have failed to find any yet.”

    I’m getting flashbacks to Holy Grail and “what have the Romans ever done for us”.

    Sheesh. Did he really say “OK, you’ve given me some. But do you have any *others*???”

  10. 410
    Matthew says:

    388, John P. Reisman: It’s to easy to just say the polar bear population is increasing so AGW is wrong (a classic strawman and non sequitur).

    Yes, that happens.

    398, SecularAnimist: China is moving more aggressively to reduce fossil fuel use and build up a wind and solar energy infrastructure than is the USA, and even has higher fuel economy standards for vehicles than does the USA. Not to mention that China is already on track to become the world’s largest exporter of wind and solar technology — all technologies that were invented in the USA.

    China is increasing energy production in all technologies: coal, oil, and gas; wind, solar, and biofuels; multiple designs of nuclear. They are not “moving aggressively to reduce fossil fuel use.” As a matter of policy, I’d prefer for the US to subsidize manufacture of solar and wind devices (as China does, and some states do), instead of subsidizing their purchase, which leads to importation from China (not that I have a beef against China, but we do have a large trade deficit which I think is disadvantageous.) The US has a more restrictive regulatory environment, so it is hard to increase manufacture of anything as rapidly as China is increasing manufacture of PV cells. The US is however expanding manufacture, so we aren’t a total loss. In the US, energy from non-hydro renewable sources is increasing faster than energy consumption generally (even as gas supplants coal), something that is not yet happening in China.

  11. 411
    Don Shor says:

    Completely Fed Up:
    “Tom Knudson has written extensively about current impacts of climate change on the Sierra Nevada mountains.”
    Sorry, I’m losing it here.
    How many polar bears live in the Sierra Nevada mountains?

    None.
    I was giving Matthew some examples of current problems caused by climate change. Just because I was talking about polar bears before, doesn’t mean that all of my replies are about polar bears.

  12. 412
    Witgren says:

    Some have commented on the need for scientists to better educate the public. I thought perhaps this might of some interest to some of you: http://www.cred.columbia.edu/guide/

    It is a link to “The Psychology of Climate Change Communication”. Printed it comes to around 50 pages, or so I’ve been told. Someone recommended it to me the other day and I haven’t had time to do more than skim a few pages, but it looks interesting.

  13. 413
    Jim Eager says:

    Matthew L @400: It is more that experience has taught me to be sceptical of extreme views and extreme predictions that diverge from previous experience so radically

    Matthew, since there is currently more CO2 in the atmosphere than there has been in at least the last 3 million years and perhaps the last 20 million [Tripati, et al, Science 4 December 2009 http://www.sciencemag.org/cgi/content/abstract/1178296 ] the entire human genus has had zero experience with the kind of climate and physical conditions that will ultimately produce. Neither have any of the plant species that we have domesticated for our agriculture.

    Moreover, since there is also around 329 Gt more carbon in the active carbon cycle than there has been in at least that long, levels of atmospheric CO2 will remain elevated for not hundreds but thousands of years unless we can devise ways to remove it as fast as we put it there.

    Is it wise to discount the possibility that cloud feedback might be negative? Has anybody run climate models scenarios that assume just that?
    My fear is that this is not done because it might show that the range of outcomes for a doubling of CO2 might be more like 0 – 6 kelvin rather than 2 – 6 kelvin.

    As has already been pointed out to you, that experiment has already been run, many times, no computer models necessary. Earth’s paleohistory shows that the chance of a doubling of CO2 producing a 0-2K increase in temperature is not just slim, but zero.

  14. 414
    Jinchi says:

    Matthew L : My fear is that this is not done because it might show that the range of outcomes for a doubling of CO2 might be more like 0 – 6 kelvin rather than 2 – 6 kelvin.

    In other words, you believe that climate scientists are deliberately putting their fingers on the scales to get a preferred result. In other words, engaging in scientific fraud.

    That’s a pretty common opinion on the skeptic side of the debate (it’s pretty much the whole of the “Climategate” nonsense) and I’ve always considered an absurd one. First of all, scientists want to be right in the long run, they don’t want to be remembered in the same breath with Cardinal Bellarmine. Secondly, deliberately fudging the numbers like that would require them to tweak the results of any dependant studies so that they didn’t come into conflict. It wouldn’t take too many iterations before actual research ground to a halt and some frustrated grad student brought the whole charade tumbling down simply so he could finish his thesis.

  15. 415
    RB says:

    #405 “This isn’t op-amp theory.”

    Specifically, if forward gain in the above notation is +1 and feedback gain is (-1/2), you get the specific example you cite, i.e.,
    Y= 1*X/(1-1/2)

    which is your summation 1+1/2+1/4+1/8+… = 2 (or maybe it was somebody else’s example.

    (Just as in your example, initially 1/2 the signal is fed back, then 1/2 of this 1/2 is fed back) etc.
    The notation I described is general – therefore, I believe climate positive feedback is not different in usage from the widely used definitions.

  16. 416
    Completely Fed Up says:

    OK, RB.

    If that’s what it works out to.

    But you see my other point: it’s far easier to show with that summed series.

    If you could use MathML or Tex to draw your mathematical equation it would have been easier to see, but that just proves the point above, doesn’t it.

  17. 417
    Hank Roberts says:

    > as a result of global warming
    Bzzzzt!

    Global warming is a _result_ of increasing CO2.
    So is ocean pH change.

    Both of those have further consequences.

    Increasing CO2 is a _result_ of burning fossil fuels in excess of what natural biogeochemical cycling can handle

  18. 418
    RB says:

    BTW, just because I say feedback gain is (-1/2) don’t point to the + or – sign as representing positive/negative feedback. In my case a feedback gain of (-1/2) represents positive feedback because implicit in the expression
    Y= G*(X-H*Y) is that feedback gain H is a negative feedback that subtracts H*Y from the input. Therefore a negative number for H effectively represents positive feedback. The Barkhausen criterion applies for stability i.e. no blowing-up instability.

  19. 419
    RB says:

    More generally, the Nyquist stability criterion.
    http://en.wikipedia.org/wiki/Nyquist_stability_criterion

  20. 420
    David B. Benson says:

    RB (415) wrote “therefore, I believe climate positive feedback is not different in usage from the widely used definitions.” You are completely correct. Jim Hansen, in one of his earlier papers, started from the general definition.

  21. 421
    Ray Ladbury says:

    Matthew L. says, “My fear is that this is not done because it might show that the range of outcomes for a doubling of CO2 might be more like 0 – 6 kelvin rather than 2 – 6 kelvin.”

    OK, Matthew, it’s your turn to teach me something. Why in bloody hell would a climate scientst not want to be the one to make this crisis go away? Hell, said scientist would be famous! They’d be on Oprah! And why in bloody hell would a scientist not want to have the uncertainty right on a quantity as important as CO2 sensitivity.

    Matthew, it may shock you to learn this, but if all of a sudden, a new model came along and showed CO2 sensitivity was negligible or we had evidence that showed the same thing, all the climate scientists would heave a sigh of relief, sleep better than they have in years and GO TO WORK THE NEXT DAY AT THE SAME CLIMATE SCIENCE JOB!!! That’s right, Matthew, nobody’s job depends on the outcome to this issue! In science, you don’t get fired for being wrong as long as you did the science the right way and considered the evidence. Wrong is correctable.

    The surest path to fame and glory for a young turk scientist would be to overturn the crisis of climate change. And as to the rest of us scientists who have looked at the evidence and found it compelling, it is strongly in our interest for this crisis to go away. It will impact our funding and our research. So this idea that climate scientists aren’t overturning every rock looking for evidence that the current model of Earth’s climate isn’t just WRONG, it’s SO BAD IT’S NOT EVEN WRONG!

    Really, Matthew, I’m curious what you think motivates climate scientists.

  22. 422
    Jiminmpls says:

    #385 Don

    Take a look at the detailed table (unfortunately, only available from 2005 that I could find):
    http://pbsg.npolar.no/en/status/status-table.html

    THINK real hard, Don. Has anything happened since 2005 that has had an impact on polar bear populations? Is there reason for greater concern about polar bear populations now than there was in 2005?

  23. 423
    Doug Bostrom says:

    “My fear is that this is not done because it might show that the range of outcomes for a doubling of CO2 might be more like 0 – 6 kelvin rather than 2 – 6 kelvin.”

    Oh, brother, and here I thought we had some kind of reasonable dialog going on and whoops, down the CT rabbit hole we plunge.

    All done here for me, Matthew L. Cheerio.

  24. 424
    Hank Roberts says:

    David Appel has moved his blog to a new location.

    Good article here:

    http://trueslant.com/davidappell/2010/01/04/why-believe-in-manmade-climate-change/

  25. 425
  26. 426
    Matthew L. says:

    #404 – Doug and #409 – CFU
    Global warming induced disasters:
    Polar bears and coral bleaching. is a whole 2 “disasters”, although the bears is a predicted disaster rather than a current one, and much of the bleached coral is recovering. Still waiting to here about any others.

    I am talking about catastrophes here and now, not change. The “Vector changes” in the earths “regolith, soils, oceans, biota” are just changes, I am talking imminent disaster / extinction / desertification.

    Directly Man Made Disasters
    Amazon rainforest Destruction
    Congo rainforest Destruction
    Madagascan temperate forest destruction
    Indian jungle habitat destruction
    Malaysian rainforest destruction
    Indonesian rainforest destruction
    African and asian desertification
    Illegal hunting and poaching
    Over-fishing
    etc…

    and the many, many, consequent critically endangered species (Ignoring the merely vulnerable or endangered species) in primates alone we have

    Western Lowland Gorilla
    Cross River Gorilla
    Mountain Gorilla
    Sumatran Orangutan
    Eastern Black Crested Gibbon
    Pagai Island Macaque
    Celebes Crested Macaque
    Tonkin Snub-nosed Monkey
    Delacour’s Langur
    White-headed Langur
    Yellow-tailed Woolly Monkey
    Northern Muriqui
    Yellow-breasted Capuchin
    Superagui Lion Tamarin
    Blue-eyed Black Lemur
    Greater Bamboo Lemur
    Silky Sifaka
    Miss Waldron’s Red Colobus
    Golden-headed Langur
    Grey-shanked Douc
    Hainan Black-crested Gibbon
    Brown-headed Spider Monkey
    Kipunji

    plus
    23 species of bat
    19 large carnivores (big cats, foxes, wolves)
    6 “odd toed ungulates” (all four species of rhino, two horses)
    17 “even toed ungulates” (deer, camel, gazelle etc)
    13 species of shrew
    169 species of bird
    41 species of lizard
    16 species of snake
    6 species of crocodilians
    30 species of turtle and tortoise
    ~500 species of amphibian
    ~500 species of fish
    not to mention the plant life.

    In total there are 1,665 CRITICALLY endangered species and 2,488 merely endangered species. The vast majority of these are threatened by man’s deliberate actions in destroying them directly or through destruction of their habitats.

    Puts the poor old Polar Bear in context does it not?

    Global warming, if and when it occurs, will take decades to become apparent. We have time to adjust to and mitigate its effects. Should we build a solar generation facilities or use the money to provide alternative land for Brazillian peasant farmers who would otherwise burn down the forest? or legislate to ban unsustainable hardwood imorts? Or educate fisherman in sustainable fisheries management?

    If we opt to do the former we are in grave danger of leaving ourselves with a less warm world of deserts and extinct animals.

  27. 427
    Timothy Chase says:

    Completely Fed Up wrote in 408:

    … Positive feedback:

    X + 1/4X + 1/16X + … sum to infinite terms 1/4n where n tends to infinity.

    Plus.

    Negative feedback:

    X – 1/4X – 1/16X – … sum to infinite terms -1/4n where n tends to infinity.

    Minus.

    Don’t mean to be argumentative or anything, but if X is the forcing and (-1/4)x the initial feedback to the forcing, wouldn’t the next term — representing the feedback to the initial feedback — be positive in sign? For example, the initial rise in temperature due to the forcing results in an initial cooling feedback, wouldn’t the initial feedback to the initial feedback (second order feedback?) be a warming feedback?

    Not that climate models work by means of calculating feedbacks — they work based upon physical principles.

    For example with positive feedback, increasing solar absorption raises the temperature resulting in more evaporation (as the partial pressure of water is a function of temperature) where the resulting water vapor absorbs infrared based upon its spectral emissivity, the spectra and intensity of the incident light, and then emits infrared based upon its temperature, raising the temperature, resulting in further evaporation and so on.

    Likewise, with negative feedback, increased evaporation may lead to greater low level clouds, increasing the albedo of the atmosphere, reducing the amount of solar radiation that reaches and would otherwise be absorbed by the darker surface, resulting in a cooling effect, but the cooling effect will reduce the amount of evaporation that takes place, reducing the formation of clouds, therefore reducing the albedo, increasing the absorption of solar radiation and therefore raising the temperature.

    However, after climate models have done their calculations, for the purpose of our understanding it makes sense to speak of forcing and feedbacks and climate sensitivities — as to a first approximation the net feedback is proportional to the forcing and climate sensitivity remains constant.

    Likewise, it really doesn’t make that much sense to break things out into positive and negative feedback or into a series — in as much as the feedbacks are taking place simultaneously. But if one does break things out into a series for conceptual reasons then a negative feedback would result in an alternating series. And pointing this out I believe might help in understanding what negative feedback is and therefore what feedback is.

    Incidentally, what we actually seem to be seeing with cloud formation under an enhanced greenhouse effect is stronger moist air convection leading to a reduction in low level clouds and an increase in high level clouds — such that shifting the balance cloud-based albedo and cloud-based greenhouse effect from the cooling former to the warming latter. So clouds would seem to be a positive feedback.

    If the temperature of the clouds is nearly the same as the ground as the result of being closer to the ground, they will tend to radiate heat to the upper layers of the atmosphere, but if they are cooler than the ground as the result of being at a higher altitude then they will tend to absorb higher temperature radiation rather than emit it to space. This will result in the trapping heat — keeping more thermal energy in the climate system — and reduce the net rate at which the surface is able to radiate thermal energy to higher layers of the atmosphere and ultimately to space.

    Somewhat tentative, but please see:

    Cloud feedback could accelerate global warming
    Jul 23, 2009
    http://physicsworld.com/cws/article/news/39908

    Provisional evidence for positive cloud feedback
    July 28, 2009
    http://thingsbreak.wordpress.com/2009/07/28/provisional-evidence-for-positive-cloud-feedback/

    Clement et al. (2009 July 24) Observational and Model Evidence for Positive Low-level Cloud Feedback. Science 325(5939):460-464
    *
    Oh, and this might help sum:

    Geometric Series: Sum
    http://en.wikipedia.org/wiki/Geometric_series#Sum

  28. 428
    calyptorhynchus says:

    #393 “Apart from the Polar Bears and (possibly) coral bleaching, can you think of any other environmental catastrophe (in particular plant or animal extinction) that has happened, or is happening, as a result of global warming and that cannot be attributed to direct human intervention?

    I am genuinely interested to know as I have failed to find any yet.

    I could give you several thousand instances where plant and animal species populations are declining due to habitat destruction, hunting or over exploitation.”

    As a biologist you will know that most changes in the natural world are the result of complex causation, not just one or two causes.

    However, as AGW is such a biggie then it can be expected to amplify the other causes you identify, such as “to habitat destruction, hunting or over exploitation” in a major way.

    From my own neck of the woods I would nominate the decline of southern Australian woodlands and their animal and bird species. This is surely due to habitat destruction, but the way that the periodic droughts in southern Australia now seem to be joining up has amplified habitat destruction.

    Mac Nally, R, Bennett, A. F., Thomson, J. R,
    Radford, J. Q., Unmack, G., Horrocks, G., Vesk, P. A.
    (2009) Collapse of an avifauna: climate change appears
    to exacerbate habitat loss and degradation.
    Diversity & Distributions, Vol. 15, No 4, pp. 720-730.

  29. 429
    Jim Eager says:

    Re Matthew L. @393 sea level is rising at a rate of around 2mm a year

    Another Bzzzt: The rate of sea level is rise increased to 3.0 to 3.2 mm / year in the early 1990s.

    And @426: Global warming, if and when it occurs, will take decades to become apparent.

    And a really big Bzzzt: Dude, it is already quite clear to anyone who bothers to look at the evidence that global warming is already occurring, including Christy, Lindzen, Michaels, Spencer, and even Lomborg.

    We have time to adjust to and mitigate its effects.

    Are you sure? Are you willing to bet everything on it? Because that is exactly what you are advocating.

    And you don’t even have the basic facts right.

  30. 430
    G. Karst says:

    December (month end averages) NSIDC (sea ice extent)

    30 yrs ago
    1980 Southern Hemisphere = 11.1 million sq km
    1980 Northern Hemisphere = 13.7 million sq km
    Total = 24.8 million sq km

    Recorded Arctic min yr.
    2007 Southern Hemisphere = 12.7 million sq km
    2007 Northern Hemisphere = 12.4 million sq km
    Total = 25.1 million sq km

    Last yr.
    2008 Southern Hemisphere = 12.2 million sq km
    2008 Northern Hemisphere = 12.5 million sq km
    Total = 24.7 million sq km

    This yr.
    2009 Southern Hemisphere = 11.4 million sq km
    2009 Northern Hemisphere = 12.5 million sq km
    Total = 23.9 million sq km

    1979-2000 Southern Hemisphere Dec. mean = 11.1 million sq km
    1979-2000 Northern Hemisphere Dec. mean = 13.4 million sq km
    Total mean = 24.5 million sq km
    GK

  31. 431
    jyyh says:

    I have to note that NSIDC has started giving forecasts in their monthly bulletin: “Figure 5. The map of sea level pressure anomalies (in millibars) for December 2010″…

  32. 432
    Don Shor says:

    Jiminmpls
    “THINK real hard, Don. Has anything happened since 2005 that has had an impact on polar bear populations?”
    That HAS had an impact? Apparently not, since the population estimate is the same in 2009. That MIGHT have an impact at some future time? Certainly.

    “Is there reason for greater concern about polar bear populations now than there was in 2005?”
    Sure. But I repeat that much of the problem appears to have been harvest management, and that the polar bear is not the best poster child for AGW. There are a lot of better examples posted by Matthew L in #426.

    By the way, you might want to stop being offensive. Ok?

  33. 433
    Didactylos says:

    Global warming, if and when it occurs, will take decades to become apparent.

    This should cause you grave concern. Our actions of the past will have an impact in decades to come. If we continue to do nothing except emit carbon, then not only will we be reaping the reward of our past emissions, but we will be storing up yet more warming “in the pipeline” for our descendants.

    As for the fear-mongers on both sides: be realistic about what we expect to see in the future. Here is a good graphical summary: http://maps.grida.no/go/graphic/projected-impact-of-climate-change

    Remember that Copenhagen was trying to peak at 2 degrees. Knowing humanity, that’s optimistic.

  34. 434
    Doug Bostrom says:

    Don Shor says: 5 January 2010 at 10:27 PM

    “Sure. But I repeat that much of the problem appears to have been harvest management, and that the polar bear is not the best poster child for AGW.”

    Polar bears are after all just one signal of many, true enough.

    It’s helpful to note that the polar bear experts group is composed not only of biologists with a bear bent, but “managers” as well. They’ve got the “harvest” thing pretty well in hand, as evidenced by the rebound since we finally noticed that we’d killed too many of ‘em. Meanwhile, they all seem to agree that the present looming issue for these animals is loss of habitat due to climate change effects.

    I have to laugh somewhat ruefully at that term, “harvest”. Like ears of corn or some other vegetable matter, except of course that ears of corn don’t have the distressing tendency to thrash around bleeding and howling after having been shot, and of course ears of corn don’t have dependents waiting for dinner. Call me an old softy, but maudlin attachments to brutal, anachronistic rituals make me squirm a bit.

    Matthew L., as I mentioned already your swerve into conspiracy theory ended any desire I had for conversation with you. Wallow in your false worries about opportunity costs freely, have the last word on me.

  35. 435
    Tim Jones says:

    Re #448
    Thanks much for the links, Gavin. This helps a lot.

    Re #351
    Thanks too Rattus. But I’m finding Cheetham’s “Interactive Climate Data Graphing” doesn’t allow adjusted data to be plotted for Texas. The pages’ architecture is pathetic.

    Much better temperature data plotting is available from GISS.

    GISS Surface Temperature Analysis
    http://data.giss.nasa.gov/gistemp/station_data/

    Here is Austin’s “raw GHCN + USHCN corrections” data plotted:
    http://data.giss.nasa.gov/work/gistemp/STATIONS//tmp.425722540000.0.1/station.gif
    And:
    here is Austin’s “after homogeneity adjustment” data plotted:
    http://data.giss.nasa.gov/work/gistemp/STATIONS//tmp.425722540000.2.1/station.gif

    A warming trend becomes clear. (The graphs are conveniently geographically named.)

    Some of the anti-science propagandists are unglued because some of the stations they looked at were adjusted for things that didn’t seem appropriate to them. Thus they preferred to use only raw data to evaluate trends. Mostly they could not find a warming trend in the last 30 years
    in the USA. (Neither could I.)

    Since this seems to be the crux regarding the application of scientific method to raw temperature data plots, one of the things GISS scientists could focus on is a clear explanation of exactly why the particular data was/is adjusted for any particular site.

    All the bad guys have to do is sow the seeds of doubt and confusion. Scientists have to ensure the BGs can’t do that with any sense of legitimacy.

    It’s useful to peruse the comments sections following GW articles for intelligence gathering purposes as well. One sees the anti-science PR boys targets du jour.

    In this regard, but as devil’s advocate I would like to know exactly why/how Austin’s data was adjusted to make the rising temperature trend more apparent – and not just a trick, myself. An answer to this would arm me enough in the next go-round in the news forum wars to put the truth of it on the table.

    For what it’s worth, someone did a survey of who said what for twelve hours of back and forth on the Washington Post’s article comments pages. Some 50% were dismissed by appellation as “trollspam.” Those of us actually trying to add to understanding were acknowledged kindly for our depth of knowledge. I was amazed. It seemed to be worth the effort to reach people with a truthful view of AGW.

  36. 436
    Edward Greisch says:

    I have heard that the whole midwest becomes a desert, and the opposite. That the monsoon misses India and China completely in X years. Etc. I know that “the rain moved” has caused many previous civilizations to collapse.
    Do you know anything about where the rain is going to move that the rest of us don’t?

  37. 437
    Tim McDermott says:

    Matthew L. says:
    5 January 2010 at 7:54 PM

    I am talking about catastrophes here and now, not change. The “Vector changes” in the earths “regolith, soils, oceans, biota” are just changes, I am talking imminent disaster / extinction / desertification.

    Try this from Nature

    Here we show that a recent mass extinction associated with pathogen outbreaks is tied to global warming. Seventeen years ago, in the mountains of Costa Rica, the Monteverde harlequin frog (Atelopus sp.) vanished along with the golden toad (Bufo periglenes). An estimated 67% of the 110 or so species of Atelopus, which are endemic to the American tropics, have met the same fate, and a pathogenic chytrid fungus (Batrachochytrium dendrobatidis) is implicated. Analysing the timing of losses in relation to changes in sea surface and air temperatures, we conclude with ‘very high confidence’ (> 99%, following the Intergovernmental Panel on Climate Change, IPCC) that large-scale warming is a key factor in the disappearances. We propose that temperatures at many highland localities are shifting towards the growth optimum of Batrachochytrium, thus encouraging outbreaks. With climate change promoting infectious disease and eroding biodiversity, the urgency of reducing greenhouse-gas concentrations is now undeniable.

    Is 70-80 species extinct enough?

  38. 438
    Tim Jones says:

    #393 “Apart from the Polar Bears and (possibly) coral bleaching, can you think of any other environmental catastrophe (in particular plant or animal extinction) that has happened, or is happening, as a result of global warming and that cannot be attributed to direct human intervention?

    Try Adelie Penguins.

    “Adelie Penguins Extinct in a Decade in Some Areas?”
    http://news.nationalgeographic.com/news/2007/12/071228-penguins-extinct.html
    Anne Casselman
    for National Geographic News
    December 28, 2007
    “Adélie penguins in Antarctica are in the midst of a major upheaval as climate change causes their icy habitat to warm up, experts say.”
    “Some populations of the birds are thriving, but most are declining rapidly.”
    […]

  39. 439
    Edward Greisch says:

    http://www.greenprophet.com/2010/01/05/15665/arab-world-water-protection/
    So far, climate change has caused a 30 per cent reduction in the Kingdom [of Jordan]’s surface water resources….
    Here is a real problem in real time for RC to talk about. How can they deny this?

  40. 440
    Martin Vermeer says:

    Matthew L. #393,

    sea level is rising at a rate of around 2mm a year and has done at least as fast, if not faster, since approximately the end of the last ice age.

    You remember wrong:

    http://en.wikipedia.org/wiki/File:Post-Glacial_Sea_Level.png

    and references therein.

    Sea level has been rising around 1.5 mm/yr over the tide gauge period, accelerating to 3.4 mm/yr over the satellite altimetric period. References left as an exercise for the reader ;-)

  41. 441
    Completely Fed Up says:

    Edward asks:
    “Here is a real problem in real time for RC to talk about. How can they deny this?”

    They’ll say “prove it’s because of CO2!”.

  42. 442
    Completely Fed Up says:

    Ah good old G Karst.

    Continuing his ever present quest to confirm AGW whilst mistakenly beleiving that he’s proving it wrong.

    It’s like spring daffodils rising.

    It means midwinter on one of the two poles has arrived.

    G Karst, where’s the sea ice volume metrics? And your figures prove that we’ve lost 800,000km2 of sea ice in the southern hemisphere in one year. At that rate, we’ve only got ~14 years of southern polar ice left.

  43. 443
    Completely Fed Up says:

    “Don’t mean to be argumentative or anything, but if X is the forcing and (-1/4)x the initial feedback to the forcing, wouldn’t the next term — representing the feedback to the initial feedback — be positive in sign?”

    Maybe.

  44. 444
    Matthew L. says:

    #429 – Jim
    http://www.climate4you.com/SeaTemperatures.htm#Global sea level
    From the recent satelite record since the end of 1992 global mean sea level has risen 15mm (using the trend line), just under 1mm a year. No Bzzt there then.

    By “global warming” I am using shorthand. I should have said catastrophic, irreversible, anthroprogenic global warming that is clearly visible above the noise of natural variability. You might think that is the case, my reading of the data is that the jury is still definately out.

    Sure the globe is warming, the temperature record shows that. I know most climate scientists are of the opinion that Mann and co settled the argument years ago, but his methodolgy is controversial and the proxy data he is working with is rather thin on the ground at best.

    As stated earlier, I am probably just a mirror put up to the internet, so use me as a reflection on how the current debate appears to the reasonably intelligent (albeit sceptical by inclination) observer.

    The “denialist meme” de jour is that the positive feedbacks in the models are too high, and in particular that clouds and ocean currents are not sufficiently well modelled. Ray here has said there are 10 lines of enquiry all supporting feedbacks at the levels currently used. I have tried looking but failed to find any paper detailing these. A link would be useful.

    On the accusation that I am shouting “conspiracy” I don’t think I am. I think there is an element of “circling the wagons” and groupthink going on, but I am sure there is no deliberate attempt to falsify any science. There appears (again to the casual observer) to be a tendancy to put more effort into finding ways of proving your chosen hypothesis and defending it rather than deliberately setting out to try and find ways why it might be wrong. This is a natural human reaction when challenged. The best scientists are the ones who try hard to disprove their own hypothesis. If they are not willing to do that themselves they should let others do it for them – with good grace rather than by shouting “denier” all the time.

    I am no scientist and I am sorry if anybody here thinks I am personally denigrating their work. That is absolutely not my intention. What I am trying to do here is using myself as a channel into the RC debate for some of the main sceptical arguments currently out there on the interweb. Sometimes the debate here can seem a little sterile with everybody agreeing with each other and having fun jumping on sceptics.

    Although not a scientist myself, I am from a scientific background and from my ealiest days been fascinated by science and the environment. I am by no means “anti-science”, Richard Dawkins is a particular hero of mine.

  45. 445
    Ray Ladbury says:

    Meanwhile Gary Karst has a news bulletin: December in the Northern Hemisphere is still cold.

    Golly, thanks, Gary!

  46. 446
    Ray Ladbury says:

    Matthew L. @426, So Matthew, I take it that you are only interested in events that will affect YOU directly and are content to let future generations go hang. Correct?

  47. 447
    Bill says:

    Its curious that we still seem to have such an uphill battle getting across the interpretation of scientific data to the public at large. A lot of people switch off when confronted with statistical probability of something happening, or a temperature ‘anomaly’, or repeated aberrant long term ‘forecasts’ by supposedly expert met experts.
    On the other hand, if you ‘eye-ball’ long-term absolute temperature data ( such as Armagh in Ireland, Hadley CET in England which are apparently well documented and stable data collections), you can see that the temperature record in the last 10-20 years are like those in 1820-1830 and further back in 1693-1730.
    I can kind of understand why we have the communication issues we do…..

  48. 448
    Shills says:

    What do people think of the most recent Bray, Von Storch survey here:

    http://coast.gkss.de/staff/storch/pdf/CliSci2008.pdf

    Sorry if this has already being answered and if so, could you link me to its discussion? I don’t wan’t to pass it off as evidence for general consensus on AGW if it is a shoddy survey.

    Also is there a some official definition for ‘significant’ in science? As in: ‘man-made warming is significant’ The lay definition seems too vague.

  49. 449
    Jiminmpls says:

    I’m surprised no one has mentioned the mountain pine beetle as an example of catastrophic change resulting form AGW.

    And Don, I see no reason to be polite to anyone who says that “Evidence of these environmental changes, in conjunction with a re-evaluation of the polar bear subpopulations, have led PBSG to list eight of 19 subpopulations as currently decreasing, three as stable and one as increasing.” means that polar bear populations are not decreasing.

  50. 450
    jyyh says:

    the trouble with using the beetles and other such pests as evidence of GW is a bit unpractical and tricky since there have been outbreaks in the 1930s before most of the insecticides were found out. i admit the scale of that is pretty worrying.


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