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  1. Orwell lives and then some.

    Comment by gerald spezio — 9 Jul 2007 @ 8:18 AM

  2. Based on UC Irvine study of Artic warming/melting http://today.uci.edu/news/release_detail.asp?key=1621 and the lack of Antarctic warming or melting raises the possiblility that the Greenland Ice sheet, which is miles thick, is less affected by dirty show and water temperatures then was though in the past? Since a significant amount of the Artic warming is due to pollution, not temperate and tropical latitude heating, up to 94 percent according to the UCI study, then would not cleaning up the pollution do away, over time, with Artic warming and melting, therefore stabilizing the Greenland Ice sheet?

    At least this needs to be studied as it is significant to both GCMs and policy decisions.

    [Response: The effect of black carbon on snow is significant and does have a greater effect in the Arctic than elsewhere, but single factor explanations for what we are seeing are inadequate. See Hansen et al (2005) or 2007 for discussions of how that one individual forcing fits in to all the other changes. Going forward, the biggest growth in the warming factors is likely to be CO2, not black carbon, but efforts to reduce BC could certainly help. -gavin]

    Comment by Vernon — 9 Jul 2007 @ 8:19 AM

  3. Obviously, journalists would like to know more, than the research says ;-)

    Was the position of Greenland 125,000 ago the same or similar as of today? As unfortunate I see the statment “more stable than previously though”… but in any case, will the sea level rise be the most serious, we can await from future climate change? Won’t be the precipitation and weather pattern changes more important than that?

    Best,

    Comment by Alexander Ac — 9 Jul 2007 @ 8:29 AM

  4. Comment by Anonymous — 9 Jul 2007 @ 8:47 AM

  5. RE: 2 Gavin, fully understanding that more needed to be done that just the UCI study, what if the high end numbers are correct? If current warming is due to black carbon (94 percent, and I know we cannot be sure of that with out further study) what does that due to the current theory and what impact does that have on current models?

    [Response: But it doesn't explain global warming at all. Though as I said, attributions based on single factor experiments are not sufficient. For instance, other aerosols provide a cooling effect and so you could easily have CO2 and BC both providing 0.5 deg C of the effect in the Arctic, and the sulphates providing -0.5 deg C for a total of 0.5 deg C warming. Thus CO2 and BC would both provide 100% of the effect! Modelling of each of the factors will no doubt improve, but as of now, BC is a minor player, though non-negligible - but then so are tropospheric ozone, methane, N2O, sulphates, nitrates, solar, volcanics, land use change etc. - gavin]

    Comment by Vernon — 9 Jul 2007 @ 9:11 AM

  6. A little knowledge can be a dangerous thing!
    Having done some work training journalists in science I can tell you their experience and knowledge (even for “scientific/environmental” reporters) can vary wildly..

    that said, I think the naysayers will always find a way to twist anything to suit their needs…

    [Response: This wasn't an issue with the journalists nor with the naysayers, it is an issue of scientists (and their press offices) using a news peg that was guaranteed to produce confused and inaccurate stories. Journalists and editors can't be blamed for writing stories that reflect that. - gavin]

    Comment by Bryan — 9 Jul 2007 @ 9:14 AM

  7. Hello good readers of Realclimate.org. I have spent a considerable amount of effort documenting the scientific consensus on my website here:

    Logical Science: The Consensus on Climate Change: From Science to Industry & Religion

    As you can see the list is pretty extensive and it’s probably the most definitive list on the web. I have received numerous e-mails recently asking about organizations outside of the US. Obviously there are language barriers that get in my way so I’d appreciate some guidance from RC’s foreign readers. Also, if anyone thinks I’ve missed any important statements I’ve missed (especially from industry) please email me. My email is posted at the bottom of every page on http://www.logicalscience.com.

    Sorry for the hijack Gavin but I’m sure you can agree this is for a good cause!

    Comment by wacki — 9 Jul 2007 @ 9:29 AM

  8. I guess the authors conclusions are based on the idea that the odds the ice core just happened to hit on an ancient glacier or some isolated patch of ice were small enough to disregard and that their results indicate the presence of an ice sheet at least 50% the size of the current one in S. Greenland since they halved the ice sheet’s sea level contribution. Is this valid?

    How did the core drillers choose their site? How good of a picture do scientists have of Greenland’s underlying topography? Was the core purposely placed in a spot likely to hold a continuous record of ice such as a high mountain valley?

    The simultaneous ideas that S. Greenland was both covered by an all encompassing ice sheet and supported a boreal forest seem contradictory to me. Gavin seems to point this out in his quote. I do like the graphic which pictures a mountain and glacier in the background. That makes sense.

    It also reminds me of a nice story published in Wild Earth (now defunct) about the work of scientists studying the preserved insects literally pouring out in the meltwater from a disappearing glacier in Montana. Here is something recent but I’m sure a search of Dr. Lockwood’s work would bring up quite a few publications. Lockwood, J. A., J. C. Burne, L. D. DeBrey, R. A. Nunamaker and R. E. Pfadt. 1990. The preserved fauna of grasshopper glacier (Crazy Mountains, Montana): Unique insights to Acridid biology. Boletin de Sanidad Vegetal 20: 223-236. Dr. Lockwood has studied N.America’s now extinct locust species by examining the grasshoppers which flew or were blown up onto the glacier and preserved until now.

    Comment by Andrew Sipocz — 9 Jul 2007 @ 9:47 AM

  9. The question remains, how much ice remained on Greenland during the Eemian?

    Comment by Todd — 9 Jul 2007 @ 10:19 AM

  10. It is a shame that the article does not expand on the science of the Eemian itself and tell us how much additional heat the orbital configuration of the earth gained to be 1 to 2 degrees C warmer than todays interglacial which created that 6M sea level difference?

    If the northern hemisphere was warmer what would happen to the southern hemisphere and Antartica in particular, would it not be colder there ?

    Were CO2 and other GHG concentrations the same as preindustrial levels 125,000 years ago.

    How long did the Eemian last and was it warmer through the entire phase of that interglacial.

    great post once again RC.

    Comment by pete best — 9 Jul 2007 @ 10:38 AM

  11. I can’t find the reference, but I definitely remember someone describing the Eemian southern Greenland ice cap as a steep dome as they attributed its contribution to the Eemian high sea level stand. Have Gavin, Hansen, Rahmstorf ever described the southern Greenland ice cap as non-existent during the Eemian? Is this simply a case of a molecular biologist making incorrect assumptions on behalf of other scientific disciplines?

    [Response: The reference you refer to is Otto-Bliesner et al (2006): http://www.sciencemag.org/cgi/content/abstract/311/5768/1751 - gavin]

    Comment by Andrew Sipocz — 9 Jul 2007 @ 11:01 AM

  12. RE:11 AR4 indicates that ice sheet models predict complete Greenland melting with 4 times pre-industrial co2 levels sustained for centuries. Maybe someone needs to take a second look at the models.

    Comment by Sam — 9 Jul 2007 @ 11:49 AM

  13. Sam,
    Actually, 4x CO2 might well do it. That’s a lot of warming for a fairly long time.

    Comment by Ray Ladbury — 9 Jul 2007 @ 12:08 PM

  14. Pete Best:

    Were CO2 and other GHG concentrations the same as preindustrial levels 125,000 years ago.

    Although CO2 levels during most of the Eemian were indeed close to preindustrial levels of about 275 ppmv, the peak of Eemian CO2 levels, at nearly 125 kyr ago, was about 290 ppmv, significantly higher. See globalwarmingarg.com Current CO2 level is about 383 ppmv . (Which I take to mean that if CO2 levels do not come down substantially within the next few centuries, all this argumentation about the extent of GIS melting during the Eemian is argumentation about the wrong example.)

    Comment by llewelly — 9 Jul 2007 @ 12:19 PM

  15. Gavin:
    Thanks for the clarification.
    If it is a case of scientists using the press/news by manipulating their releases, then shame on them, not the press.
    Thanks

    Comment by Bryan — 9 Jul 2007 @ 12:26 PM

  16. Gavin,

    I was hoping that this would be the next topic you would cover. Thank you for granting my wish, especially as I hadn’t mentioned it.

    It sounds like rather than overturning the mainstream view, this result actually just confirms it – namely, the half-and-half between the Western Antarctic Peninsula and Greenland. One point though: I believe I ran across a statement by you that suggested that the study might indicate that Greenland is actually more unstable than it has appeared so far.

    Am I remembering correctly, and if so, what is the reason for this view?

    [Response: Because it does show definite proof that southern Greenland was deglaiciated in the relatively recent past. Previous inferences were indirect. - gavin]

    Comment by Timothy Chase — 9 Jul 2007 @ 12:28 PM

  17. Actually, if sulfates are blocking income radiation and most if not all Arctic warming can be attributed to Black Carbon, then there is nothing to indicate that the warming is due to CO2. This does not go against the physics, since CO2 can only cause warming if the radiation penatrates to the CO2 and the sulfates stop it. This means that CO2 could go to 4 times with out heating the Arctic just as current CO2 increase may not be heating the Arctic.

    Comment by Vernon — 9 Jul 2007 @ 12:29 PM

  18. RE: 14 If the Arctic warms and releases all trapped greenhouse gas, then why when the Arctic melted last and Greenland mostly or completely melted did the CO2 level not go up? Why did the CO2 in the sea not also get release?

    Comment by Vernon — 9 Jul 2007 @ 12:32 PM

  19. gavin (inline to #16) wrote:

    Because it does show definite proof that southern Greenland was deglaiciated in the relatively recent past. Previous inferences were indirect.

    Well, given IPCC recommendations, it looks like we will get our two degrees – and that is assuming we have the political will needed to put into action those recommendations. Plus the problem with carbon soot wasn’t something which we had in the recent past. So this would suggest additional warming. Moreover, I would suspect that in terms of ice dynamics, it isn’t just a question of how much the temperature rises, but how quickly – given the nature of non-linearity involved in glacier melt.

    Comment by Timothy Chase — 9 Jul 2007 @ 12:41 PM

  20. Sam:

    RE:11 AR4 indicates that ice sheet models predict complete Greenland melting with 4 times pre-industrial co2 levels sustained for centuries. Maybe someone needs to take a second look at the models.

    2x pre-industrial CO2 is about 550 ppmv. 4x is about 1100 ppmv . The highest in level in the last 400 kyr was about 310 ppmv . Older CO2 levels are uncertain, but based on this graph , the last time 550 ppmv was exceeded may have been as long ago as the middle Paleogene. As far as I know, there were no ice sheets at the present-day latitudes of Greenland during the Paleogene, but the arrangement of the continents was significantly different. I think this greatly limits how much we can learn about the effects of centuries of 2x CO2 (much less 4x CO2) from paleo-climate studies.

    Comment by llewelly — 9 Jul 2007 @ 12:46 PM

  21. Vernon, you’ve got the direction backward: incoming sunlight penetrates to the ground, the ground radiates in the infrared, and the CO2 slows down the loss of that energy back into space.

    You can tell for sure that the sulfates are not blocking all the incoming radiation, because the sky is bright during the daytime.

    Comment by Hank Roberts — 9 Jul 2007 @ 12:51 PM

  22. Vernon (#17) wrote:

    Actually, if sulfates are blocking income radiation and most if not all Arctic warming can be attributed to Black Carbon, then there is nothing to indicate that the warming is due to CO2. This does not go against the physics, since CO2 can only cause warming if the radiation penatrates to the CO2 and the sulfates stop it. This means that CO2 could go to 4 times with out heating the Arctic just as current CO2 increase may not be heating the Arctic.

    Hansen strongly recommends the reduction in black carbon. Carbon dioxide acts in the stratosphere. Aerosols are an issue principally in the thermosphere – and to counter the effects of increasing levels of carbon dioxide without attempts to curb its growth, we would have to emit a geometrically increasing amount of aerosols, particularly since they tend to be washed out by rain. Carbon dioxide isn’t. And while aerosols have masked the effects of carbon dioxide until quite recently, they aren’t doing so as effectively any more. In addition, aerosols have their own problems associated with them in terms of acid rain, their effects upon the weather, and the associated lung ailments.

    And we have a good estimate of climate sensitivity to carbon dioxide as the result of paleoclimate studies. Roughly 2.9 degrees Celsius per doubling.

    Comment by Timothy Chase — 9 Jul 2007 @ 1:01 PM

  23. “This does not go against the physics, since CO2 can only cause warming if the radiation penatrates to the CO2 and the sulfates stop it.”

    Vernon, you are a brave man ready to take all the deserved beating on this most ridiculous argument for long time!

    Comment by Petro — 9 Jul 2007 @ 1:09 PM

  24. http://tinyurl.com/329qwz

    Two New Articles Which Document The Limitations Of The Multi-Decadal Global Climate Model Predictions

    I’m not qualified to vet his arguments. Are the models as broken as he indicates?

    Comment by rick kennerly — 9 Jul 2007 @ 1:11 PM

  25. Re # 18 Two New “Articles”
    According to your source (Roger Pielke Sr. Research Group Weblog):
    “The first new information is in a poster … entitled “Inter-model Climate Sensitivity” by J.T. Kiehl and C.A. Shields. ”

    Be aware that conference posters are not peer-reviewed (even if the abstract is, which is often not the case).

    “… a second article that highlights the overselling of the 2007 IPCC WG1 Report’s statement on the multi-decadal global model predictions…is in Nature Reports Climate Change Published online: 27 June 2007 … in an article by Stephen E. Schwartz, Robert J. Charlson & Henning Rodhe entitled “Quantifying climate change – too rosy a picture?”

    I haven’t read this, but it appears to be a news article rather than a peer-reviewed research article. As with press releases, one has to read such articles with caution, even if they are written by scientists.

    Comment by Chuck Booth — 9 Jul 2007 @ 1:37 PM

  26. Sam (#12) wrote:

    RE:11 AR4 indicates that ice sheet models predict complete Greenland melting with 4 times pre-industrial co2 levels sustained for centuries. Maybe someone needs to take a second look at the models.

    Not what mention of Greenland I have found in the AR4WG1:

    The inferred warming was largest over Eurasia and northern Greenland, whereas the summit of Greenland was simulated to be 2 C to 5 C higher than present. This is consistent with ice sheet modelling suggestions that large-scale retreat of the south Greenland Ice Sheet and other arctic ice fields likely contributed a maximum of 2 to 4 m of sea level rise during the last interglacial, with most of any remainder likely coming from the Antarctic Ice Sheet.

    pg. 435, AR4WG1, Chapter 6

    The way I read this, it is entirely consistent with the analysis given in Gavin’s essay above. Perhaps you have in mind a different passage?

    Comment by Timothy Chase — 9 Jul 2007 @ 2:16 PM

  27. Gavin, the EEmian period, 125,000 years ago is interesting for more than one reason. Genetic studies of the 3 kinds of human body lice reveal that taenia corporis, the body louse of man is very closely related genetically to the chimpanzee head louse, but it attaches only to clothing and not to skin, giving rise to the theory that humans did NOT wear any clothes, even animal skins, at about that same period in history, 125,000 years ago plus or minus. Not necessarily in Greenland of course, but the temperature rise elsewhere may have been more significant causing no thought of clothing and probably further promoting,also the evolutionary loss of much body hair then already underway for millions of years. What do you think of this cognitive anthropological approach to evolutionary theory and how it may also support climate-change models?
    Vern Johnson

    Comment by Vern Johnson — 9 Jul 2007 @ 2:34 PM

  28. RE: 23 Why is this the most ridiculous argument for long time! If black carbon could be responsible for all most all warming and melting in the Arctic, then where is the CO2 based warming? It is not happening in the Antarctic.

    Has anyone considered that maybe we got it wrong. That black carbon is rasing the temps in the Arctic and that is warming the rest of the NH? I don’t really thank so but how about some proof?

    Comment by Vernon — 9 Jul 2007 @ 2:55 PM

  29. Re:Comment by Andrew Sipocz â�� 9 Jul 2007 11:01 am amd Gavin’s inline response
    referencing Otto-Bliesner et al., Science 311, pp. 1751-1753

    I see from the reference that the Dye 3 was at the edge of the icesheet in simulation A in Fig. 3 of the reference. So is it not possible that the simulation for LIG is slightly off and that the Dye-3 site was glaciated through the LIG ?

    Further this supports the theory that W. Antarctica contributed substantially to sea level rise in the LIG, although the insolation anomaly was small in the Southern Hemisphere. By contrast, CO2 forcing is not confined to the Northern Hemisphere, so naively I would think the effects this time around will be larger in Antarctica. The other question in my mind is the role of sea level rise and ocean warming in the destabilization of W. Antarctica. As shown by Barnett et al. Science v309, pp.284-287, there is significant warming in the S. Hemisphere oceans which will do no good to the ice shelves in Antarctica.

    This line of thought led me to revisit Mercer, Nature, 1978, v271 pp.321-325. I reproduce a sentence here:
    “One warning sign that a dangerous warming is beginning in Antarctica, will be a breakup of ice shelves in the Antarctic Peninsula just south of the recent January 0C isotherm; the ice shelf in the Prince Gustav Channel on the east side of the peninsula, and the Wordie Ics Shelf; the ice shelf in George VI Sound, and the ice shelf in Wilkins Sound on the west side {Fig 2).”

    I note that each of these shelves is in retreat or gone, as shown by the following:
    http://www.iitap.iastate.edu/gcp/sealevel/ross.html
    Smith et al. Antarctic Science, 19(1), pp131-142 (2007)
    http://pubs.usgs.gov/fs/fs17-02/fs017-02.html

    I should really go back and reread Weertman, Hughes, and some of the other ‘instabilists’ …

    sidd

    Comment by sidd — 9 Jul 2007 @ 2:59 PM

  30. OK, Vernon, I’ll bite. How does black carbon on the ice caps warm the entire Northern Hemisphere. And while you’re at it, maybe you can explain where the “sulfates” that block the IR come from and how they succeed in keeping the IR away from the CO2. Maybe you could tell us where the IR comes from.
    Vernon, this brings up a question. With so little knowledge of the theory behind anthropogenic climate change, how do you even know what you are opposing? You seem to think there is some region where the CO2 resides, and if you can just keep the IR radiation away from it, you won’t get any warming. Please, Vernon, I am sincere when a beg of you to do some reading on this site. Ask some question about the theory and why scientists who study this subject are convinced that 1)the climate is changing, and 2) we are behind those changes. I strongly recommend the essays “A Saturated Gassy Argument” and “What Angstrom didn’t know” a couple of essays down. Vernon, you owe it to yourself to be well informed that you can at least state the argument of your opponent correctly. I don’t care if you stay a skeptic, but at least learn what you are skeptical of.

    Comment by ray ladbury — 9 Jul 2007 @ 4:24 PM

  31. Re #18: Vernon said: “If the Arctic warms and releases all trapped greenhouse gas, then why when the Arctic melted last and Greenland mostly or completely melted did the CO2 level not go up”?

    The CO2 did go up but only by a small amount. The large increase in CO2 concentrations since the 1850′s is due to the release of “fossil carbon” buried and unavailable for release into the atmosphere until we started mining, pumping and burning it.

    Ian Forrester

    Comment by Ian Forrester — 9 Jul 2007 @ 4:25 PM

  32. Re: 26
    Tim – I cant find the cite just now. I agree that Gavin’s explanation is consistent with AR4 and the finding of the new paper. The press release was misleading, and I owe Gavin an apology for my initial reaction to his reply.

    Comment by Sam — 9 Jul 2007 @ 4:38 PM

  33. RE: 30 Well, I believe Gavin knows about this and it is what he said in #5, that sulfates cool by reflecting energy before it is absorbed. The UC Irvine study says that Arctic warming and melting (between 35 to 94 percent) is caused by dirty snow. Black carbon could then be responsible for almost all observed warming and melting in the Arctic. This indicates we need further studies since it is possible that almost all warming in the Arctic is due to black carbon.

    The significant question is how much warming is due to carbon black and now much to other factors. There are three possible outcomes:

    Black Carbon is low end (35 percent) and CO2 theory still works.

    Black Carbon is middle range (~65 percent) and CO2 sort of works but is not as much a driver as predicted.

    Black Carbon is high end (94 percent)and CO2 is not a driver for global warming.
    -Basically, the dirty snow is melting the ice cap which caused more heat to be absorbed and releases the trapped methane. This warms the water cause a slight NH warming.

    So this becomes something we can test now and would want to know to help the GCM accuracy.

    [Response: Possibility 4. There are multiple impacts on Arctic temperature both warming and cooling that can't be distinguished in a single factor study with no other constraints. You appear to want to believe that this is a zero sum game - if factor X is bigger than was thought before, factor Y must be proportionately smaller. This is simply a fallacy since there are factors A, B, C and D which all have uncertainies and since only the sum total of the factors is constrained you can't conclude that the error is in Y. Hard as it might be to believe, the sensitivity to 2xCO2 in the Arctic or elsewhere, is independent of the effects of black carbon, ozone, methane or sulphates. - gavin]

    Comment by Vernon — 9 Jul 2007 @ 5:15 PM

  34. Gavin I agree, I am just pointing out that it is not just CO2 as some seem to stress. That there are many aspects and based on the UCI study, we need more information to determine the relationship between various aspects.

    Comment by Vernon — 9 Jul 2007 @ 5:40 PM

  35. Re: Comment by Vernon � 9 Jul 2007,5:15 pm

    Hansen and Nazarenko
    http://www.pnas.org/cgi/reprint/2237157100v1.pdf
    have a discussion of the forcing due to soot through change in albedo.
    The first sentence of the Summary:
    “The soot effect on snow albedo may be responsible for a quarter of global warming.”

    Now that I am on the subject of Hansen: In Phil. Trans. Royal Soc. A (2007), v365, pp. 1925-1954, Hansen et al. argue for an ice sheet albedo flip mechanism to explain abrupt glacial terminations. They point out that the timescales seen in paleo records reflect the timescales of the NH spring insolation forcing and not the fastest timescales possible for icesheet disintegration; i.e. these paleo timescales are upper bounds, rather than lower bounds for icesheet decay. A case is made that the appropriate climate sensitivity including albedo flip effects is 1.5C/(W/m^2) rather than 0.75C/(W/m^2). (There is also some discussion of black carbon effects). In sum, the possibility that substantial melting can occur on timescales as short as a century cannot be ruled out.

    I really shouldn’t look at Mercer and Hansen in the same afternoon…

    sidd

    Comment by sidd — 9 Jul 2007 @ 6:09 PM

  36. Vernon said, “…we need more information to determine the relationship between various aspects.”

    We always need more information. The question is whether the information will change the conclusion that we have to address this threat. CO2 forcing is the part of the equation we know best. It is constrained by several independent lines of evidence. In the extremely unlikely event that we were to find a forcing that we had not anticipated, it would not affect CO2 forcing, but more likely one of the forcings where uncertainty is greater (e.g. aerosols). So pumping more CO2 into the air would still result in significant warming.
    Now let me explain why it is a very bad idea to wait to act. CO2 is increasing exponentially in the atmosphere, and we know that the climate has positive feedbacks as well as negative. That is not a recipe for stability. What is more, we don’t know when these positive feedbacks kick in with a vengeance. We know it hasn’t happened yet, so maybe if we are lucky we can take some common sense actions, we can slow the warming enough to buy time so we can develop technologies and strategies mitigate the threats and take advantages of any benefits in a warmer world. The advantage of acting now is that we have a bit longer before the positive feedbacks kick in, AND people aren’t panicked. The latter is particularly important because people do foolish things when panicked–like wrecking the economy, electing authoritarian rulers, etc. Time is an awfully precious commodity when you’re talking about a system with positive feedbacks.

    Comment by ray ladbury — 9 Jul 2007 @ 8:40 PM

  37. I am rather puzzled by some of this. If I understand correctly, the argument is that DNA was found preserved in ice that’s much older than a time when it was assumed that the Greenland ice cap had melted completely, no? From which some people seem to conclude that the known sea level rise couldn’t have come from melted Greenland ice cap.

    But IIRC, the cap today is something like 2 km thick, on average. It seems obvious to me that if say 90% of that had melted, that’d leave a 200 meter thick layer ice cap, and still been within error limits for sea level rise. Where am I going wrong?

    Comment by James — 9 Jul 2007 @ 8:58 PM

  38. Re #36: James — You could be right, but most assume that about half of the sea level rise resulting from melting of some of the West Antarctic ice sheet.

    Comment by David B. Benson — 9 Jul 2007 @ 9:19 PM

  39. I was under the impression that ice core sites were typically chosen to minimize the extent to which the ice had moved in the past, in order to minimize folding and jumbling of ice layers. It seems to me that sites with relatively little ice movement would also be highly stable in terms of presence and thickness of ice. Doesn’t this result in a strong bias toward sites more likely to have ice (at any given time) than randomly selected sites of similar latitude and altitude? How did the researchers account for this?

    Comment by llewelly — 10 Jul 2007 @ 1:23 AM

  40. Re #27. In his account of the Voyage of the Beagle, Darwin described his encounter with un-clothed folk of Tierra del Fuego who met the Beagle in their canoes: “..a woman, who was suckling a recently-born child, came one day alongside the vessel, and remained there out of mere curiosity, whilst the sleet fell and thawed on her naked bosom, and on the skin of her naked baby!”

    Inferring temperature form clothing assumes others are as soft as us :)

    Comment by biffvernon — 10 Jul 2007 @ 2:22 AM

  41. Read this last night. Even CNN who tries at least to report the effects of global warming and climate change indicators, often times like to make controversy. The article on CNN.com first mentions that half a million years ago, greenland was “green” and that the climate was “different” then, in one sentence at the bottom (when most readers will loose interest) mentions what RC did about the dating potentially being only 116k years old. It’s so annoying.

    Here’s the link. Thought I’d stop by and drop it off here. Sorry if its been posted : I find it funny that theres an article on CNN about this a day after RealClimate.org posts a blog about it.

    http://www.cnn.com/2007/TECH/science/07/06/oldest.dna.ap/index.html

    Comment by Chris S — 10 Jul 2007 @ 9:18 AM

  42. Wikipedia comes to the rescue again.

    http://en.wikipedia.org/wiki/Greenland_Ice_Sheet_Project

    A quick discussion about the reasoning behind the locations of various ice cores on the Greenland Ice Sheet.

    Comment by Andrew Sipocz — 10 Jul 2007 @ 9:41 AM

  43. RE: 36 Ray, if the Arctic warming is possibly due to black carbon, what studies have been performed to support Gavin’s argument, that sulfates are causing cooling which is masking CO2 based warming? If there are no sulfates doing the cooling, and the dirty snow is doing the warming (for this argument, taking the high figure) then where is the signal for CO2 based warming? In fact, this leads to the question – is dirty snow warming the Arctic and the warming Arctic causing NH warming? This argument is within the bounds of the UCI studies results.

    [Response: You keep repeating the same statement, and you will keep getting the same answer. The whole premise of your BC vs. CO2 question is simply false. - gavin]

    Comment by Vernon — 10 Jul 2007 @ 10:40 AM

  44. Gavin, why is it false? There is a known empirical source of Arctic warming (BC – which needs to be further studied) and a unknown amount of cooling (sulfates – which I cannot find a study of for the Arctic) and a theory of CO2 based warming. If the study for the sulfates exists, then there would be empirical proof of cooling. These would either support or not support the Theory of CO2 based warming. I am asking where the study is for sulfates?

    [Response: If you want to see what all the different effects of all the different forcings are, try reading Hansen et al 2005 or 2007. There you have 14 different forcings (including sulphates and BC and CO2), conveniently grouped into only 8 experiments, and where you can see the different effects on the Arctic and the globe. Only the sum total of the effects is constrained (since the Earth has only run one experiment for us), and the true attribution to any one element has to be assessed using models that include all of the effects. The truth is that this is complex and jumping to conclusions based on simplistic readings of press releases just isn't going to lead you to enlightenment. - gavin]

    Comment by Vernon — 10 Jul 2007 @ 10:49 AM

  45. Re 34 Vernon: “Gavin I agree, I am just pointing out that it is not just CO2 as some seem to stress.”

    But why do you then assume for argument that carbon black accounts for 95% of Arctic melting and warming and ignore all other factors?

    Comment by Jim Eager — 10 Jul 2007 @ 11:03 AM

  46. RE:45 well, it could be because a UC Irvine study indicates that it is. See #5. That is why I am looking for a study of sulfates to support Gavin’s argument that the CO2 forcing is hidden by the sulfate cooling. I may have miss read the Hansen 2005, but I though it said that “The aerosol scenario in our model uses estimated anthropogenic emissions from fuel use statistics and includes temporal changes in fossil-fuel use technologies” and I did not see any listed sulfate studies for the Arctic. Are we now assuming that sulfates are going to be homogeneous? If so, where is the studies that supports that position?

    Models are nice but where are the empirical studies that support this in light of UCI’s study of Arctic warming? That is why I keep asking the same question.

    [Response: But the Irvine study is a model.... and if you can't find the Hansen discussion on the role of aerosols, go here and generate the plots for yourself: http://data.giss.nasa.gov/modelE/transient/Rc_ij.1.08.html - gavin]

    Comment by Vernon — 10 Jul 2007 @ 11:24 AM

  47. Vernon, you’re using the word “theory” as though it meant “speculation” aren’t you? You have the notion that if you can explain everything with one factor, the others can be assumed inconsequential?

    Consider: your childhood allowance on an annual basis may have been about equal to your parents’ annual tax refund from the IRS. That doesn’t mean you can zero out any other possible forcings and feedbacks to understand the family budget.

    Comment by Hank Roberts — 10 Jul 2007 @ 12:57 PM

  48. Re #38: [Re #36: James --- You could be right, but most assume that about half of the sea level rise resulting from melting of some of the West Antarctic ice sheet.]

    Yes, I understand that, but it wasn’t really my question. It appears that the reasoning uses a binary “melted/not melted” function for the Greenland ice cap, while to me it seems that the “not melted” state has a lot of room for changes in thickness, and hence volume of water in the oceans, while most of the land area of Greenland is still ice-covered.

    The difference, I think, is that Greenland’s ice would mostly just melt, while the West Antarctic ice is held back by gounded ice shelves, so that a small rise in sea level might trigger large increases in glacial flow. No doubt that’s over-simplified, but is it fundamentally wrong?

    Comment by James — 10 Jul 2007 @ 1:12 PM

  49. When I read the media reports, my thinking was, with a BAU scenario (to which we seem committed), it’s probably going to get a lot hotter than 125,000 yrs ago, so the fact that there was ice in that era means all the more ice to be melted in our anthropocene era. It doesn’t look good. We could be headed toward a 55 mya scenario, not a 125,000 yrs ago scenario. And then all the black soot melting it faster. We’re in very bad shape, I’d say.

    ***********************

    Another media report on the Western U.S. drought/fire conditions last night. The U of AZ scientist more or less indicated it was due to warming (and concomitant dryness/evaporation & wind patterns — sounded a bit tautological to me), but when the reporter pressed her if it was due to our AGW & GHGs, she focused solely on the notion that there had been such natural drought fluctuations in the past and it could be a natural (not human induced phenom) now. Well, I’d like to add that it COULD BE due to AGW, as well. And what kind of evidence is there that we are due for a “natural” drought spell — she didn’t give one iota of evidence for that, while we do have a lot of evidence that GW is happening.

    Why is “natural” the default, and “human-caused” admitted only if we are 95% or 99% sure? How about “human-caused” as the default in this anthropocene era (since at least we can do something about the problem, and we would thereby feel more empowered), and “natural” only the back-up alternative possibility?

    Then if we’ve done all we could to reduce our GHG (thereby strengthening our economy and bank accounts in the process), and we find out later lo & behold it was only “natural,” no harm done & we can use our savings to help us adapt to the “natural” problem.

    Comment by Lynn Vincentnathan — 10 Jul 2007 @ 1:49 PM

  50. Lynn, empowered, also means responsible, that’s why people are so reluctant to admit AGW, among other things. It was so much nicer, in the old days, when God was responsible for plague epidemics, gangrene, volcanic eruptions, hurricanes and even grandma’s lethal CHF exacerbation. Then, it was out of our hands, and, as terrible as it sounds, that carries some freedom. Now, we know better, but we don’t really want to be responsible, we still want the freedom.

    Comment by Philippe Chantreau — 10 Jul 2007 @ 2:39 PM

  51. This article:

    http://www.suntimes.com/news/otherviews/450392,CST-EDT-REF30b.article

    “Alarmist global warming claims melt under scientific scrutiny”

    cited a paper that discussed the dynamics and trends in glacier retreat and advance in the western Himalayas. The article, I fear, made up the quote it purportedly drew from the paper. The issue of Himalayan ice is not very related to the Greenland issue, but the distortion (or media modification) is closer. Was this an instance of deliberate and direct misrepresentation? And what can we do about it if it was?

    Comment by Justin — 10 Jul 2007 @ 3:25 PM

  52. There’s an item in today’s “NY Times”, that doesn’t mention the stability of instability of the Greenland ice sheet, but it quotes Dr. Willerslev as saying “…I think it’s very likely that what we are seeing is vegetation from and insects from the last time it was ice free.”
    http://www.nytimes.com/2007/07/10/science/10observ.html?_r=1&ref=science&oref=slogin

    One thing for certain is that one half million years ago, or 120,000 years ago or even about 1000 years ago when Eric The (infra?)Red went ashore on Greenland,there weren’t nearly 7 billion bipeds around, using energy at a prolific rate.We’re consuming about 2000 watts each, with developed countries using 5 times that number, and highly populated areas like India and China are becoming developed. This is unprecented and is certainly much different from anything that’s happened in the past, and should prevent us from becoming too complacent about even remote possibilities respecting the Greenland and West Antarctic ice sheetsl.

    Comment by Lawrence Brown — 10 Jul 2007 @ 3:47 PM

  53. Re Justin (#51)

    The link to the article was broken.

    I have fixed it below:

    Alarmist global warming claims melt under scientific scrutiny
    June 30, 2007
    BY James M. Taylor
    http://www.suntimes.com/news/otherviews/450392,CST-EDT-REF30b.article

    Taylor quotes the essay as saying:

    “Glaciers are growing in the Himalayan Mountains, confounding global warming alarmists who recently claimed the glaciers were shrinking and that global warming was to blame.”

    The second paragraph from the abstract (entire paper at link):

    The impact of observed seasonal temperature trend on runoff is explored using derived regression relationships. Decreases of 20% in summer runoff in the rivers Hunza and Shyok are estimated to have resulted from the observed 1°C fall in mean summer temperature since 1961, with even greater reductions in spring months. The observed downward trend in summer temperature and runoff is consistent with the observed thickening and expansion of Karakoram glaciers, in contrast to widespread decay and retreat in the eastern Himalayas. This suggests that the western Himalayas are showing a different response to global warming than other parts of the globe.

    Conflicting Signals of Climatic Change in the Upper Indus Basin
    H. J. Fowler, D. R. Archer
    Journal of Climate, 19(17), 4276â??4293 (2006)
    http://www.staff.ncl.ac.uk/h.j.fowler/fowler&archer_JC2006.pdf

    Taylor’s “quote” appears no where in the essay. However, Taylor’s “quote” is showing up a whole lot:

    Google search: “Glaciers are growing in the Himalayan Mountains”

    997 hits and counting…

    Comment by Timothy Chase — 10 Jul 2007 @ 4:31 PM

  54. Oh, the Heartland Institute. Those kooks! Those guys couldn’t even get through the abstract of a scientific paper. I think some letters to the editor of the Sun-Times are in order–maybe a couple thousand of them.

    Comment by Ray Ladbury — 10 Jul 2007 @ 5:22 PM

  55. Re Ray Ladbury (#54)

    The paper:

    Conflicting Signals of Climatic Change in the Upper Indus Basin
    H. J. Fowler, D. R. Archer
    Journal of Climate, 19(17), 4276â??4293 (2006)
    http://www.staff.ncl.ac.uk/h.j.fowler/fowler&archer_JC2006.pdf

    … actually looks fairly interesting. Apparently changes in the large scale atmospheric circulation patterns involving the monsoon – heavier rains in Nepal, although some have implicated the aerosol effects of the Asian Brown Cloud. Cooler temperatures during the summer, warmer temperatures during the winter. The Tibetan Plateau might be throwing us a bit of a curve-ball.

    Too bad the evil zombies are twisting it to their ends – but I suppose they would do that with anything they could. At this point I would say they are nearly to the shores of the Phlegethon.

    Comment by Timothy Chase — 10 Jul 2007 @ 6:16 PM

  56. Ray, you’ll never compete until you can match what they pay for ad space.
    Full page in the NYT today.

    Comment by Hank Roberts — 10 Jul 2007 @ 6:59 PM

  57. That the Karakoram glaciers are rebuilding a little is not that surprising. Here in NZ we are experiencing a marked increase in the frequency and severity of westerly weather patterns that are no doubt slowing the AGW decline of the galciers on our western-facing alps. But overall snow mass will be continuing downward as warmer temperatures (probably partly created by the fohn effect of the stronger westerlies) hit the east.

    Are the reductions in outflow from Karakoram glaciers due to changes in temperature, or are they driven (at least in part) by the fact that there is less ice left to melt?

    Comment by Nigel Williams — 10 Jul 2007 @ 7:57 PM

  58. Hank Roberts (#56) wrote:

    Ray, you’ll never compete until you can match what they pay for ad space.

    Full page in the NYT today.

    Funded by Exxon.

    Exxon will next review the groups it funds in November this year. Cohen would not confirm if there were plans in place to remove some of the more contentious names from its funding lists. The grants it gives are not huge. Two controversial groups, the Heartland Institute and the George C Marshall Institute, for example, received about $200,000 between them in the current financial year.

    Exxon Mobil: A proud oil giant comes to the climate change policy table
    3 July 2007
    http://www.climatechangecorp.com/content.asp?contentid=4859

    Above the table $200,000 between Heartland and Marshall. Hard to believe that is what is financing Taylor’s campaign. (Deltoid has dug up a bit where he also points out that these are glaciers “feeding just one out of seven of the major rivers coming out the Himalayas…”) Heartland seems to be taking tips from the Discovery Institute in how they get out the message though, calling their opponents “fascists,” and their propaganda oftentimes appeals to the groups. Bigger bang for the buck – when Daddy Big Bucks wants to do things on the cheap.

    Comment by Timothy Chase — 10 Jul 2007 @ 10:47 PM

  59. I don’t think there is any shame on the scientists here (making comments that might be misinterpreted). It is true that the lead scientist in the study, Eske Willerslev, is reported as saying “Part of the ice cap is more stable than previously thought”. But according to this article in Bloomberg.com, he also went on to say, as part of an amplification of the meaning of this study,: “It doesn’t mean that we should just continue to put out CO2 into the atmosphere. The sea-level rise that you experienced during that last warm period must’ve come from somewhere. People in the Netherlands won’t care if it’s the Greenland ice cap or the Antarctic ice cap when they’re sitting in their rubber boats.”

    It is not the scientist’s fault if a tiny fraction of what they say is taken out of context, grossly exaggerated and cynically misused by people who are pursuing their own, mischievous agenda.

    Comment by John Monro — 11 Jul 2007 @ 12:37 AM

  60. Re: The glaciers of Karakoram:

    http://news.nationalgeographic.com/news/2006/09/060911-growing-glaciers_2.html

    Excerpt from the article:

    Lonnie Thompson, a paleoclimatologist and glacier expert at Ohio State University in Columbus, thinks the latest findings might be a short-term trend only.

    “My guess is that the glaciers in [Haley and Fowler's] area of study might find short-term benefit where increased winter snowfall outweighs summer melt,” Thompson said.

    “[But] it’s likely these glaciers will follow the same pattern of those in Sweden and Norway, which were growing until 1999 due to increasing winter snowfall even as temperatures rose.

    “However, since 1999 these same glaciers are now retreating.

    “The balance of glaciers globally shows retreat and even acceleration in the rate of retreat,” Thompson stressed. (Related news: “Greenland Glaciers Losing Ice Much Faster, Study Says” [February 2006].)

    It may take many years to understand climate change’s lasting effects on Pakistan’s glaciers.

    — End excerpt —

    Comment by Anders Lundqvist — 11 Jul 2007 @ 3:16 AM

  61. OFF TOPIC – SUN NOT TO BLAME FOR AGW

    Mike Lockwood a physicist at the Appleton Rutherford labratory in the UK apparantly dismayed by the TGGWS carried out this research and has consluded that the Suns activity is no to blame for the 0.3 of warming of the earths surface since the 1980′s.

    http://uk.reuters.com/article/domesticNews/idUKL101501320070711?pageNumber=2

    http://environment.guardian.co.uk/climatechange/story/0,,2119695,00.html

    Thats that then, probably not but lets hope that this story is well reported globally.

    Comment by pete best — 11 Jul 2007 @ 4:32 AM

  62. re 51, 53: melting glaciers

    Same kind of story happened a few weeks ago when France and Switzerland scientists published a paper on the study of the highest European glacier:

    Very high elevation Mont Blanc glaciated areas not affected by the 20th
    Century climate change
    C. Vincent1, E. Le Meur1, D. Six1, M. Funk2, M. Hoelzle3 and S. Preunkert1
    http://www-lgge.obs.ujf-grenoble.fr/axes/glaciers/Publications/Vincent2006MontBlancJGR.pdf

    When reading the article entirely, you see that the writers are stating the very high altitude Mont Blanc glacier has shown no particular melting trend during the 20th century, and explain why. The article states:
    “The 20th Century climate warming affected the atmospheric temperature in the Alps by +1°C (Böhm et al., 2001). However this change did not significantly affect the ice deformation rate in the high-altitude ice fields since the ice temperature remains far below the melting point and therefore keeping the glacier frozen to its bed.”
    Translation, the glacier is still too high to be affected by temperature changes. Note it is actually stated that there was a 1°C warming trend during 20th century.

    The article concludes:
    “Over the next 100 years, according to climate warming scenarii, a significant part of precipitation could become rain above 4300 m a.s.l. which could warm up the deep firn and ice. Some studies show that substantial warming of the firn temperature at shallow depths has taken place over the last few decades (Lüthi and Funk, 2001., Suter et al., 2001). Should this warming reach the bottom ice, the ice dynamics would be greatly modified.”
    Basically, if warming goes on, the glacier could become much more unstable than it has been by the past.

    It is also to be noted the same scientists published a lot of articles on the subject, showing the tremendous impacts of global warming on lower altitude Alp glaciers:
    http://www-lgge.obs.ujf-grenoble.fr/axes/glaciers/Publications/
    See specially:
    Ice ablation as evidence of climate change in the Alps over the 20th Century
    C. Vincent, G. Kappenberger, F. Valla, A. Bauder, M. Funk and E. Le Meur.
    J. of Geophysical Research, Vol 109, No D10104, pp 1-9.

    But of course, some people apparently stopped reading at half the title of the paper, saw the words they wanted to see in a scientific paper (“not affected” seems to be the key here), and went cherry picking here and there to state the lines of the article they’d like.
    And these are a few examples of what you can find on the net now, based on this article:
    http://www.iceagenow.com/Glaciers_Growing_in_France_and_Switzerland.htm
    http://www.worldclimatereport.com/index.php/2007/06/26/mont-blanc-glaciers-refuse-to-shrink/
    http://www.libertypost.org/cgi-bin/readart.cgi?ArtNum=193090

    I feel very sorry for those 6 guys who probably made a hell of a job to publish this article, and finally see their work misinterpreted and twisted this way.

    Comment by nicolas L. — 11 Jul 2007 @ 5:01 AM

  63. Only 6m higher water levels despite a 2celsius increase in global temperature? (Although on the BBC it was quoted as 5Celsius).

    I guess us Brits can go back to sleep then. London is sinking into the mud it is built on far faster than global warming is likely to cause sea levels to rise.

    Comment by Ryan Stephenson — 11 Jul 2007 @ 5:38 AM

  64. [[Only 6m higher water levels despite a 2celsius increase in global temperature? (Although on the BBC it was quoted as 5Celsius).

    I guess us Brits can go back to sleep then. London is sinking into the mud it is built on far faster than global warming is likely to cause sea levels to rise.]]

    I don’t think you understand the seriousness of the situation. Rising seawater doesn’t have to drown a city to make it uninhabitable. All it has to do is seep into the aquifers and back up the sewers. With no fresh water supply and sewers backed up all over the city, Miami and New York and London will be uninhabitable long before they are under water.

    Comment by Barton Paul Levenson — 11 Jul 2007 @ 7:00 AM

  65. Timothy, I haven’t read the paper, but you are right, based on a quick skim, it does look interesting. The thing is that the paper may be quite reasonable, but no matter what it says, Heartland will spin it to its agenda. I can’t figure these guys out. Do they really believe their spin or are they so cynical that they figure as long as they can buy up all the high ground, they’ll be fine? Or maybe they’re like former Interior Secretary James Watt who saw no point in conservation since “the Lord” would be back soon. What really amazes me, though, is that such ham-handed efforts actually seem to be effective. They ought to be simply laughed off the planet.

    Comment by Ray Ladbury — 11 Jul 2007 @ 7:12 AM

  66. RE: 47 Well, I do not expect this to be posted, but I figure why not give it a try.

    I generally accept the standard definition of a theory as a well-substantiated explanation of some aspect of the natural world; an organized system of accepted knowledge that applies in a variety of circumstances to explain a specific set of phenomena.

    Keeping that in mind, here is what I understand and what I have issues with the Theory of CO2 based warming and would like to see addressed:

    The physics of CO2 as a green house gas I don�t question, however, I cannot find any examples of CO2 causing global warming. I can see where CO2 is lagging indicator in the historical record but not where it is a driver.

    The proxies used to show global temperatures for the last interglacial do not show a medieval warming or a little ice age, but they do not show late twentieth century warming either. If the proxies are not accurate with compared with current instrumented readings, then why were they accurate in the past?

    If the MWP and the LIA were regional only, then why are two sites good enough to get the global CO2 measurement? Ice cores from Vostok and Mouna Loa Observatory good enough to represent the globe, why don�t they just represent a region?

    One indicator of global warming is sea level rise but the actually satellite measurements show no rising trend for the last 10 years. The rising trends are based on tide gages.

    Finally, solar activity correlates better with global climate than CO2, which correlates poorly (lagging indicator and all). While correlation does not mean causation for solar activity, neither does it for CO2. So, why does solar activity correlate with the global climate? I do not see an answer to that in the CO2 Theory.

    Normally, I would not bother to watch scientist argue over the flavor of the month theory. But unlike the change from classical to relativity, to quantum physics or the move from string theory to 11 dimension theory, climate theory has gone political. Based on a model it is being proposed that all society be changed. With that level of impact, empirical evidence is needed to support the CO2 model, and Gavin has not provided it. He says that UCI is wrong because Hanson is right, not able to point to any empirical studies.

    So, while I don�t expect this to ever get posted here, before I am going to accept this Theory, I want to see it proven empirically.

    Comment by Vernon — 11 Jul 2007 @ 7:15 AM

  67. RE: Timothy’s #58
    The administration apparently has ad hommed AGW and all of us who care about it away:

    “[Former Surgeon General Carmona] described attending a meeting of top officials in which the subject of global warming was discussed. The officials concluded that global warming was a liberal cause and dismissed it, he said.

    â??And I said to myself, â??I realize why Iâ??ve been invited. They want me to discuss the science because they obviously donâ??t understand the science,â?? â?? he said. â??I was never invited back.â??”

    http://www.nytimes.com/2007/07/11/washington/11surgeon.html?_r=2&hp=&adxnnl=1&oref=slogin&adxnnlx=1184155421-sCHadWKv3yoCNLEcjcKDXg

    Comment by ghost — 11 Jul 2007 @ 7:24 AM

  68. “I don’t think you understand the seriousness of the situation. Rising seawater doesn’t have to drown a city to make it uninhabitable. All it has to do is seep into the aquifers and back up the sewers. With no fresh water supply and sewers backed up all over the city, Miami and New York and London will be uninhabitable long before they are under water.”

    They will indeed – regardless of whether the rising sea levels are caused by land ice melting or because of land subsidence. In the case of London the land subsidence is happening anyway, so it will become expensive to keep it inhabitable due to the subsidence. Not only that, it will probably require a lot of horsepower to turn London into the Venice of Northern Europe. The point remains that global warming need not concern Brits any more than land subsidence currently does, although no doubt Wimbledon will be wet again next year, which could be irksome.

    Comment by Ryan Stephenson — 11 Jul 2007 @ 8:12 AM

  69. Dear Gavin;

    My apologies, I just read your response at the top of this series of comments and noticed that in review of black carbon that though it may be a contributor that it is not significant enough to account for the apparent ice field reductions. You suggest that the only significant explanation is likely CO2 or what appears to be a Greenhouse Gas radiant barrier.

    I had read much of Dr. Hansen’s and your work in relation to working models and the apparent radiative increase reaching the earths surface due to the increase in Greenhouse gases and the approximate value of added radiant value appears to be about 2.6 Watts/Meter^2. In regards to this estimate has there been actual measurements in the ice fields that supports this modeled value? Secondly, have studies exclusively done on the site excluded any other possible ice field melting contributors?

    (My apologies for sounding like a Doubting Thomas; however, like most, I suspect, empirical evidence support for modeled theories helps greatly with the comfort level with the modeled evidence. Plus I like seeing non-manipulated forecasts that track close to empirical evidence before assigning much confidence to the model.)

    Dave Cooke

    Comment by L. David Cooke — 11 Jul 2007 @ 9:04 AM

  70. >65, James Watt
    Ray, remember there are liars and whackos on all spokes of the political wheel.
    That particular piece of bogosity you attribute to Watt was made up, I gather by someone writing for Grist, and published by someone who failed to check their authors’ cites. Bill Moyers is among those who fell for the misattribution, and apologized.

    Comment by Hank Roberts — 11 Jul 2007 @ 9:14 AM

  71. #64, #67 – England under water.
    will I be late in asking why England should have more problems than I don’t know, say, Holland, which manages to cope lying largely beneath sea-level? As the man says – I have no fear, ’cause London is drowning and I live by the river..

    Comment by Alan K — 11 Jul 2007 @ 10:05 AM

  72. Ryan Stephenson (#63) wrote:

    I guess us Brits can go back to sleep then. London is sinking into the mud it is built on far faster than global warming is likely to cause sea levels to rise.

    I think five meters in this century unlikely although several are a distinct possibility. But things like the heat wave of which hit the continentals will probably become more commonplace.

    I’ve heard that the London fog has gone the way of the dodos, but you blokes weren’t especially fond of it anyway. I understand its been getting drier out there so far, that they are already suggesting that you cut back on watering your lawns and plant different flora for your gardens, but all-in-all, from what I see you will have it easier than those us who live on this side of the pond or those of us in Asia or Australia.

    It looks like the states are going to be hit especially hard in the latter part of this century. Falling agricultural output due to droughts affecting the states and Asia will in all likelihood raise prices across the globe – as will falling fish harvests, but yes, you should have an easier time of it I believe.

    Comment by Timothy Chase — 11 Jul 2007 @ 11:57 AM

  73. Re #67: [The point remains that global warming need not concern Brits any more than land subsidence currently does...]

    That would be true if rising sea levels were the only effect of climate change. (Indeed, since I live at a higher elevation than the highest point in the British Isles, I should have even less to worry about.) Unfortunately, it seems as though rising sea levels are going to be only a minor part of the problem.

    Comment by James — 11 Jul 2007 @ 12:21 PM

  74. RE: 71, more wisdom from the Clash, actually kind of eerie and prescient:

    The ice age is coming, the sun’s zooming in
    Meltdown expected, the wheat is growing thin
    Engines stop running, but I have no fear
    ‘Cause London is drowning, and I live by the river

    Comment by Sam — 11 Jul 2007 @ 12:22 PM

  75. #72 Timothy Chase

    I understand its been getting drier out there so far

    It’s been raining heavily most of the last month in the UK, and there have been pretty bad floods in several areas! April was ~5C above the average and 1-2C above the average for the remaining months this year. Qualitatively I remember it being frosty in the winter more often than now, so I’d argue the temperature increase is perceivable.

    Comment by SomeBeans — 11 Jul 2007 @ 12:22 PM

  76. #66 Theory not proved empirically…

    Vernon,
    As a complete “civilian” in this subject, it matters to me when something doesn’t make sense to somebody else.

    One thing you should understand: RealClimate does not stifle debate nor does it discourage dissent. It should not surprise you to see a meritorious post published. You raise issues which no doubt appeal to many.

    Of course, those from the science community will perhaps look at your post as naive or agenda-driven, or perhaps they will simply lament that the politicization of this issue has led to a great deal of public confusion.

    The truth of course is that much of this is fuzzy. Scientists do not understand all of the relationships which lead to shifts in climate; the global mean temperature is not nearly as important as the ways in which regional climates change, especially when they become drier; the models, as Gavin readily admits, do not incorporate all of the physics thought to be important. Anybody who wants to call climate science a guessing game will find plenty of evidence.

    However, your rational mind must know that the current state of climate science is built upon very thin layers of knowledge which have been gained over more than a century, with a great acceleration of that knowledge in the last 60 years or so. You must recognize that long before politics entered into the equation, real world observations were leading scientists in a direction: that CO2 is accumulating in the atmosphere, and that over time this will affect global temperatures. How much? How soon? and just, How? Are mostly unknown.

    One thing that can be generally stated: a warmer planet holds less frozen water. It holds less snow in the mountains and it holds less ice at the poles. This is a historical fact: when temperatures rise, so do sea levels.

    With regard to the Greenland ice sheet, the important point being made by Gavin was that a scientifically benign report was twisted by the P.R. people of science organizations, to imply that the report in some way undermined climate theory.

    In order for you, me or anybody to make real sense of climate science (to the extent that our limited experience allows us), we need to recognize spin and separate it from science.

    As to the specific issues you raised, you can research them yourself, and many of them are addressed right here at RC.

    Comment by Walt Bennett — 11 Jul 2007 @ 12:46 PM

  77. Re: Vernon at #66:

    You ask for proof, but you’re not going to find proof. You’re going to find “preponderance of evidence”. Gavin has several times pointed you to further information, as have others.

    Many of your questions are answered in articles here at Real Climate. Your concern about CO2 concentrations lagging temperatures in the historical record, for example, is really basic stuff and has been covered many times. The short answer is that you won’t find CO2 leading temperatures in the historical record, because you won’t find any industrial civilizations before ours priming the feedback-forcings cycle by pumping huge amounts of CO2 into the atmosphere. Your other issues are similarly addressed in other articles.

    I think you’re getting something of a rough reception, because you come here demanding proof and seem unwilling to go read with an open mind the stuff that’s already been written.

    Comment by shargash — 11 Jul 2007 @ 1:30 PM

  78. #66

    “If the MWP and the LIA were regional only, then why are two sites good enough to get the global CO2 measurement? Ice cores from Vostok and Mouna Loa Observatory good enough to represent the globe, why don’t they just represent a region?”

    They do both have regional characteristics, that’s a good insight. But nobody relies on only those two to represent the globe. There a a number of ice core sites from both polar areas and from glaciers. And many locations where CO2 is measured. The two you mentioned are just a couple of more famous ones.

    Keep on learning.

    [Response: CO2 is actually very well mixed in the free atmosphere and so you do only need a few measuring stations. You need many more for temperature anomalies... - gavin]

    Comment by Tom Adams — 11 Jul 2007 @ 2:22 PM

  79. RE: #76

    Hey Walt;

    What you shared with Vernon, likely applies to my questions as well in #69. I have to say that I have done research on as many .gov or .edu sites as I can, if the site does not require a professional affiliation or dues. From all the research I have attempted I have found that the main character of the data closely follows your synopsis. This raises the question as to how can such a strong case be built based on the data as you characterize it?

    This is not to belittle the work done, only that I am uncertain that the trend of the arrow appears so strongly to point in a certain direction. Though the balance of scientific work is clearly suggesting a warming event, it appears that there would not be a strong enough signature or “handprint”, if you will, to specify the hard values in the press and some of the articles.

    Granted the models are fantastic in comparison to the trending models of the 1970′s. What bothers me is when I attempt to build a model and populate it with representative data, the variance between the median and the mean would be enough to account for the current noted deviation in the Global Average Temperature. Hence, this is why I try so hard to see if the raw data, with notes, over the past 30 years collected by the various science expeditions could be placed in a publicly available share point. (The CDIAC data set has been a boon; however, as noted before by others, the move to a gridded model worries me a bit.) It is not that there is a denial of trust in the work of those who are professionals, it is an attempt for me to prove to myself that the data as they have portrayed it vindicates their hard work. (I find it helps me in my understanding when I get the chance to work it out for myself.)

    What makes it even more frustrating is when data is placed in public it has been massaged so that the delineation of local variance is lost. When combined with the error bars, in my analysis, the global warming signature disappears. (I guess I would rather have the data with the value flagged that it is likely an estimate taken from a nearby station. (With the estimate modified based on the comparative historic run of the instrument sets for that day of the year and time.)) What makes it exceedingly more difficult is I do not have the higher math skills to attempt a Fourier Analysis to attempt to retrieve the signal from what appears to be noise.

    As to specific help, I continue to fail to see that the GHG radiant energy is affecting local temperatures. These changes appear to be driven not by additional radiant heating; but, by changes in large scale atmospheric patterns. Has anyone seen anything describing how GHG radiative heating is changing the character of the Jet Stream or Zonal Barometric Pressure Waves?

    As to your comment about the popular press and media slant; I found 7 years ago the best bet is only to get your announcement that a new Study has been generated there. I usually try to go to the source or to a trusted site for the details. My thanks for your time in writing back to Vernon, I am sure he and I are not alone…

    Personally, I am impressed with the work that has been accomplished so far. When we the public, start complaining about the state of the science, we need to look first to ourselves. Proper funding over the last 40 years, in many areas, may have made a big difference in the state of the science today… My thanks to the professionals who persevered.

    Dave Cooke

    Comment by L. David Cooke — 11 Jul 2007 @ 2:47 PM

  80. Re#64 London is not built on the sort of mud one sinks into and the aquifers are not the sort that sea water can seep into. Sewage is already pumped. In due course the Thames Barrier at Woolwich will need to be improved but we have the technology to cope. But in Bangla Desh…that’s another story.

    (no relation to ‘Vernon’)

    Comment by biffvernon — 11 Jul 2007 @ 3:26 PM

  81. I (#58) had written:

    I understand its been getting drier out there so far…

    SomeBeans (#75) responded:

    It’s been raining heavily most of the last month in the UK, and there have been pretty bad floods in several areas! April was ~5C above the average and 1-2C above the average for the remaining months this year. Qualitatively I remember it being frosty in the winter more often than now, so I’d argue the temperature increase is perceivable.

    You are quite right. In fact I see that the amount of rain has been tending to increase over the years:

    Dave Watkins on Rainfall Trends in Cornwall
    http://www.people.ex.ac.uk/dcwatkin/rainfall_in_cornwall/index.htm

    … which I find a little odd since we had a fellow through here just recently who was complaining about too many sunfilled days. (I prefer the rain myself – which is part of the reason why I picked Seattle.)

    I would guess that this has something to do with the gulf stream shifting to the NE. It probably rains less often, but harder when it does rain.

    What I was going off of were my memories of 2005:

    High and dry
    The UK has its first hosepipe ban in nine years after a dry winter…
    Wednesday, 8 June, 2005
    http://news.bbc.co.uk/1/hi/magazine/4613851.stm

    Climate change threat to gardens
    Fields of sunflowers could replace the traditional English landscape
    The English country garden is unlikely to survive in the South East beyond the next 100 years, scientists say.
    Monday, 13 June, 2005
    http://news.bbc.co.uk/1/hi/england/4089044.stm

    River levels ‘as low as in 1976′
    Reservoirs and rivers are as parched as they were during the hot summer of 1976
    Monday, 4 April, 2005
    http://news.bbc.co.uk/1/hi/england/4410707.stm

    2005 was an especially dry year.

    But the temperatures are clearly on the rise:

    State of the Cornish Environment – 2002 Baseline Edition
    2.1 Climate Change
    http://www.cornwall.gov.uk/index.cfm?articleid=11616

    … and interestingly enough, 2005 didn’t even merit a mention for top ten temperature records, although 2006 did:

    2006 sets British heat records
    Feeling the heat: Plants’ behaviour is affected by the climate
    Several records for temperatures in Britain have been broken during 2006.
    Thursday, 14 December 2006
    http://news.bbc.co.uk/1/hi/sci/tech/6177663.stm

    However, when Ryan Stephenson (#63) states:

    Only 6m higher water levels despite a 2 Celsius increase in global temperature? (Although on the BBC it was quoted as 5 Celsius).

    … I believe what is going on is that the 2 Celsius is the increase in the global average temperature, whereas the 5 Celsius is the increase in the UK average temperature. The southern hemisphere won’t warm as much as the northern hemisphere, the tropics won’t warm as much as the higher latitudes, and the ocean won’t warm as much as the land. Being on the Atlantic might work to your advantage there, particularly with the direction of the jet stream and the Gulf Stream.

    Anyway, my apologies for my presumption.

    Comment by Timothy Chase — 11 Jul 2007 @ 4:00 PM

  82. This is not directly on-topic, but is breaking news about global warming studies:

    http://www.theage.com.au/news/national/solar-activity-cleared-of-global-warming-blame/2007/07/11/1183833599508.html

    Solar activity cleared of global warming blame

    James Randerson, London
    July 12, 2007

    Comment by Neil B. — 11 Jul 2007 @ 4:46 PM

  83. RE: 82 Unlike Professor Lockwood I do not see much of a drop in cosmic rays reaching Earth.

    http://cosmicrays.oulu.fi/Request.dll?Y1=1964&M1=Jan&D1=01&h1=00&m1=00&Y2=2007&M2=Jan&D2=01&h2=00&m2=00&YR=00&MR=00&DR=00&hR=00&mR=00&PD=1

    Comment by Gary — 11 Jul 2007 @ 5:43 PM

  84. Neil B (#82) wrote:

    This is not directly on-topic, but is breaking news about global warming studies:

    http://www.theage.com.au/news/national/solar-activity-cleared-of-global-warming-blame/2007/07/11/1183833599508.html

    Solar activity cleared of global warming blame.

    Good to see – otherwise we might have had a heck of a time bringing him in for questioning.

    Of course they are already arguing that if the solar years are cooling, this explains the cooling of the stratosphere – and as the upper and lower atmosphere go in opposite directions as the result of global warming, this explains the rising temperatures in the lower atmosphere. However, this asymmetry between the lower and upper atmosphere to changes in carbon dioxide levels, not solar output.

    An increase in solar output would warm both, and a decrease would cool both.

    Comment by Timothy Chase — 11 Jul 2007 @ 5:46 PM

  85. Completely off topic…

    Many seem to have the impression that the weather system, or at least a special case of it, has been proven to be caotic. However, they seem to get the impression that the climate system is assumed (by climate modellers) to be largely independent of initial data, or in other words is assumed to be a boundary value problem. Are they mistaken? And if not, is this a provable fact? I would appreciate answers with references.

    Best regards,

    Comment by Omar — 11 Jul 2007 @ 6:36 PM

  86. Hey Greenies!

    I’m assuming most of the followers of environmental issues have an opinion about Live Earth, which happened last weekend…

    I think it’s important to listen to the skeptics in order to make informed decisions about climate change. This man makes some interesting points, even if they’re just points to bounce opposite ideas off of:

    Celebrity Earth?
    http://www.orato.com/node/2974

    Celebrity Earth?

    what do you guys think?
    http://www.orato.com

    Comment by Heather Wallace — 11 Jul 2007 @ 6:52 PM

  87. Re #79: [This raises the question as to how can such a strong case be built based on the data as you characterize it?]

    What you seem to miss is that the case for AGW is not built on that temperature data, it’s built on a) an observed increase in CO2 (known to be human-caused); and b) known radiation physics. The data is confirmation: the models predict such-and-such patterns of temperature increases, and since we find that actual temperatures match those predictions pretty well, it gives confidence in the models.

    On the other hand, if the observed temperatures didn’t match the model predictions, people would go looking for reasons – either flaws in the models, or bad measurements. The weather site validation people want to do this in reverse. They want to cast doubt on the models’ predictions, so they attack the measurements in hopes that they can show that the match was spurious, and that therefore the models are wrong.

    Comment by James — 11 Jul 2007 @ 8:04 PM

  88. Re: #83 (Gary)

    Unlike Professor Lockwood I do not see much of a drop in cosmic rays reaching Earth.

    I do, even in the graph you link to. And you will too, if you subtract away the solar-cycle variations. That’s what Professor Lockwood did, very adeptly.

    Comment by tamino — 11 Jul 2007 @ 8:04 PM

  89. Re #85: Omar — This has been treated, in considerable detail, here on RealClimate. I encourage you to read previous threads, include comments. Consider the important links on the sidebar(s).

    You’ll find that indeed, climate models are not chaotic. As experimentally verified.

    Comment by David B. Benson — 11 Jul 2007 @ 8:08 PM

  90. #81 Timothy Chase

    It’s true that the general impression of rainfall in the UK is of reduction, however it just so happens that v. recently it’s been very wet (so I’m feeling a bit bedraggled). I think, compared to other countries, the UK has relatively large variations in climate across a relatively small area. You’ll also tend to hear more media reports from London and environs which is generally drier than the more westerly areas of the country.

    I think 2C is a better estimate of our current warming over average for this year (April was pretty exceptional).

    Should you wish to relocate to the UK, I suggest Wales may provide just the sort of rainfall you’re looking for!

    #86 Heather
    Not really sure how many of us would describe ourselves as ‘greenies’. Personally I’m pro-GM, pro-nuclear (power) and pro-”dumping old oil platforms in deep ocean” (as the best of a set of non-ideal choices) – none of which are particularly green positions. I am pro-science, and I don’t see politics (or pop stars) as a way of answering scientific questions.

    Comment by SomeBeans — 12 Jul 2007 @ 2:49 AM

  91. @SomeBeans:

    It is indeed very wet here this year. Apparently this is due to warmer temperatures ove rthe oceans. This causes higher evaporation of course, and thus greater cloud cover. Clouds are white on top so they reflect a lot of radiant heat. Under the clouds, the temperature tends to be lower, and over land the clouds lose their ability to retain water vapour and thus we get rain. It is also colder than a June without cloud cover (by about 10Celsius), since the clouds block the radiant heat energy. During the day that is. During the night the temperature is warmer, as the clouds help to keep the heat in whilst there is an absence of radiant heat from the sun. Due to this heat retention affect, the MEt office reports June temperatures as being higher than usual for June. This is partly because MET office temperatures are alwas measured in the shade, so direct radiant heat energy has less impact, and daily temperatures are averaged over a full 24 hours. Thus it feels cold during the day but actually it measures out warmer than an average June.

    And the upshot of all this? Well my garden is loving this weather. The grass is growing like crazy. But I shall fly off to the Canary Island with the family in October, to get some sun.

    Comment by Ryan Stephenson — 12 Jul 2007 @ 4:54 AM

  92. SomeBeans @90 “It’s true that the general impression of rainfall in the UK is of reduction, however it just so happens that v. recently it’s been very wet”

    The recent weather is a monsoon system apparently. It seems that there is a monsoon for NW Europe (it’s a result of the landmass heating up as we hit the long days of summer, heating air over the land, which convects and sucks in weather systems from the Atlantic) but it’s usually pretty weak and so not that noticeable to laymen (other than the regular laments about why Wimbledon gets rained off all the time).

    Every now and then you get a year (like this year) when it’s stronger and more long lived than usual which is when people sit up and take notice. There’s been some speculation that AGW will tend to reinforce the European monsoon and thus make the ‘noticeable’ years more frequent, but I don’t think this is a solid prediction yet.

    Regards
    Luke

    Comment by Luke Silburn — 12 Jul 2007 @ 6:12 AM

  93. [[Or maybe they're like former Interior Secretary James Watt who saw no point in conservation since "the Lord" would be back soon. ]]

    This “quote” of James Watt has become famous, but if you read the original transcripts, that’s not actually what he said. What he said is that since he didn’t know when the Lord would return, it makes sense to take care of the land in the meantime — exactly the opposite of what is usually attributed to him.

    I didn’t vote for Reagan and I don’t think Watt was a great choice for Interior, but this particular quote is an urban legend.

    Comment by Barton Paul Levenson — 12 Jul 2007 @ 7:33 AM

  94. [[Finally, solar activity correlates better with global climate than CO2, which correlates poorly (lagging indicator and all).]]

    Solar activity has been approximately flat for the last 50 years, so it can’t account for the sharp warming of the last 30 years. We’ve been measuring the solar constant from satellites like Nimbus-7 and the Solar Maximum Mission. The rise in temperature of the last 30 years can only be accounted for by taking greenhouse gases into account.

    Comment by Barton Paul Levenson — 12 Jul 2007 @ 7:37 AM

  95. [[The point remains that global warming need not concern Brits any more than land subsidence currently does, although no doubt Wimbledon will be wet again next year, which could be irksome. ]]

    It will concern them if it messes up their agriculture, which global warming is likely to do.

    Comment by Barton Paul Levenson — 12 Jul 2007 @ 7:38 AM

  96. “It will concern them if it messes up their agriculture, which global warming is likely to do. ”

    “Likely”? Well the last 60 years of “global warming” certainly hasn’t. I would be more worried about mad cow disease – to keep things in some sort of perspective. Global cooling in the shape of the next ice-age is a different matter. That will be bad news for the whole world, and not much chance of escape.

    However, there is little chance of glabal warming being a problem for food supplies in the UK. UK food production meets the needs of 60% of the population – the rest is imported. However, food production accounts for only 1% of GDP. Even if food production was to decline dramatically its effect on GDP would be small. Consequently the possibility to import food from elsewhere would remain high. With new areas of global land mass opened up to fertile use by retreating permafrost and ice sheets, there is little reason to suspect that global food production will diminish.

    Comment by Ryan Stephenson — 12 Jul 2007 @ 8:09 AM

  97. Umm, Ryan, whilst the UK may well be able to afford to import food at will, many other countries cannot. As a related illustration, in Mexico they had riots due to the rising price of corn, which in turn was related to the increased use of corn in biofuels making a scarcity of it, which meant rising prices.

    Or in other words, in a world with reduced agricultural output, poor people will starve whilst the rich carry on eating. (And wasting)

    Comment by guthrie — 12 Jul 2007 @ 9:37 AM

  98. Why do people presume these vast areas can produce food in the quantities that will be needed?

    The sun is not going to alter its ways to save our bacon.

    Comment by J.C.H — 12 Jul 2007 @ 9:49 AM

  99. RE: #87

    Hey James;

    I guess that I was trying to address the mechanisms of the GHG theory rather then address the AGW Carbon Dioxide concentrations. I am not denying that CO2 is higher or that the models are portraying relationships correctly. What I am trying to understand is the natural science mechanisms involved.

    I also have difficulty in understanding how approximately 2.6 watts/meter^2 (Hansen et al 2005 suggested @1.85, I have seen estimated values between 1.46 and 6.4, the most recent was 2.64) in the 1.8 � 3.2 um range is increasing the average localized surface temperatures 0.5Deg C. Especially in light of the balance of solar insolation in the roughly 250 nm to 25um centered around the 550um frequency, at about 850 to 1200 watts/meter^2 for 9-16 hours per day. If I calculate the amount of daily energy, I have approximately 0.9% of the daily radiant energy coming from the CO2, if I understand this correctly. Based on 850 watts / 8 hours /day, I am seeing that it takes about 23.2 watts/meter^2/deg to raise the earths surface temperature to about 293 Deg. K (excluding any geothermic heat sources). Based on this rough calculation, I am seeing that the increased CO2 sourced radiant energy should be responsible for about a 0.1 Deg increase, at this energy level.

    In essence, I do not understand how the presence of CO2 is increasing my localized temperature average around 0.5 deg C. If the issue were that this extra energy was resident in the atmosphere longer and it takes 8-12 hours to release 6800 watts of energy /meter^2 in a clear night sky then the 62 watts associated with the radiant CO2 induced long wave temperature should only require about 4 min. I have done a lot of research on .gov and .edu sites, it appears that eventually most of the added energy does escape the atmosphere eventually.

    This only goes to suggest to me that the issue of AGW is not direct radiant warming; but, changes in large scale weather patterns. The localized temperature average does not appear to be increasing because of added radiant energy; but, because of changes in Jet Stream flows, stagnant weather fronts and possible changes in cloud characteristics. I guess my big question is, does anyone have any publicly available references as to how the increased atmospheric temperatures are affecting these large weather patterns?

    I do not argue that the models of today have amazing capabilities; however, a mathematical construct is not helping me understand the natural mechanisms involved. It helps me with my understanding when I can couple the source and the effect. At least it helps me understand why my garden does not get enough rain or whether I should go to the effort�

    (A little off topic, I recently saw a NASA article on the Earth�s Observatory site: http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17698 about the warming of the upper troposphere and the cooling of the stratosphere demonstrated by satellite tracking. Has anyone seen any C14 measurements in this region? I am curious if this is actually due to the increase in CO2, which Dr. Georg Hoffman may have suggested in Ukweatherworld, is concentrated in the lower troposphere based on direct measurements, or an increase in UV due to stratospheric Ozone reduction. (I figure if the Dobson Units correlate and there is an increase of C14 in the region this might help with the validation.) As to anomalies, the CloudSat and CALIPSO LIDAR experimental packages have demonstrated increased water vapor intrusion in the Polar stratospheric regions and a correlation here may help as well.)

    Again thanks James, my apologies if there is a miscommunication, my primary concern is to try to understand the specific mechanism of regional or localized warming not necessarily global warming. Direct insolation radiative measurements either here at my house or in the ARM.gov SKYRAD/GNDRAD databases are not helping. An understanding of the mechanisms of the reduction in the range of daily temperatures and changes in weather patterns and their causes will.

    Dave Cooke

    Comment by L. David Cooke — 12 Jul 2007 @ 9:51 AM

  100. “Empirical evidence” seems to be the last refuge of the naysayers.There are many papers that have been written that show empirically that global warming is indeed attributable to human greenhouse activities. One by Stott, Stone and Allen titled Human Contribution to the European Heatwave of 2003.” Nature 432(Dec 2,2004). This study gives a statistical analysis that the European heat wave of 2003 has a small probablilty to have been a cause of natural variability alone, and most likely human activity bears responsibility for a component of this anomaly. Borehole evidence, of which there are plenty, show that surface warming caused by increased greenhouse gases is reaching to deeper levels. Models are able to best match the existing record when both natural and anthropogenic factors are included.
    There will always be uncertainties. Science has never been 100 percent sure. This is what science is about.Karl Popper made references to it being characterized by its disprovability. Waiting for bullet proof evidence of human induced warming before taking any action would be like waiting for your house to burn down before buying fire insurance.
    As far the word theory is concerned. When applied to science it is not speculation or a hunch. A scientific theory is an explanation of world phenomena that are supported by data, analysis, and coherent conclusions and can be rejected when evidence contradicts this explanation. The theory doesn’t have to describe all aspects of the phenomenon. Just because climatologists don’t know every aspect of Earth’s very complex climate system doesn’t disprove the greenhouse theory.

    Comment by Lawrence Brown — 12 Jul 2007 @ 10:16 AM

  101. #96

    I visit the UK regularly, as my wife is from Yorkshire, and I would indeed be surprised if the UK’s own agriculture would be much negatively affected soon, and you may even get to have vineyards in Scotland, a fine thing, I’m sure, to replace the losses of vineyards in Spain & Italy. You may have to deal with insects that aren’t currently bothersome.

    A) Agricultural production depends not only on temperature but on water and soil quality.

    For North America:
    a) Do you think you know enough about soil quality in Canada AND
    b) Enough about likely future rain patterns

    to be *sure* that food production will not diminish as crops like wheat shift from US to Canada?

    Take a look at the chart at end of:

    http://news.bbc.co.uk/2/hi/science/nature/6200114.stm

    Unlike UK agriculture, some places in the world really have to worry about water; California (which grows half the fruit & vegetables in US) has state planners seriously worried about global warming’s effects on agriculture here. The US West, in particular, is strongly dependent on snowmelt patterns, as is much of South & East Asia.

    Likewise:
    The “Green Revolution” saved India & China from starvation. I’m sure they’ll be quite happy to get wheat from Mongolia and Siberia.

    Do you know enough about the soil & rain conditions in Russia to be sure all is well?

    B) The world currently supports a global market in food, at least for developed countries. This depends on cheap energy. Oops. The further food has to travel, the more expensive it’s going to get. Of course, a lot of very productive agriculture depends on serious energy inputs.

    C) And finally, how are UK fisheries doing?

    None of this says: “the world is doomed”, but blithely writing this off as a problem is *not* what people are doing who actually are involved in food production.

    Comment by John Mashey — 12 Jul 2007 @ 10:33 AM

  102. RE: #99

    Hey All;

    My apologies to the purists in the prior post, I had not converted to Joules or watts/meter/sec/sec in my calculations. Basically this involved a ratio and since both values were in the same form a direct ratio without the conversion should be fine. Granted my values might be more in question; however, it certainly helped me in understanding what I was trying to share. (Though it might be an impediment to others…)

    Thanks Dave

    Comment by L. David Cooke — 12 Jul 2007 @ 10:50 AM

  103. Dave, greenhouse gases intercept the infrared photons. Greenhouse gases emit infrared in any random direction once they’ve absorbed infrared; in addition they bump and grind, and transfer the energy to other molecules.

    The only energy outbound is the infrared photons that don’t interact again, that go directly out into space.

    Do you understand the “mean free path” number, and how that controls the rate at which energy moves off the planet from the atmosphere? You seem to be stuck on the old, frequently asserted, frequently explained notion that all the radiant energy could just zoom out into space somehow. If it could, the infrared astronomy people wouldn’t be building all those satellites —- the sky is _bright_ in the infrared, our atmosphere _glows_ in the infrared and half that heat is pointed downward on average.

    Comment by Hank Roberts — 12 Jul 2007 @ 10:58 AM

  104. Oh, and, dang, this is entirely off topic. As Ray and others remind us, RC is not a climate chat room. Pointer, hosts, please, to where the recycling of the fundamental questions frequently repeated should happen. Maybe at Stoat? Dano’s “How To …” page?

    Comment by Hank Roberts — 12 Jul 2007 @ 11:00 AM

  105. I think Dave Cooke just summed up my problem, the models have amazing capabilities but they do not help me understand. I listed the main points that I have problems I have accepting the CO2 Theory yet I have not seen anyone point me to a study that uses empirical data to explain these issues. If the proxy record is not correct, then how do we know current warming is unusual? Since there has never in the past been a time when CO2 has driven warming or cooling, how do we know the climate sensitivity is that high? If the sensitivity is low, then adding CO2 will have little impact. Can any one here provide something other than a model to show what is really happening?

    I realize my support for a Theory in the scientific community means nothing, but since this is being used to drive economic and political change I think it does. So, please show how this Theory address the question I have asked, with empirical studies, and I will support it, if not, accept that the theory is not correct yet and find out why the climate is getting warmer.

    [Response: Your conclusions are based upon fundamentally flawed premises. i) we do not think GW is caused by greenhouse gas increases simply because current changes are unusual, ii) there are plenty of times in the past when CO2 has driven warming - the PETM, the Quaternary ice ages as a whole, the Cretaceous, etc. iii) there are multiple ways to determine climate sensitivity: http://www.realclimate.org/index.php/archives/2006/03/climate-sensitivity-plus-a-change/ - and they all give pretty much the same answer. - gavin]

    Comment by Vernon — 12 Jul 2007 @ 11:08 AM

  106. “Umm, Ryan, whilst the UK may well be able to afford to import food at will, many other countries cannot. As a related illustration, in Mexico they had riots due to the rising price of corn, which in turn was related to the increased use of corn in biofuels”

    Supreme irony don’t you think? Riots caused by proponents of AGW telling us to use less fossil fuel so we burn Mexcian food sources to allow us to use our cars. Maybe it would have been better if we had let them eat and not made a big thing about AGW… (you could also have a word with the Mexicans about fecundity).

    Or in other words, in a world with reduced agricultural output, poor people will starve whilst the rich carry on eating. (And wasting)

    Comment by Ryan Stephenson — 12 Jul 2007 @ 11:32 AM

  107. RE #106 and biofueld v. food. As a person concerned about AGW, I have never been an advocate of biofuels from food crops (though they are fine from cow dung and other agri waste). In fact when you extract gas from cow & human dung, I read that the left over product is even a better fertilizer than if gas had not been extracted from it.

    There are 100s of ways to reduce our energy consumption without lowering our living standards or fun in life. It just takes a little thoughtfulness and a big heart. And when the plug-in hybrids come out, I plan to get one so I can do 95%+ of my driving on my wind-powered Green Mountain electricity.

    We don’t have to take food out of starving people’s mouths to run our SUVs coast to coast in pursuit of some illusory happiness.

    Comment by Lynn Vincentnathan — 12 Jul 2007 @ 1:34 PM

  108. Vernon.

    Completely independently of the past climate records, one expects GHGs to warm the Earth based on what we know about radiative transfer and spectroscopy. In fact speculation that increased CO2 levels would warn the Earth was first made about a century ago….long before the current warming or any of the paleoclimate data.

    See

    http://www.aip.org/history/climate/index.html

    http://www.realclimate.org/index.php/archives/2007/04/learning-from-a-simple-model/

    http://www.realclimate.org/index.php/archives/2007/05/start-here/

    and…

    http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument/

    Comment by David donovan — 12 Jul 2007 @ 1:40 PM

  109. I will be focusing on Greenland and perhaps more widely the cryosphere in later posts, but as some of our participants are focused on the effects of climate change upon England, the following might be of value to them…

    A quick note regarding the UK:

    I would strongly recommend checking out the Met Office Hadley Centre – a world class climate modeling center in the UK. They have some projections specific to the UK.

    Here is their website:

    Met Office: Climate Change (Hadley Centre)
    http://www.metoffice.gov.uk/research/hadleycentre/index.html

    Here is one of their non-tech documents:

    New scenarios of UK Climate Change (UKCIPnext)
    IRCCCG, 17 October 2005
    http://www.ukcip.org.uk/scenarios/ukcip08/documents/UKCIPnext_powerpoint.pdf

    A few of the projections they make:

    1. The likelihood of 2003-type European summers has already doubled and may be the norm by 2040
    2. Precipitation will increase roughly by 30% during the winter by the 2080s
    3. Summers will be drier by roughly 30% by the 2080s
    4. Storm surge will increase by roughly a meter by the 2080s
    5. Current emissions will have little effect upon what happens on land until 2040 after which there will be increasing divergence

    Comment by Timothy Chase — 12 Jul 2007 @ 1:43 PM

  110. Ryan

    I love the way you seem to refer to AGW in the past tense.

    Comment by Hugh — 12 Jul 2007 @ 1:51 PM

  111. RE #86, Heather, I’m a greenie & proud of it, but don’t have time to follow your links or the live earth concert (tho I vaguely heard about it & some criticism that the travel involved GHG emissions).

    My opinion would be that anything to inspire people to do the right thing would be good, even if there’s some upfront GHG emissions, as long as there’s net reductions. Like sometimes it takes GHG emissions to reduce GHG emissions overall.

    And I’m thinking that if all the “brownies” out there (not to be confused with Girl Scouts) would have started doing the EC (ecologically correct) things like the greenies did 17 or more years ago when everyone really should have started reducing their GHGs, then I guess they wouldn’t need to have live earth concerts to inspire people to do so now. So, perhaps the brownies are to blame, not the greenies.

    For instance, when I became aware of AGW in the late 80s, early 90s I reduced my GHG emissions by about 1/3 or more, and thought all I had to do was tell other people about AGW & how much I was saving by reducing GHGs, and then get back to my regularly scheduled life. Instead it’s been a VEEERRRRY long haul. I just hope the concert has some effect, and changes some hearts and minds, but my experience tells me the brownies are just getting worse, not better.

    Comment by Lynn Vincentnathan — 12 Jul 2007 @ 1:59 PM

  112. Re 96 Ryan Stephenson: “Well the last 60 years of “global warming” certainly hasn’t. I would be more worried about mad cow disease – to keep things in some sort of perspective….
    However, there is little chance of glabal warming being a problem for food supplies in the UK.”

    Perhaps not in the UK, but much of Southeast Asia is already nearing the heat stress upper limit for rice, regardless of how much water is and will be available as the Himalayan glaciers recede. Australia’s western grain district has been devastated by the current ongoing drought. The southwestern US is also in long-term drought, and the Colorado River reservoirs–source of much of the agricultural irrigation water for the region–are down alarmingly. World fisheries are all in decline, many having already collapsed.

    GW does not bode well for the UK’s 40% imports.

    Comment by Jim Eager — 12 Jul 2007 @ 2:30 PM

  113. RE: #103

    Hey Hank;

    Actually, I feel very comfortable with a radiation path value or as you call it a “mean free path number”, it should describe emission rate from the earths surface into space. I also am familiar with the inherent infra-red signature of the earth and its atmosphere in the 15-20um band (excluding the additional radiation load from increased atmospheric CO2).

    I was responding to James’s statement that temperature was not the significant factor from increasing CO2 instead it was long wave radiation. I have not seen an earth surface radiation increase signature in the arm.gov SKYRAD databases, nor a regional long term daily temperature mean increase.

    In essence, locally, over the past 27 years, at most I have seen more indicators of wide scale drier air masses and less precipitation. Based on the news, it appears that it is not necessarily that there is less precipitation globally, only that the precipitation appears to be more regionally concentrated.

    I was simply suggesting that the additional radiant energy must be retained in the atmosphere and must be affecting the large scale weather patterns, as the increase of 0.009% in the CO2 sources radiant energy does not appear to explain a global daily temperature range compression or an approximate daily mean increase of 0.5 to 0.8 Deg. However, stagnant air masses and a lack of the influence of the sub-tropical Jet Stream moving northward during the Summer Season here in the NH, does help explain the increase in temperatures and the reduction in precipitation.

    In essence, it appears that the Summer Seasonal sub-tropical Jet Stream appears to be less active apparently resulting in more stagnant barometric pressure waves between 25 and 35 Degrees. Hence, I was asking if James or anyone else might be aware of any studies demonstrating this mechanism or an interpretation of this mechanism. I seem to remember a study about 2 years ago wrt changes in the Walker Circulation. I remain curious if there had been any follow up or any new work in regards to either the ENSO or NAO and the energy input from CO2.

    My apologies if the search for this data appears to have ruffled your feathers; however, based on the specifics I was looking for and my failure to find them, along with the lack of recent periodicals misquoting science professionals, it is now apparent that this remains an opportunity for further research. By the same token, apparently the NASA reference I had included in my post, looking for more data, apparently remains out side of the current state of the knowledge of climate science…

    Believe me Hank, I respect the resource, if I want to blog, I play elsewhere… Your reaction told me much!

    Dave Cooke

    Comment by L. David Cooke — 12 Jul 2007 @ 2:30 PM

  114. Re 101 John Mashey: “For North America:
    a) Do you think you know enough about soil quality in Canada AND
    b) Enough about likely future rain patterns
    to be *sure* that food production will not diminish as crops like wheat shift from US to Canada?
    Take a look at the chart at end of:”
    http://news.bbc.co.uk/2/hi/science/nature/6200114.stm

    I’ve deflated this one before.
    1) The blue shaded are is less than half the size of the yellow shaded area.
    2) Much of the eastern third of the blue area is Canadian Shield, some of the oldest exposed bedrock on Earth.
    3) The western sixth is the Canadian Rockies, the next sixth is watered by them, and the glaciers that feed the rivers are shrinking.
    4) The upper half has plenty of water, but it is presently boreal forest and muskeg.

    Lots of luck feeding North America from what remains, let alone exporting food.

    Comment by Jim Eager — 12 Jul 2007 @ 2:41 PM

  115. Dave, I’m just another reader, so don’t mistake _my_ ignorance for the current state of the knowledge of climatologists! More like the measure of ignorance of well meaning, too busy, and mathematically limited readers (grin). I recall mentions that we should expect more precipitation, not less, but “local variability” rules, and likely more intense precipitation when it happens. The soil erosion folks are looking at the erosion at the end of the last ice age for examples, and some are scary looking.

    Comment by Hank Roberts — 12 Jul 2007 @ 3:03 PM

  116. re: #114 Jim Eager:
    I’m not sure I understand your post: I thought I was pretty clear that I did not support Ryan’s “don’t worry.” I picked the map because it was from the UK & obvious that the change would substantially lessen the area for an important crop, even if water and soil conditions were equal (which is unclear or unlikely).

    If anyone else thought I was saying “don’t worry”, I’m sorry for any ambiguity. I’m an old farmboy, I’ve visited Canada dozens of times, I’m up there 2-3 times/year, and there’s no way I can think of that higher temperatures & likely rainfall patterns improve North American food production overall. I know how much CA worries about effects on agriculture, and better grapes in the Okanagan will not compensate for the loss in Napa+Sonoma.

    Comment by John Mashey — 12 Jul 2007 @ 3:46 PM

  117. re: #114 Jim Eager:
    I’m not sure I understand your post: I thought I was pretty clear that I did not think that the blue piece was likely to replace the yellow piece, even if water and soil were fine.

    Did anybody else read #101 and think I was supporting Ryan’s “don’t worry?”

    If so, I’m sorry for any ambiguity. I’m an old farmboy, I visit Canada ~3 times/year, and there’s no way I can think of that higher temperatures & likely rainfall patterns improve North American food production overall.

    Comment by John Mashey — 12 Jul 2007 @ 3:54 PM

  118. RE: 115

    Hey Hank;

    Thanks! I appreciate your basis…, grining back!

    I had been trying to run down the soil erosion and precipitation as part and parcel of the carbon sink question, John Mason at UKweatherworld has been helpful there. I was hoping to put together a quick post there to address Vernon’s questions.

    I am afraid Vernon and I are not necessarily alone. We have the background; but, cannot convert the “knowledge of what” to the “mechanics of how”, the radiative model (sensitivity), recommended is not helping much. Contrary to Lawrence’s suggestions, the empirical is not a bastion; but, a conveyance, for those of us that may be more limited… David’s additions have been welcome; but, not necessarily in line with the need. The problems may resolve themselves as the regional empirical evidence may change in the next few years, as the model grid resolutions improve (RC’s 27 May Talking Point.)

    Dave

    Comment by L. David Cooke — 12 Jul 2007 @ 3:55 PM

  119. Re 109:
    Timothy Chase says in part:
    “I would strongly recommend checking out the Met Office Hadley Centre – a world class climate modeling center in the UK. They have some projections specific to the UK.

    Here is their website:”

    Met Office: Climate Change (Hadley Centre)
    http://www.metoffice.gov.uk/research/hadleycentre/index.html

    Amen to that.
    This is an excellent source. Though what they say about the Greenland Ice Sheet seems optimistic. Here’s what they said in June 2006 about the Greenland Ice Sheet: ” In the case of the Greenland Ice Sheet,if summer regional temperatures were to rise by about 3C,the ice sheet would begin to reduce in size.It would be slow to disappear, perhaps half of it taking about 1000 years to melt.This critical temperature is predicted to be reached by the end of the centuryby most combinations of climate models and future emissions scenarios.”
    Here’s the URL http://www.metoffice.gov.uk/research/hadleycentre/pubs/brochures/2005/clim_green/slide56.pdf

    Comment by Lawrence Brown — 12 Jul 2007 @ 4:15 PM

  120. Re: #116/117 John Mashey: “I’m not sure I understand your post: I thought I was pretty clear that I did not think that the blue piece was likely to replace the yellow piece, even if water and soil were fine.”

    You were perfectly clear, John, I was just trying to emphasize the point to Ryan that the impact of a warmer climate on food production will not likely be a positive one in much of the world.
    Sorry for my own ambiguity.

    Comment by Jim Eager — 12 Jul 2007 @ 5:31 PM

  121. As Ray and others remind us, RC is not a climate chat room.
    -Hank Roberts

    Is there a site, of the caliber of RC, where people discuss meteorological trends, phenomenon and theories that can be recommended?

    Comment by catman306 — 12 Jul 2007 @ 6:32 PM

  122. Re 113: [I was responding to James's statement that temperature was not the significant factor from increasing CO2 instead it was long wave radiation.]

    If you’re referring to my comment #87, I think you misunderstood what I was trying to say. It’s not that temperature increases aren’t a significant result of increasing CO2. I was trying to make a point about how AGW theory developed. It’s not the case that people observed increasing temperatures and looked around to find some reason for the increase. Instead, the increase was predicted on theoretical grounds. Knowing how CO2 interacts with radiation, it’s possible to predict the temperature changes that will result from a particular change in CO2 levels. (This is complicated by feedbacks and so on, which is why you need computer models to compute it.)

    So we have this theory, and measurements show increases in CO2 level. Run everything through the computer model, and you get a predicted temperature increase. Now you look at actual measured temperatures and see if they agree with what was predicted to date. If they do, that increases your confidence in the models’ predictions going forward.

    Comment by James — 12 Jul 2007 @ 7:25 PM

  123. Pointer off-topic for Dave Cooke, this is very cautionary:
    Abrupt increase in seasonal extreme precipitation at the Paleocene …
    http://ic.ucsc.edu/~jzachos/eart120/readings/Schmitz_Puljate_07.pdf

    Comment by Hank Roberts — 12 Jul 2007 @ 8:06 PM

  124. From post #99
    “Especially in light of the balance of solar insolation in the roughly 250 nm to 25um centered around the 550um frequency, at about 850 to 1200 watts/meter^2 for 9-16 hours per day. If I calculate the amount of daily energy, I have approximately 0.9% of the daily radiant energy coming from the CO2, if I understand this correctly. Based on 850 watts / 8 hours /day, I am seeing that it takes about 23.2 watts/meter^2/deg to raise the earths surface temperature to about 293 Deg. K (excluding any geothermic heat sources). Based on this rough calculation, I am seeing that the increased CO2 sourced radiant energy should be responsible for about a 0.1 Deg increase, at this energy level.”

    The problem with this ‘rough calculation’ is that it is based on totally false data!
    The average insolation is 342 W/m^2 of which 77 W/m^2 is reflected from clouds and 30 W/m^2 is reflected from the surface plus 67 W/m^2 leaving 168 W/m^2 reaching the surface.
    See J. T. Kiehl and Kevin E. Trenberth, Bulletin of the American Meteorological Society, Vol. 78, No. 2, February 1997. I suggest you recalculate with more reasonable numbers

    Comment by Phil. Felton — 12 Jul 2007 @ 8:10 PM

  125. Gavin raised the issue of climate sensitivity to CO2 during the paleoclimate in the response to post #105.

    My math shows about 1.0C of warming per 2XCO2 (or at least very close to the low end of the range of 1.5C of warming per doubling.)

    For example, the following shows the estimates of CO2 concentrations in the atmosphere during the Phanerozoic (the last 540 million years.) [I use Berner's estimates here, the yellow line, since he seems to have the most credibility on this issue.]

    CO2 levels were as high as 2,000 ppm, 150 million years ago; 4,000 ppm, 400 million years ago and 7,000 ppm, 500 million years ago.

    http://www.globalwarmingart.com/wiki/Image:Phanerozoic_Carbon_Dioxide_png

    The temperature estimates in the palaeoclimate, however, are only about 2.0C warmer for 150 million years ago (3 doublings of CO2 from the natural level of 280 ppm), 5.5C warmer for 400 million years ago (4 doublings) and 6.0C warmer for 500 million years ago (nearly 5 doublings).

    http://upload.wikimedia.org/wikipedia/commons/thumb/f/f5/All_palaeotemps.png/800px-All_palaeotemps.png

    The Eocene Optimum is clearly a special case with temperature estimates of 6.0C warmer with a range of estimates for CO2 of 500 ppm to 3,000 ppm

    Comment by John Wegner — 12 Jul 2007 @ 8:28 PM

  126. Rate of change, John.

    Comment by Hank Roberts — 12 Jul 2007 @ 8:33 PM

  127. RE: #122

    Hey James;

    Thanks, actually that does help in my understanding of what you were trying to express.

    What I was trying to share is that in my goal to understand the mechanics of the GW theory, I do not see the earth surface measurement of CO2 radiant spectrum energy during a clear night sky in the SKYRAD database. Hence, I was trying to consider if it might be possible that the energy was “trapped” in the atmosphere and causing weather changes resulting in increased mean temperatures rather the actually heating the earths surface.

    Dave Cooke

    Comment by L. David Cooke — 12 Jul 2007 @ 8:45 PM

  128. RE: #123

    Hey Hank;

    If it is okay, I would like to share this with Andre and John on UKww, I am curious if this might have something to do with an uplift we have been discussing… I also want to look at it more indepth as well to see if how they have characterized the sedimentation in this region.

    Thanks
    Dave

    Comment by L. David Cooke — 12 Jul 2007 @ 8:50 PM

  129. RE: #101 Mr. Mashey, #114 Mr. Eager:

    Your timely comments about growing conditions resonate with my annoyance over the recent ‘rising CO2 will be a good thing’ jaunt by Bertrand, Prevost, et al., where they go from this statement: “The authors grew well watered and fertilized alfalfa” to this conclusion: “as the environmental transformation that is currently underway automatically insures that there will be a “greening of the earth” throughout natural and agro-ecosystems alike.”

    Assuming ample water, fertilizer, and non-stressful temperature conditions seems to me to leap over the probability of chaotic growing conditions associated with an AGW world. Not to mention that their report doesn’t state whether they subjected the specimens to the multiple cuttings typical of alfalfa production, address heat stress issues or the conditions’ concurrent effect on 4C weeds, or discuss the usual planting/seedling growth issues from unsettled weather conditions. Considering their experiment’s scope, that last quoted phrase strikes me as somewhere between a political statement and quite a leap in logic.

    Comment by ghost — 12 Jul 2007 @ 8:58 PM

  130. RE:#124

    Hey Phil;

    Actually, I am looking at specific numbers in watts per meter squared on the arm.gov data base for April the 13th 2007 on Nauru Island at the TWP SKYRAD daily insolation long wave detector. The Peak during the Spring Equinox there averages 1200 watts for nearly two hours with an average of 850 watts or above for a min. 8 hours with a rapid slope from 50 to 500 watts both preceding and succeeding the peak levels. (Except in the case of excessive cloud cover in which the value will be no less then an average of 500 Watts/meter^2 for most days for a minimum of 4 hours.)

    I am sorry if I have used a value you question. However, the value I have used is a direct observation with a known accuracy of around +/- 5 watts, based on the last quality check I noted.

    Based on my best understanding the insolative value at most ARM.gov sites supports a minimum of 850 watts/meter^2 of peak long wave incoming energy from sites ranging from about 53 Degrees N to around 23 Degrees S. during
    most days from mid spring to mid fall here in the NH. (This happens to be the peak solar insolative period and most likely to “charge” the atmospheric resident CO2.) I will have to go back and find the minimum long wave value; however, as my memory serves me it was not less that about 500 Watts/meter^2 in the Western Plains site. I am not sure; but, I believe the Alaska site may get down to a 300 watt region peak during the winter here in the NH.

    Maybe I am misunderstanding you, are you saying that the 324 watts/meter^2 is considered the 360 degree average global input? Such that you are comparing a globally averaged solar input against a modeled 24 hour CO2 radiant down welling input. Meaning, that you are saying that 0.8% of the 24 hour average radiant down welling energy is equal to the CO2 source. And this would be different from me saying that 850 watts for 8 of 24 hours means a total of say the solar 6800 watt hours/meter^2 as opposed to CO2 62.4 watt hours/meter^2 per day, resulting in about 0.9% of the long wave down welling energy being due to CO2.

    Could you please assist me in understanding your point. I apologize if I was not absolutely correct in how I approached the rough approximation; however, the values are fairly close. The only real difference is that I am allowing for my calculations to more closely follow the actual inputs and outputs rather then theoretical.

    If we wanted to be more accurate yes, you are correct we would have to express the specific surface detectable daily solar gains and distribute them then compare that to the distributed CO2 radiant gains. I am afraid all I have done was to demonstrate my apparent ignorance, my apologies.

    Dave Cooke

    Comment by L. David Cooke — 12 Jul 2007 @ 9:33 PM

  131. Dave, if you are asking about porting the digression somewhere, or permission for quoting or linking, I guess you’d want to ask the Contributors (contact info is behind the “About” link, top of page). I’m just another reader; I’ll follow pointers if you leave’em.

    Comment by Hank Roberts — 12 Jul 2007 @ 10:09 PM

  132. Re 129 “Assuming ample water, fertilizer, and non-stressful temperature conditions seems to me to leap over the probability of chaotic growing conditions associated with an AGW world..”

    Not to mention also the possible effects that CO2-stimulated growth could have on plant protein levels, carbon/nitrogen ratios, and differential responses by plants carrying out C3 vs. C4 photosynthesis, all of which could alter the productivity of crops and grasslands, the invasiveness of weeds, and food quality for grazers.
    Ref: Ehrlinger, J.R. et al. (2002) Atmospheric CO2 as a global change driver influencing plant-animal interactions.
    Integrative and Comparative Biology 42:424-430.

    Comment by Chuck Booth — 12 Jul 2007 @ 10:50 PM

  133. Fear not, giant veggies will feed the world:

    http://seattlepi.nwsource.com/getaways/091996/vege19_top.html

    Comment by J.C.H — 13 Jul 2007 @ 12:26 AM

  134. I’m not sure where to put this.
    Last night our national broadcaster (the Australian Broadcasting Corporation, ABC) showed the Great Global Warming Swindle (GGWS):
    http://www.abc.net.au/tv/swindle/
    It was followed by an interview of director Martin Durkin and a panel debate that included 3 vehement sceptics out of a total of 8 panelists.
    http://www.abc.net.au/tv/swindle/panel.htm
    The main sceptic with “relevant” expertise was Bob Carter (an environmental geologist), who was ably countered by David Karoly. Journalist Michael Duffy and Lavoisier Group secretary Ray Evans were also on the panel.

    It has generated huge debate:
    http://www2b.abc.net.au/tmb/Client/MessageList.aspx?b=89&t=1&a=0&te=False&ps=20
    http://www.abc.net.au/news/stories/2007/07/12/1976998.htm

    There were several in the audience who made bizarre statements during question time (eg. the eugenics roots of environmentalism) and online pre-show polling may well have been influenced by them (49.5% did not think human activity was a significant contributor to global warming).

    There was a mention of Lyndon LaRouche’s name and the group may have been the Citizens Electoral Council who venerate LaRouche:
    http://cecaust.com.au/
    http://cecaust.com.au/main.asp?sub=info&id=aboutlhl.htm
    They were clearly trying to motivate members prior to the show:
    http://www.cecaust.com.au/main.asp?sub=global_warming&id=ABC.html

    Comment by Bruce Tabor — 13 Jul 2007 @ 2:47 AM

  135. re 407 John

    Thanks for the link… quite astonishing. Seems the new game is to cut climate scientists from their data sources:
    _ Ground measurment gets trashed by a few pics circulating on the net;
    _ Satellite data is gonna lack because NASA’s directive board decided it was more important to go back to the moon.

    Hope Nasa’s move is not conscious (looking at last Micheal Griffin’s words about GW, I wonder…).
    We’ve got a nice expression in my country to call this: the ostrich policy (when facing a problem, hide your head in the sand and wait for it to go away…)

    Maybe off the scientific topic, but I’ve got a question for our excellent contributors here. Is climate science communauty gonna protest about this? Make some sort of official statment to the NASA directive board, through the IPCC for exemple?

    Comment by nicolas L. — 13 Jul 2007 @ 3:06 AM

  136. Sorry for being a little late for replying to Ryans comments #96 (of which much has already been said!).

    Since I also live in the UK, I’m seeing farmers waterlogged fields, with the high chnace of a ruined crop, as well as the continuing problem of large part of East Anglia becoming increasingly arid. Soil erosion continues to be a problem, and the mixture of wet mild winters and increasingly hot summers will increase pest damage, etc. Agricultural land in the UK will decrease under pressure from development, such as housebuilding. Lets not even talk about fishing.

    Importing food from the US? The latest IPCC report makes it clear that North American food production (as has already been mentioned) will fall as tempertures rise (after a small initial lift), and I suspect that European farmers as a whole will have much the same problems as the UK, with tempertures perhaps even higher in the South.

    Water stress will lower rice yields in SE Asia, and increased chances of flooding in certain areas of the Indian sub-continent will reduce the amount of land available for crops, and shortages will increase prices.

    China will also suffer problems with food scurity and water stress, and Africa will probably have even more problems feeding itself (and those cute little trays of veg in Tesco’s flown in from Kenya, etc will possibly disappear as oil prices rise anyway).

    As for London, the Thames barrier was build to protect the captial against storm surges, etc such as the one in 1953, which caused so much damage in both eastern England and in Holland. Climate change and the continuing sinking of southern Britain will increase the chances of another disaster, even with the Thames barrier. Dungeness power station is already under threat from the sea, with a constant effort to replemish the gravel banks that protect it.

    Of course we may get the fabled grapes as far as York, which at least means we will have some wine on hand – because I suspect that given the projections of climate change, we are all going to need a good stiff drink…

    Comment by MikeB — 13 Jul 2007 @ 3:20 AM

  137. re #105 Regarding the eemian interglacial. It has been suggested that this period was around 2 C warmer than today due to the higher sun in the northern hemisphere and not CO2 levels which I believe were similar than todays ?

    it is true though that climate simulations of that era cannnot produce the same temperatures as found in the paleoclimatic data without large simulated CO2 increases and that something appears to be missing from the simulations.

    This is mentioned in the book 6 degress by Mark Lynas. He claims that the reductionist nature of the models is to blame and that climate feedbacks of a systemic nature are more than likely the cause of the discrepency.

    Any truth in this ?

    Comment by pete best — 13 Jul 2007 @ 4:13 AM

  138. London rate of sinking into its own mud maybe as much as 100% faster than the rise of sea level:-

    http://news.bbc.co.uk/1/hi/sci/tech/6231334.stm

    Comment by Ryan Stephenson — 13 Jul 2007 @ 5:02 AM

  139. RE:#124

    Hey Phil;

    Oops, I forgot to include the reason I choose 850 as my median value. I used a simple RMS to Peak to Peak conversion 850 by 1.414 equated to around 1200 watts. The difference was around 350 watts. The min then would be approximately 500 watts which seemed to fit the application fairly well. That my value would equate to an average of 283 watt hours/ hour per day as opposed to calculated 324 watts you referenced may have been a little low. I leave it to you to suggest which may be a better approach. At least with mine I understand how it fits into direct measurements. I hope this helps…

    Dave Cooke

    Comment by L. David Cooke — 13 Jul 2007 @ 5:57 AM

  140. Oups, sorry guys… it appears the last message i posted found its way to the wrong thread: 135 here, though I was replying to a message in “No man is an (Urban Heat) Island”. Must have don’t some wrong somewhere when I was posting it.

    Can you fix it, or do I have to post it again in the right place?

    Sorry again

    Comment by nicolas L. — 13 Jul 2007 @ 5:59 AM

  141. Re: 134 and the Screening of the Global warming swindle show on Australia’s ABC.

    The audience for the panel discussion after the Swindle screening was hilarious. Besides the Larocheans there was at least one creationist. They threw it open to questions from the audience at the end only to discover that the place was stacked with incoherent loonies.

    As an antidote to the general silliness, there was a great interview on the ABCs Lateline show the next day with Carl Wunsch on what he thought of his involvement. He puts his points-of-view very well. You can see it here. Aaah, sanity and rationality. Well done Dr Wunsch.

    Comment by Craig Allen — 13 Jul 2007 @ 6:46 AM

  142. [[Based on my best understanding the insolative value at most ARM.gov sites supports a minimum of 850 watts/meter^2 of peak long wave incoming energy from sites ranging from about 53 Degrees N to around 23 Degrees S. during
    most days from mid spring to mid fall here in the NH. (This happens to be the peak solar insolative period and most likely to "charge" the atmospheric resident CO2.) I will have to go back and find the minimum long wave value; however, as my memory serves me it was not less that about 500 Watts/meter^2 in the Western Plains site. I am not sure; but, I believe the Alaska site may get down to a 300 watt region peak during the winter here in the NH.
    ]]

    You are confusing peak radiation received with average radiation received.

    The Solar constant at Earth’s orbit averages 1,367.6 Watts per square meter. But because the Earth is a sphere, half in darkness, and much tilted away from the source of illumination, the average insolation at the top of the atmosphere is only S / 4 or 341.9 W m-2. Another way to put it is: the Earth receives solar radiation on its cross-sectional area (π R2) but has an actual surface area four times this (4 π R2); thus the factor of 1/4.

    The amount that actually goes into the climate system is less still, since about 30% of Solar radiation is reflected back into space by clouds, atmosphere and ground (mostly clouds).

    Comment by Barton Paul Levenson — 13 Jul 2007 @ 7:00 AM

  143. Re #138 As the article Ryan references actually makes clear, London isn’t “sinking into its own mud”, at least as a whole (parts of it are sinking due to the abstraction of water, and settlement of Holocene deposits along the Thames); rather, Britain itself is tilting, with the north rising and the south sinking, in a rebound effect following the melting of glaciers at the end of the last ice age. The article gives values of 1-2mm/year for this process, and about 1mm for sea level rise (as measured by tide gauges). Sea-level rise may of course speed up over the next century, while the rebound will not. As someone else noted, the current rate of relative sea-level rise can be handled technologically using barriers and pumping (and if necessary we can call on Dutch expertise, as we did to drain the East Anglian fens some centuries ago!), but the technology is of course expensive.

    Comment by Nick Gotts — 13 Jul 2007 @ 8:58 AM

  144. Timothy

    RE 109 Perhaps you should tell the 30,000 people in the UK made homeless by flooding in the last few weeks that the Met Office are predicting 30% drier summers. I am sure it will make them very happy.

    Comment by Paul — 13 Jul 2007 @ 9:19 AM

  145. Re #141, #138 The ABC GGWS debate
    Hi Craig and others,
    The unusual audience comments/questions can perhaps be explained by this article on the LaRouche Youth Movement’s (LYM) US site. Interesting reading for us “warmers”. See:

    http://larouchepac.com/news/2007/07/12/australian-lym-raises-nazi-eugenics-roots-environmentalism.html

    ‘Australian LYM Raises the Nazi Eugenics Roots of Environmentalism
    July 12, 2007 (LPAC) At a live Australian Broadcasting Corporation debate on Global warming, with 15 Larouche activists present in the audience out of 80 attendees, the ALYM and Australian chapter members present got to ask 4 questions to the panelists, exposing the genocidal roots of environmental philosophy.

    The show was aired at 8:30pm, the two and a half hour broadcast on Australian TV started with a showing of the Global Warming Swindle documentary, then showed 2 interviews. The first was with the director of the documentary, Martin Durkin, in which he fended off attacks on his work. The other was with Karl Wunsch, the MIT oceanographer who has said that his contributions to the documentary were misquoted and misconstrued. After this, a live broadcast roundtable discussion was held with 5 “warmers” and 3 “skeptics.” Some notable panelists were Professor Bob Carter, (James Cook University), Australia’s most famous global warming skeptic, and Greg Bourne, CEO of the Australian branch of the World Wildlife Fund. The broadcast’s aim was to completely discredit the Global Warming Swindle documentary.

    It was at this live debate in the studio of ABC Sydney and broadcast on Australian national television that we intervened. Three organizers were kicked out on sight for “suspicion of being potentially disruptive,” while 15 activists, LYM and chapter members, made it in safely. Two of questions centered on the relationship between Nazi race science, eugenics, and environmentalism. One ALYM member, wearing a t-shirt that said “Anthropogenic Global Warming is a bigger fraud than your girlfriend’s orgasm!”, asked about statistical vs. dynamic analysis concerning the method in which the “warmers” gather their data. For the last question of the broadcast an organizer sharply asked if the panelists were for or against human populations. A more detailed report, including the reactions of the panelists to the questions, is forthcoming.

    The ALYM will stay in Sydney for a week in effort to force the Australian Government to investigate the BAE scandal. A full report on this campaign is also forthcoming.’

    Comment by Bruce Tabor — 13 Jul 2007 @ 9:25 AM

  146. RE #106 “Supreme irony don’t you think? Riots caused by proponents of AGW telling us to use less fossil fuel so we burn Mexcian food sources to allow us to use our cars. Maybe it would have been better if we had let them eat and not made a big thing about AGW… (you could also have a word with the Mexicans about fecundity).” – Ryan Stephenson

    This is something of a distortion. Campaigners on climate change issues have been warning for some time that biofuels are not a viable alternative to fossil fuels, because of the amounts of land required, and that in some cases there is little or no reduction in net GHG production (when coal is used in the extraction process), or even (when tropical forests cut down for oil palm plantations) a large increase. The increase in biofuel production in the US that has caused rising tortilla prices in Mexico is down to subsidies (about $6.5bn annually and growing, according to http://www.iisd.org/subsidies/gsi_nov_2006.htm). The Bushites have been promoting biofuels to subsidise US farmers and to reduce dependence on oil imports, not out of concern over GHG emissions – although they have recently started presenting the latter as an additional advantage. Incidentally, the annual growth rate of Mexico’s population has come down from 3.5% in 1965 to 1% in 2005, so it appears they may not need Ryan’s condescending “word about fecundity”.

    Comment by Nick Gotts — 13 Jul 2007 @ 9:32 AM

  147. Re #144 [RE 109 Perhaps you should tell the 30,000 people in the UK made homeless by flooding in the last few weeks that the Met Office are predicting 30% drier summers. I am sure it will make them very happy.]

    Why should it? Drier summers on average are quite compatible with more frequent flooding if rain, when it comes, does so in more concentrated bursts.

    Comment by Nick Gotts — 13 Jul 2007 @ 9:37 AM

  148. Re #86 Heather, I don’t agree “this man” (one Ken Liston) makes any interesting points. He makes the very obvious and oft-repeated point that globe-trotting celebrities appear hypocritical if they campaign for a reduction in greenhouse gas emissions while continuing their wasteful lifestyles. Because this is such an easy point for denialists to make, I doubt whether the overall effect of the “Live Earth” concerts was positive in terms of making action to reduce emissions more likely. However, the point has no relevance whatever to the causes of climate change – so there is no reason why it should have changed Liston’s opinion on anthropogenic climate change from “sceptical” to “very sceptical” as he claims it did. When someone says something as stupid as that, you know they are either a fool, or are making a false claim for rhetorical effect.

    Comment by Nick Gotts — 13 Jul 2007 @ 9:57 AM

  149. RE: #142

    Hey Barton;

    Thanks, I think I accounted for this, only I was looking at the data from an earth side detector. In essence, the amount of energy constant I calculated from ran at about 283 watts/meter^2 rather then either the 324 from Phil’s reference and the roughly 342 from your reference.

    My actual fallacy in my estimates, and my apologies to James, should be related to my error in suggesting that the radiative value would have been about 0.1 Deg in #99. I reviewed what I had done and found that if the references I have found subsequently are correct, the atmospheric heat content due to CO2 should be about 12% and the atmospheric heat content should be about 30-38 Deg. If this is correct then the atmospheric CO2 heat content should be about 4 Deg. with an increase of about 0.6 Deg down welling since about 1850 due to the additional 100ppm.

    The issue of the mechanism question appears to remain, for me… If this input is direct radiative energy, I have more research to do. If the warmth is actually driving large weather patterns then it makes more sense to me; but, again I have more research to do. However, my thanks for your input. (Note: I am trying to establish data at the point of perception, so that I can relate to it better.)

    Dave Cooke

    Comment by L. David Cooke — 13 Jul 2007 @ 10:59 AM

  150. Reading Kim Stanley Robinson’s FIFTY DEGREES BELOW, a novel. This second one in his trilogy about global warming is about the N. Atlantic ocean conveyor & downwelling stopping bec of fresh water from Arctic and Greenland ice melt. It talks about the eastern portion of N. America and much of Europe going into a deep freeze, tho Robinson’s rendition is more realistic than DAY AFTER TOMORROW.

    I believe this topic has been covered on this site, and I think the upshot was the experts said that even if the ocean conveyor slows greatly or stops (and I believe there ARE signs of it slowing), that the resulting cold would be offset somewhat by global warming (since we are at a high, interglacial plateau, not in an ice age valley at present), so it wouldn’t be so cold as to ruin agriculture. That the earlier shutdowns had occurred when the world was just coming out of deep ice ages, so the N. lat temps got a lot colder than they would today, and the resultant ice/snow albedo reinforced the reversions to ice ages.

    (Of course, none of this addresses just how hot it will get at my place in the Gulf of Mexico, bec the warm current has stalled in the south, and we won’t be getting as much cool water coming in — bec the muckity mucks live up north and not down here, I guess.)

    Anyway, let me know just how wrong I got this, and whether Robinson’s novel has any validity.

    Comment by Lynn Vincentnathan — 13 Jul 2007 @ 11:08 AM

  151. Lynn, Robinson does a good job on the politics; unfortunately he picked that particular scenario for the first book in his trilogy and the science has changed; a THC slowdown is discussed elsewhere here as likely at ‘worst’ to just slow down heat transport and somewhat reduce the rate of European warming rather than cause a cold event.

    I like Robinson’s books, just finished the third of that trilogy, and have heard him talk locally in SF. He’s making a real effort to understand both the science and the politics; the time line for writing books moves slower than the science news! In the real world, without the fictional sudden THC collapse, the variability of weather and storms and floods he described have rather much happened anyhow, although for other reasons. So has the obfuscation.

    Robinson has a presidential candidate get elected who understands science, after a failed attempt by the administration to steal the next election because some of their team have ethics and defect …. I dunno. We can hope.

    Comment by Hank Roberts — 13 Jul 2007 @ 12:09 PM

  152. Re 106 Ryan Stephenson: “Supreme irony don’t you think? Riots caused by proponents of AGW telling us to use less fossil fuel so we burn Mexcian food sources to allow us to use our cars.”

    More like supreme disingenuous and deliberate drive-by smear and mischaracterization on your part.

    The riots were sparked by the sharp increase in corn flour prices, caused by speculators taking advantage of the rising prices of corn stocks used to distill ethanol–from a completely different type of corn, btw.
    http://news.independent.co.uk/world/americas/article2697788.ece

    The surge in ethanol production is due to a Bush administration policy of subsidies to reduce US dependance on imported oil rather than any serious plan to reduce fossil carbon derived greenhouse gasses.

    Moreover, anyone who has seriously looked at biofuels, both ethanol and biodiesel derived from oil seed crops, will tell you that after input and production emissions and land use changes are factored in, biofuels are not at all a carbon neutral solution to AGW.

    You can apologize any time now.

    Comment by Jim Eager — 13 Jul 2007 @ 12:13 PM

  153. >Mexico
    Heard on the radio yesterday, in the context of the debate over immigration law: Corn that was grown by some 100,000 farmers in Mexico was forced off their market after NAFTA by loss of their tariffs, which led to their market being flooded with much cheaper corn grown in the USA with lots of government crop subsidies; those farms collapsed and those people are now looking for work.

    Tangles: The corn lobby in the USA is huge because of the government-subsidized corn market; corn is subsidized to keep the [economic term for medium exchange deleted to escape spam filter] lower on high fructose corn syrup; that is being used because of the longterm embargo on imports of sugar from Cuba and the tariffs on sugar from other American countries to protect the corn industry. As someone from the left spoke of the wheel put it, well I’ll be ADMned…. those from the right spoke blame it all on Fidel; those from the libertarian and larouchie spokes probably blame the loss of the [generic term for large establishments dedicated to the use of non-random operations to separate medium of exchange from patrons, term edited to escape filter] that were a major feature of Hemingway’s Cuba, but Nevada benefited when those business families moved their operations. You pays your money and you buys your votes. In Mexico and Canada, Coca-cola is made with real sugar from cane; cane sugar doesn’t raise men’s triglycerides the way the high fructose corn syrup does. Here’s to your health.

    But I digress. Sorry.

    What’s news from the Greenland ice cap studies this week, anyone? Anyone gotten hold of the scientists who’ve written the papers, to invite them to comment or expand further?

    Nice topic. Let’s use it.

    Comment by Hank Roberts — 13 Jul 2007 @ 2:46 PM

  154. Re: #79

    Dave,

    You and I agree that regional climate change is the holy grail of climate change knowledge. It is what needs to be understood much better, in order to facilitate prudent policy making.

    One thing that comes to my mind: because we do not completely understand all of the physics involved in distribution of heat from the tropics around the globe, we cannot state with certainty what the impact of a rising temperature will be. As you point out, it is not as simple as “CO2 builds up / the world gets hotter” or as Al Gore is fond of saying, “the planet has a fever”. Because (a) we don’t really know how bad that fever is, in the context of what the likely changes to regional climates will be, and (b) we don’t know what offsetting mechanisms may come into play in order to blunt the full impact of the CO2 increase. In other words, perhaps nature will respond in a way we have not previously observed and which nobody has yet hypothesized (or which somebody has hypothesized and been told they are a crackpot).

    However, I stuck to basics in my answer to Vernon. One thing we know for sure: sea levels will rise. There is the potential that they will rise rapidly when we pass a tipping point. We have seen, many times over, that once a sheet of ice becomes unstable it can disappear at a very rapid rate, i.e. days or weeks. I am fairly certain that this is Dr. Hansen’s primary concern, that there is such a tipping point and that we are close to locking it in.

    I can draw a pretty direct relationship between CO2 buildup and rising sea level. Not only does it exist in the historical record, we can test it and we can model it. I feel quite comfortable that the rapid demise of summer Artic ice cover is directly related to climatic conditions caused by a warming planet.

    I completely agree with you that we must pay much more attention to the specific atmospheric effects which rising temperatures can cause. As I said in my previous post, that answer is much more pertinent to each of us than the gradual rise of “global temperature.”

    Comment by Walt Bennett — 13 Jul 2007 @ 3:01 PM

  155. Re #152: [The riots were sparked by the sharp increase in corn flour prices...]

    Apologies for getting off topic, but I buy corn tortillas & corn meal fairly often. I don’t recall noticing any increase in price here in the US – certainly not a 400% rise – so it seems that there might be more to the story than greedy Americans putting Mexican tortillas in their gas tanks.

    Comment by James — 14 Jul 2007 @ 1:02 AM

  156. The wave-cut terraces on San Clemente Island shown in the photo on this page http://pubs.usgs.gov/fs/fs2-00/ illustrate sea level variation up to about 60 metres. The commentary suggests wave-cut terraces and beach deposits from regions as separate as the Caribbean and the North Slope of Alaska suggest higher sea levels. Have there been studies comparing the various wave-cut terraces around the world and do they correlate with various meltwater pulses? Is it possible to identify from a global wave-cut-terrace correlation how different ice sheets might participate in the overall disintegration dynamics, or are there complexities to do with tectonic shifts?

    Comment by Luke — 14 Jul 2007 @ 4:47 PM

  157. Yes, Luke, you’ll find those with Google Scholar. Some sites have gone back and forth as possible evidence one way or another, for example islands were found to have uplifted or sunk over the same period of time sea level changed, I recall. It’s been discussed here, search box may be helpful too.

    Comment by Hank Roberts — 14 Jul 2007 @ 5:38 PM

  158. We also had this piece that according to another blog contained this:

    During the last interglacial period (130-116 thousand years ago), the climate was 5 Ã�°C warmer than it is today, says Eske Willerslev, director of the centre for ancient genetics at the University of Copenhagen in Denmark. “Sea levels were 5-6 metres higher, and most scientific models have assumed that the melting of the southern Greenland ice cap was responsible. But our data suggest that this was not the case.”

    That comment could easily be interpreted as suggesting that most models have assumed Southern Greenland alone was responsible for that sea level rise. Is that the case, or Willerslev being excessively loose with the language?

    Comment by Alex J — 14 Jul 2007 @ 8:13 PM

  159. Re #158: Alex J — Excessively loose, IMHO.

    Comment by David B. Benson — 14 Jul 2007 @ 8:22 PM

  160. Re 155: Agreed. And even if that was the case, we could start by taking high fructose corn syrup out of bread, fruit juice and innumerable other foods where they have no reason to be. Those HFCSs are suspected to play a significant role in children obesity and other health problems. Having a better use for them might save us a tobacco-like fight…

    Comment by Philippe Chantreau — 15 Jul 2007 @ 7:36 PM

  161. Hi, everyone! First of all, this is my first post. I am pretty certain that this is the wrong place for this. Although I searched the RC site I could find no mention of ‘Climate change and trace gases’ HANSEN et al. 2007. http://pubs.giss.nasa.gov/docs/2007/2007_Hansen_etal_2.pdf
    I was looking for this and wondered if there was an idiot’s guide, or at least some kind of critique to help me better understand it?

    Comment by TotallyScrewed — 16 Jul 2007 @ 7:59 AM

  162. Climate change and trace gases
    BY James Hansen, Makiko Sato, Pushker Kharecha, Gary Russell, David W. Lea, AND Mark Siddall
    Phil. Trans. R. Soc. A (2007) 365, 1925â??1954
    http://pubs.giss.nasa.gov/docs/2007/2007_Hansen_etal_2.pdf

    Equation 2.1 on page 1928 reads:

    Fe=1.15[Fa({{CO}_{2}})+1.4Fa({CH}_{4})]

    … but it should be:

    Fe=1.15[Fa({{CO}_{2}})+1.4Fa({CH}_{4})+1.15Fa({N}_{2}O)]

    Comment by Timothy Chase — 16 Jul 2007 @ 10:24 AM

  163. Well, we know that rising sea levels are not due to Antarctic Ice melting or sea ice melting:

    Wingham, et al, Mass balance of the Antarctic ice sheet has found:

    We find that data from climate model reanalyses are not able to characterise the contemporary snowfall fluctuation with useful accuracy and our best estimate of the overall mass trend – growth of 27±29Gtyr^-1 – is based on an assessment of the expected snowfall variability. Mass gains from accumulating snow, particularly on the Antarctic Peninsula and within East Antarctica, exceed the ice dynamic mass loss from West Antarctica. The result exacerbates the difficulty of explaining twentieth century sea-level rise.

    The study went on to add that Antarctic ice build up was actually lowering the sea level by .18 mm per year.

    That brings up the accuracy of the measured sea level. Per Cazenave et al, 2003 the satellite measurement is only within 2-3 cm. To make the readings more accurate they then:

    The tide gauge calibration time series (Figure 6) is used to diagnose problems in the altimeter instrument, the orbits, the measurement corrections, and, ultimately, the final Geophysical Data Records (GDRs). Numerous improvements to the GDRs have been developed in this way and used to produce improved measurements (corrections to the official Geophysical Data Records (GDRs)), which are then recalibrated using the tide gauges.

    How ever using tide gages has problems as can be seen in
    Interannual sea level change at global and regional scales using Jason-1 altimetry http://sealevel.jpl.nasa.gov/science/invest-cazenave.html

    tide gauges have two drawbacks:
    1. their geographical distribution provides very poor sampling of the ocean basins, especially when studying the climatic signal over the past century, and
    2. they measure sea level relative to the land, hence recording vertical crustal motions that may be of the same order of magnitude as the sea level variation. High-precision satellite altimetry, in particular the TOPEX/POSEIDON mission, has demonstrated its capability to monitor sea level variations with great accuracy, high spatio-temporal resolution, global coverage of the oceans, and absolute sea level measurements in a terrestrial reference frame tied to the Earth’s center of mass [see Fu and Cazenave, 2001, for a review]. Analyses of TOPEX/POSEIDON altimetry data indicate that, in terms of global mean, sea level has risen by about two millimetres per year since early 1993 [e.g., Nerem and Mitchum, 2001a, b; Cabanes et al., 2001; see also figure 1].

    Another part of the sea level is the normal oscillation in both the Pacific and Atlantic.

    A significant fraction of this change has also been shown to arise from changes in the Southern Ocean [Cabanes et al., 2001a]. The observations also show a 15-mm rise and fall of mean sea level that accompanied the 1997-1998 El Nino-Southern Oscillation (ENSO) event [Nerem et al., 1999; White et al., 2001].

    So does anyone know where there is a break down of how much the sea level is dropping by melting sea ice, how much it is rising due to Greenland icecap melting, now, how much is due to the various oscillations, PDO or ADO?

    Comment by Vernon — 16 Jul 2007 @ 11:40 AM

  164. PS my post 162

    My mistake.

    Looking at the text more closely, 0.15 in the 1.15 on the outside is supposed to take care of the nitrous oxide. A little odd, though, since nitrous oxide can vary independently of carbon dioxide and methane.

    What is going on there?

    Response: You are confusing two things here. The first is the relative efficacy of the CH4 forcing to the CO2 forcing. Hansen in 2005 showed that for the same radiative forcing, CH4 has ~40% more impact on temperature than CO2 (this is on top of the differences on a per molecule basis). Hence the 1.4 factor. The second issue is that the data for N2O just aren’t as complete as for CH4 and CO2, but a rough calculation of the effect over glacial/interglacial cycles is that N2O adds about 15% to the total forcing. Hence the 1.15 multiplying the CO2+CH4. That’s not ideal since you lose the independent nature of the nitrogen ycle, but is probably the best one can do for the moment. – gavin]

    Comment by Timothy Chase — 16 Jul 2007 @ 11:44 AM

  165. Vernon

    Your link to the Wingham paper appears to be dead.

    Wingham, D.J., Shepherd, A., Muir, A. and Marshall, G.J. 2006.
    “Mass balance of the Antarctic ice sheet. Philosophical Transactions
    of the Royal Society A, 364: 1627-1635.

    New link here:

    http://bowfell.geol.ucl.ac.uk/~lidunka/EPSS-papers/djw3.pdf

    Comment by Hugh — 16 Jul 2007 @ 12:44 PM

  166. Vernon, asking again, what sources are you relying on for the earlier statements you made?

    On the altimetry data, I’d ask the icecap experts if there’s any contradiction in all these reports — seems to me it’s not inconsistent to have observations including
    — more meltwater flowing out at the edges (mass balance studies)
    — more ice varying in surface elevation as water flows under it (the lakes and rivers under the icecap are being found more often and observed)
    — more liquid water and voids under the ice, and more fast-moving water under the ice (look for ‘drumlin’ in Antarctic reports)
    — the top of the ice rising as snow accumulates (the Wingham paper)

    Snow’s light and fluffy for a few years. The ice melting at the bottom is as dense as it gets. I recall ‘icequakes’ occur in Antarctica too.

    Comment by Hank Roberts — 16 Jul 2007 @ 1:16 PM

  167. Re: Comment by Vernon 16 Jul 2007 11:40 am

    Thanks for the reference. I note that Wingham arrives at a value of 27+/-29 Gt/yr from data covering 72% of the icesheet for the period 1992-2003.

    This result is to be contrasted with the GRACE results indicating loss for the West Antarctic ice sheet of 148 +/- km^3/yr and the East Antarctic Ice sheet of 0+/-56 km^3/yr for the period 2002-2006. (Velicogna and Wahr, Science 2006). This is disquieting, for it seems that Antarctica has begun melting quickly in the last 5 years.

    Comment by sidd — 16 Jul 2007 @ 1:52 PM

  168. Re 163 Vernon:
    Seems that you are overlooking good old thermal expansion, which I’ve seen up to half of current rise attributed to.

    Comment by Jim Eager — 16 Jul 2007 @ 2:04 PM

  169. Re: Comment by Hank Roberts 16 Jul 2007 1:16 pm
    “Snow’s light and fluffy for a few years. The ice melting at the bottom is as dense as it gets.”

    The values used in the Wingham reference are 0.35g/cc for snow and 0.917g/cc for old ice

    Re: Comment by sidd � 16 Jul 2007 @ 1:52 pm

    I did not include the uncertainty in the WAIS mass loss estimate. Velicogna and Wahr estimate 148+/-21 km^3/yr for WAIS mass loss rate.

    Comment by sidd — 16 Jul 2007 @ 2:56 PM

  170. RE: 168 Jim, you melt ice on this scale and you get very cold water which takes less volume than the ice did. This would also tend to cool the water as the sea ice melts.

    I ask these things because I have not seen a satellite based study that shows melting in Antarctic and it seems to be the oscillations cause bigger short term sea level change than any thing else.

    So, I again ask, can anyone point me to a study that addresses all the relevant forcings: sea ice melting, occilations, Antarctice ice mass growth, and Greenland Ice mass melting? I would like one that identifies the contribution of each forcing so we can see what the actual trend is.

    Comment by Vernon — 16 Jul 2007 @ 3:17 PM

  171. Vernon, unless you have a subscription, or access to a library where you can read it, most of the current work is behind the subscription wall of _Science_ magazine. You can read the abstracts.

    You may find this one particularly helpful:
    http://www.sciencemag.org/cgi/content/abstract/sci;315/5818/1529

    Science 16 March 2007:
    Vol. 315. no. 5818, pp. 1529 – 1532
    DOI: 10.1126/science.1136776

    Recent Sea-Level Contributions of the Antarctic and Greenland Ice Sheets
    Andrew Shepherd1 and Duncan Wingham

    “… data show that Antarctica and Greenland are each losing mass overall. Our best estimate of their combined imbalance is about 125 gigatons per year of ice, enough to raise sea level by 0.35 millimeters per year. This is only a modest contribution to the present rate of sea-level rise of 3.0 millimeters per year. However, much of the loss from Antarctica and Greenland is the result of the flow of ice to the ocean from ice streams and glaciers, which has accelerated over the past decade. In both continents, there are suspected triggers for the accelerated ice dischargeâ��surface and ocean warming, respectivelyâ��and, over the course of the 21st century, these processes could rapidly counteract the snowfall gains predicted by present coupled climate models.”

    Below is a search for this year’s articles.

    http://scholar.google.com/scholar?hl=en&lr=&safe=off&scoring=r&q=melting+Antarctica&as_ylo=2007&btnG=Search

    Comment by Hank Roberts — 16 Jul 2007 @ 5:17 PM

  172. Is there any systematic monitoring / reporting of the ocean floor methane venting being detected by shipping? Apparently hazard alarms are being tripped – eg see http://archives.zinester.com/13183/118372.html Is increased methane venting from the ocean floor to be expected?

    QUOTE: According to U.S. maritime industry sources, tanker captains are reporting an increase in onboard alarms from hazard sensors designed to detect hydrocarbon gas leaks and, specifically, methane leaks. However, the leaks are not emanating from cargo holds or pump rooms but from continental shelves venting increasing amounts of trapped methane into the atmosphere. With rising ocean temperatures, methane is increasingly escaping from deep ocean floors. Methane is also 21 more times capable of trapping heat in the atmosphere than carbon dioxide.

    In fact, one of the major sources for increased methane venting is the Hudson Submarine Canyon, which extends 400 miles into the Atlantic from the New York-New Jersey harbor. Another location experiencing increased venting is the Santa Barbara Channel on the California coast. END-QUOTE

    Comment by Luke — 16 Jul 2007 @ 5:42 PM

  173. Re 162 & 164

    Last fall, I seem to remember some anomalously high atmospheric methane measurements at sea level, near leads in the ice over the Sea of Leptev. Now that the ice has melted, has anyone determined the cause of the high readings?

    If it was hydrate decomposition (resulting in the water turnover that caused last springâ��s early melting of the sea ice) then some of this discussion may be – moot.

    If those high atmospheric methane readings were not a result of methane hydrate decomposition, has anyone measured how close various hydrate deposits around the world are to conditions that would trigger their decomposition?

    Comment by Aaron Lewis — 16 Jul 2007 @ 5:43 PM

  174. > Maritime …. methane
    The Wayne Madsden link has two followups on his site, but all three articles are behind a pay-to-view wall. I didn’t find any other sources for the info, just that same quote repeated several places (including an armageddon site and a ‘Planet X’ site, so one has to wonder ….)

    I’d think the climatologists might want to inquire of any of the reputable marine gas sensor companies
    (Google Ad Server’s good for something at last!).
    One is: http://www.martek-marine.com

    If they’re doing business, they’re keeping track of false positive alarms on their equipment and thinking about how to adjust if the environmental background of the gas at sea level in harbors actually is changing. The’d have to know the baseline amount.

    Could be it’s just a rumor. Anyone paid the fee to read the original items?

    Comment by Hank Roberts — 16 Jul 2007 @ 6:27 PM

  175. Methane Seeps

    Luke (#172) wrote:

    In fact, one of the major sources for increased methane venting is the Hudson Submarine Canyon, which extends 400 miles into the Atlantic from the New York-New Jersey harbor. Another location experiencing increased venting is the Santa Barbara Channel on the California coast.

    There is a methane seep in the Hudson Submarine Canyon, but you have to go back to 2001 to find any mention of it in credible sources. Everything recent, as far as I can see, has been in blogs and certain radio talkshows.

    Comment by Timothy Chase — 16 Jul 2007 @ 6:58 PM

  176. RE: 170 Vernon: “Jim, you melt ice on this scale and you get very cold water which takes less volume than the ice did. This would also tend to cool the water as the sea ice melts.”

    Yes, but that is a regional change. What I meant was thermal expansion of the *entire* ocean as global temperature rises.

    Comment by Jim Eager — 16 Jul 2007 @ 8:33 PM

  177. I cannot find a study that is not talking about Antarctic sea ice when making claims that the Antarctic is melting. Since we know that sea ice melting does not raise sea levels and based on what we are seeing in the Arctic, may actually lower sea levels, can any one point at a study that actually checks the Antarctic ice cap as Wingham et al did?

    It seems very disingenuous to imply that sea ice melting is causing sea levels to rise.

    [Response: Sea ice melting does cause sea level to rise (only a little though because of the difference in salt content - melted sea ice is fresh water, but displaces salt water which takes up less volume). But Antarctic sea ice is pretty stable for the moment. - gavin]

    Comment by Vernon — 17 Jul 2007 @ 7:19 AM

  178. Vernon

    The Shepherd and Wingham paper that Hank points you to in #171 appears to present a step in the right direction:

    However, much of the loss from Antarctica and Greenland is the result of the flow of ice to the ocean from ice streams and glaciers, which has accelerated over the past decade.

    Nothing about sea ice there.

    Comment by Hugh — 17 Jul 2007 @ 9:53 AM

  179. Yep. Vernon, as I’ve asked repeatedly, _where_ are you getting your information? Wingham’s two papers for example — you got part of one (snowfall in Antarctica) but missed his review of the overall issue. That suggests you’re looking at a secondary source, instead of doing your own research. Seriously, tell us _how_ you’re finding “nothing” and we can help you look better.

    This is _really_helpful:
    How To Ask Questions The Smart Way
    Guide to teach how to ask technical questions in a way more likely to get a satisfactory answer.
    http://www.catb.org/~esr/faqs/smart-questions.html

    Comment by Hank Roberts — 17 Jul 2007 @ 10:12 AM

  180. RE 178: Wingham has the continental ice sheets growing not melting which even with the increased ice flows, he found:

    This range equates to a sea level contribution of K0 -.3�+C0.1 mm yrK1 and so Antarctica has provided, at most, a negligible component of observed sea-level rise.

    So while the Antarctic is currently lowering the sea level, Arctic sea ice melting is doing nothing to the sea level (even counting Gavin’s slight gain due to salinity, it would be pretty close to 0 long term). That only leaves Greenland and the Oscillations, and I have not seen any studies that actually show what the sea level impact is of Oscillations other than the Cazenave et al, 2003.

    The most recent determinations are 1.76 ± 0.55 mm/yr [Douglas, 2001] and 1.84 ± 0.35 mm/yr after correcting for postglacial rebound [Peltier, 2001]. Church et al. [2001] adopt as a best estimate a value of 1.5 ± 0.5 mm/yr and note that the sum of climate-related components is low (0.7 mm/yr) compared to observations. In effect, the observed value is more than twice as large as the revised estimate of the total climate contributions, although there is complete overlap between their respective uncertainties. It thus appears that either the climate-related processes causing sea level rise have been underestimated or the rate of sea level rise observed with tide gauges is in error. Munk [2002] refers to this as ��The Enigma.��

    Which I take to mean that the satellite data indicates a steady trend of just under 2 mm per year where as the tide gages give just under 4 mm per year. There appears to be the assumption that if the satellite data does not support the tide gages, then the satellite data is biased and is being corrected as I addressed in #163.

    So Hugh, what was that question again?

    Comment by Vernon — 17 Jul 2007 @ 10:27 AM

  181. Re 180 Vernon: “That only leaves Greenland and the Oscillations”

    Which means you are still ignoring thermal expansion as SST rises.

    Comment by Jim Eager — 17 Jul 2007 @ 11:59 AM

  182. RE 181: I believe that none of the studies have identified how much thermal expansion there is since the oscillation can cause up to 15mm rise or drop in one year. That is why I am asking if anyone can reference a study that actually addresses all the elements of sea level change.

    From what I have read, the tide gages indicate x amount of sea level rise, but the satellites data does not so it is corrected for this bias with the trend from the tide gages… does this sound familiar?

    There are studies that actually looked that the increase in ice mass in Antarctica that show there is actually a negative impact on sea level rise. There studies that show that the Arctic sea level has been dropping.

    This means that I have not seen a study that actually addresses thermal expansion in light of the other aspects. On, and per the proxy evidence the SST has been dropping for quite a while.

    [Response: Try Ishii et al (poster wcrp.ipsl.jussieu.fr/Workshops/SeaLevel/Posters/3_3_Ishii.pdf ) - long term trends of steric sea level rise are positive. Why do you think that SST proxies show cooling? Try looking at the coral data... - gavin]

    Comment by Vernon — 17 Jul 2007 @ 12:29 PM

  183. Vernon, is either of these websites the source you are trusting for what you believe is science information? Or are you writing there?

    I searched for your belief above and found it on these two pages (and nowhere else). They’re not science sites.

    World Climate Report » Sea Level Rise? – Not From Antarctic Melting
    “Antarctica has provided, at most, a negligible component of observed sea-level rise. …”
    worldclimatereport.com/index.php/2006/12/05/sea-level-rise-not-from-antarctic-melting/

    Signs of the Times Forum / Fire and Ice: The Day After Tomorrow
    “Antarctica has provided, at most, a negligible component of observed sea-level rise …”
    signs-of-the-times.org/signs/forum/viewtopic.php?id=4764

    Comment by Hank Roberts — 17 Jul 2007 @ 12:43 PM

  184. No Hank, through iteration Vernon has come up with something which I am finding very interesting.

    That quote:

    Even allowing a +/- 30 Gt yr fluctuation in unsurveyed areas, they provide a range of 35 +/- 115 Gt yr. This range equates to a sea level contribution of -0.3 +/- 0.1 mm yr and so Antarctica has provided, at most, a negligible component of observed sea-level rise.”

    Is peer-reviewed it’s in the conclusion of the Wingham cite above and here:

    http://bowfell.geol.ucl.ac.uk/~lidunka/EPSS-papers/djw3.pdf

    Vernon, thanks…this is making for really interesting reading.

    Comment by Hugh — 17 Jul 2007 @ 1:10 PM

  185. Hugh, did you read all the way to the Conclusions section of the Wingham cite from 2006? Vernon didn’t give you that.

    They wrote:

    “What is clear, from the data, is that fluctuations in some coastal regions reflect long-term losses of ice mass, whereas fluctuations elsewhere appear to be short-term changes in snowfall. While the latter are bound to fluctuate about the long-term MAR, the former are not, and so the contribution of retreating glaciers will govern the twenty-first century mass balance of the Antarctic ice sheet.”

    Look at the picture in that article. See where there’s loss versus gain?

    And, Hugh, read at least the abstract linked in 171.
    Here, for your convenience:
    http://www.sciencemag.org/cgi/content/abstract/sci;315/5818/1529

    “”… data show that Antarctica and Greenland are each losing mass overall…. However, much of the loss from Antarctica and Greenland is the result of the flow of ice to the ocean from ice streams and glaciers, which has accelerated over the past decade…. over the course of the 21st century, these processes could rapidly counteract the snowfall gains predicted by present coupled climate models.”

    Anything not clear about that?
    Coauthor is the same Dr. Wingham; conclusion is the same as above!

    Science 16 March 2007: Vol. 315. no. 5818, pp. 1529 – 1532
    DOI: 10.1126/science.1136776

    Recent Sea-Level Contributions of the Antarctic and Greenland Ice Sheets
    — Andrew Shepherd and Duncan Wingham

    Don’t trust summaries from World Climate Report (Greening Earth Society/Western Fuels Association/Pat Michaels) — that’s a PR site run by and for the coal lobby.

    Vernon, the Arctic sea level change story is probably coming to you third hand from this news report of one study. At least read the BBC story:
    http://news.bbc.co.uk/2/hi/science/nature/5076322.stm

    You should also look that up in Google Scholar by author name for more.

    Comment by Hank Roberts — 17 Jul 2007 @ 1:50 PM

  186. Thank you Hank, however, what’s going to be the dominant forcing on sea level rise in the 21st century is not what Vernon is asking.

    From my reading of his question he is asking for a summary of contemporary effects which explains the current discrepancy between the estimated rise and the satellite data i.e. the difference between ~2mm/yr and ~4mm/yr (or am I off base here?).

    It seems like a reasonable question considering the fact that this discrepancy has been termed (in 2002) an “enigma”

    http://www.pnas.org/cgi/content/abstract/99/10/6550?ijkey=c398bfa468f139feef6884b2a78ea2fdf31f38e7&keytype2=tf_ipsecsha

    That I have found that the question Vernon asked has led me to undertake some ‘really interesting reading’ and has guided me toward actually reading other resources such as this:

    http://www.ingentaconnect.com/content/klu/10236/2006/00000056/F0020005/00000046?crawler=true

    and this:

    http://www.journals.royalsoc.ac.uk/content/786m1766t6337892/

    and chapter 5.5 of this:

    http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Pub_Ch05.pdf

    …should not be taken as an indication that from here on in I intend to formulate my opinions by reading Pat Michaels, thank you.

    [edited]

    Best Wishes

    Comment by Hugh — 17 Jul 2007 @ 3:30 PM

  187. Good. You’re looking at the same issue Rahmstorff and others have been talking about.

    Vernon wrote above: “Antarctic ice build up was actually lowering the sea level” — but that’s not what the paper said. Sea level isn’t getting lower. As long predicted, there’s more snow in central Antarctica, and if not for that the rate of sea level rise would be slightly greater. It’s already rising faster than anyone expected.

    The “Arctic ocean” studies — two, both using satellites in the absence of any tide gauge data — have huge central blank spots around the North Pole. Something’s up, but they can’t tell what is happening.

    I just worry when people come along and seem to think that sea level is actually falling from misreading the papers.

    Clicking the “citation” button leads to more info, as always.
    Science 4 May 2007:
    Vol. 316. no. 5825, p. 709
    DOI: 10.1126/science.1136843

    Recent Climate Observations Compared to Projections
    Stefan Rahmstorf,1 Anny Cazenave,2 John A. Church,3 James E. Hansen,4 Ralph F. Keeling,5 David E. Parker,6 Richard C. J. Somerville5

    ” … The data available for the period since 1990 raise concerns that the climate system, in particular sea level, may be responding more quickly to climate change than our current generation of models indicates.”

    Which brings us back to Greenland, where we have icequakes, outflows from glaciers, and surface melting all increasing.

    Comment by Hank Roberts — 17 Jul 2007 @ 7:11 PM

  188. Thanks, Gavin, for the sea level change poster pointer (#183) — that _is_ good. Reposting, making it clickable: http://wcrp.ipsl.jussieu.fr/Workshops/SeaLevel/Posters/3_3_Ishii.pdf

    Comment by Hank Roberts — 17 Jul 2007 @ 8:33 PM

  189. RE: 187 Hank, read the study which I did quote correctly and it does say that the ice build up in the Antarctic is actually lowering the sea level. Not that the sea level is going down but that the Antarctic is not the source of the sea level rising.

    Comment by Vernon — 18 Jul 2007 @ 3:13 AM

  190. Re #187/8: Hank, there’s been some questioning of sea level trends over at RP Sr.’s in the last few days, so perhaps that’s it.

    There’s also this paper, which appears to be contemporaneous with the poster in #188, plus here’s yet another related poster. I haven’t looked at them carefully to see how they relate. Given the timing, I assume Rahmstorf et al must have taken all of them into account.

    Comment by Steve Bloom — 18 Jul 2007 @ 5:26 AM

  191. Hank, you complain when I don’t list my sources and then when I do, you attribute what I say to something other than the source I reference.

    I never said that sea levels were dropping anywhere but the Arctic, which if you will look at the relevant studies done using satellite based sea level measurement, you will find that the sea level is falling in the Arctic.

    Now I said that the net contribution to sea level rise based on the fore mentioned studies by the Antarctic is negative. That means that if there is no other factors and only the Antarctic, then yes, sea levels would be dropping, but it is not and sea levels are not, and that is not what I said.

    Hugh got it right when he said:

    From my reading of his question he is asking for a summary of contemporary effects which explains the current discrepancy between the estimated rise and the satellite data i.e. the difference between ~2mm/yr and ~4mm/yr (or am I off base here?).

    So, have you found any studies that explain why the ~2mm/yr trend measured by satellites does not match the tide gage measurements. Also, since tide gage measurements are not done world wide but are actually very limited in scope, why they would be used to impose a trend on the satellite measurements?

    Comment by Vernon — 18 Jul 2007 @ 5:33 AM

  192. In light of the discussion about sea levels i’ve recently come across a couple of mentions re Dr Nils Axel Morner from Sweden. He apparently withdrew from IPCC – here’s a taster of what he claims “paleogeophysicist Nils-Axel Mörner, whoâ??s been studying and writing about sea levels for four decades, the scientists working for the IPCC have falsified data and destroyed evidence to incorrectly prove their point”.

    Now I see on google that the usual suspects have embraced him incl larouche & extreme sceptic UK columnist Melanie Philips but that doesn’t necessarily mean he is wrong, though seems very trenchent critisim.

    Not being in a position to really appraise his scientific work etc I was hoping someone here would be able to give a more independent critical assessment of both his claim re sea levels not rising and his outburst re IPCC. Sorry not to provide a cite to any published paper, it was more the general tenet of his argument i was interested in seeing evaluated.

    thanks

    Comment by kevin rutherford — 18 Jul 2007 @ 6:50 AM

  193. re: 191. There are several comments re: Morner’s “work” in the responses to comment #1 at http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument-part-ii/index.php?p=97#comment-724

    Comment by Dan — 18 Jul 2007 @ 9:16 AM

  194. http://www.realclimate.org/index.php?p=314 Sea level in the Arctic

    Comment by Hank Roberts — 18 Jul 2007 @ 9:56 AM

  195. Vernon, I continue to ask you for your sources because you’re saying things without sources.
    If you’ll say what you’re quoting, that’ll help — full cites so people can read the context.
    When you just assert things, you seem to be manufacturing a controversy where none exists.
    Undertainty isn’t unusual in science; there’s no ultimate proof, there are observations to make sense of.

    The variation in the data from tide and satellites isn’t a contradiction or a problem or a weakness — you’re describing how science is put together, from various tools and sources.

    Read here: http://www.realclimate.org/index.php/archives/2007/03/the-ipcc-sea-level-numbers/#more-427
    Look at this: http://www.realclimate.org/images/sealevel_2.jpg
    That chart cites its source: http://www.agu.org/pubs/crossref/2004…/2003RG000139.shtml

    (This is why it’s good to cite sources, so people can look them up. Please do this.)

    There’s one very important word in this abstract: “geocentric” — that probably explains your question.

    “… the geocentric rate of global mean sea level rise over the last decade (1993-2003) is now known to be very accurate, +2.8 ± 0.4 mm/yr, as determined from TOPEX/Poseidon and Jason altimeter measurements, 3.1 mm/yr if the effects of postglacial rebound are removed. This rate is significantly larger than the historical rate of sea level change measured by tide gauges during the past decades (in the range of 1-2 mm/yr)…. questions about whether the rate of 20th century sea level rise, based on poorly distributed historical tide gauges, is really representative of the true global mean. Such a possibility has been the object of an active debate, and the discussion is far from being closed.”

    Science — it just works.

    Comment by Hank Roberts — 18 Jul 2007 @ 10:53 AM

  196. Re #191: [I never said that sea levels were dropping anywhere but the Arctic...]

    Am I missing something here? How can sea levels change in the Arctic, but not elsewhere? Water flows, so I’d think any local change – say a big chunk of Greenland ice falling into the sea – would be felt worldwide within a few days at most.

    Of course you do have a lot of circumpolar land rising due to post-glacial rebound. The denialist camp could try to spin that as a dropping sea level to the general public, but surely you wouldn’t try that here :-)

    Comment by James — 18 Jul 2007 @ 12:51 PM

  197. James, it’s a basin surrounded by land with small connections at sea level, rivers contributing to it, ice, wind patterns and much else, and poorly instrumented. The satellites don’t go exactly over the pole so there’s a big blank area still in the satellite studies. This is all quite new work being figured out. A little searching:

    Observations of Polar Ice With Spaceborne Altimeters: Recent …
    Arctic sea level change from satellite altimetry. * Scharroo, R
    http://www.agu.org/meetings/sm06/sm06-sessions/sm06_G21A.html

    Sea level variability in the Arctic Ocean from AOMIP models
    by Scharroo et al. [2006] based on satellite observations over the entire Arctic Ocean. The sea level time series obtained from this study …
    http://efdl.cims.nyu.edu/project_aomip/publications/jgr_2006/proshutinsky_sealevel.pdf

    Recent Decrease of Sea Level Pressure in the Central Arctic
    JE Walsh, WL Chapman, TL Shy – Journal of Climate – ams.allenpress.com
    … Satellite passive microwave data and/or under ice draft …
    The Northern Hemisphere sea level pressure data …
    http://ams.allenpress.com/amsonline/?request=get-abstract&doi=10.1175%2F1520-0442(1996)009%3C0480:RDOSLP%3E2.0.CO%3B2

    ‘Sea level in the Arctic is falling’
    Answer: Yes, a new study using Europe’s Space Agency’s ERS-2 satellite has determined that over the last 10 years, sea level in the Arctic Ocean has been … http://gristmill.grist.org/story/2006/11/9/162012/366

    Comment by Hank Roberts — 18 Jul 2007 @ 1:13 PM

  198. RE: 196 I think that if you go and read the studies based on satellite measurements, the sea levels the rate of sea levels rising or fall varies from sea to sea. Please do not take my word for it… google it for your self.

    Comment by Vernon — 18 Jul 2007 @ 2:16 PM

  199. This may help for the past century’s info.
    This does _not_ talk about satellite work (see the above for that).

    http://www.journals.royalsoc.ac.uk/content/f6v6775433542251/

    On the rate and causes of twentieth century sea-level rise
    Issue Volume 364, Number 1841 / April 15, 2006
    Pages 805-820
    DOI 10.1098/rsta.2006.1738
    Laury Miller 1, Bruce C. Douglas 2

    1 NESDIS, NOAA Laboratory for Satellite Altimetry Silver Spring, MD 20910-3282, USA
    2 Florida International University Laboratory for Coastal Research Miami, FL 33199, USA

    ——Abstract——-

    Both the rate and causes of twentieth century global sea-level rise (GSLR) have been controversial. Estimates from tide-gauges range from less than one, to more than two millimetre/yr^-1. In contrast, values based on the processes mostly responsible for GSLR – mass increase (from mountain glaciers and the great high latitude ice masses) and volume increase (expansion due to ocean warming) – fall below this range.

    Either the gauge estimates are too high, or one (or both) of the component estimates is too low.

    Gauge estimates of GSLR have been in dispute for several decades because of vertical land movements, especially due to glacial isostatic adjustment (GIA). More recently, the possibility has been raised that coastal tide-gauges measure exaggerated rates of sea-level rise because of localized ocean warming.

    Presented here are two approaches to a resolution of these problems.

    The first is morphological, based on the limiting values of observed trends of twentieth century relative sea-level rise as a function of distance from the centres of the ice loads at last glacial maximum. This observational approach, which does not depend on a geophysical model of GIA, supports values of GSLR near 2mmyr^-1.

    The second approach involves an analysis of long records of tide-gauge and hydrographic (in situ temperature and salinity) observations in the Pacific and Atlantic Oceans. It was found that sea-level trends from tide-gauges, which reflect both mass and volume change, are 2-3 times higher than rates based on hydrographic data which reveal only volume change.

    These results support those studies that put the twentieth century rate near 2mm/yr^-1, thereby indicating that mass increase plays a much larger role than ocean warming in twentieth century GSLR.

    —– END ABSTRACT — [paragraph breaks added for readability -hr]

    Many of the references to the above page are also clickable links.
    Now — Greenland thread? The above covers the past century. What’s happening now that will affect this century?

    Comment by Hank Roberts — 18 Jul 2007 @ 3:10 PM

  200. Vernon, you wrote:
    “go and read the studies…. google it for your self.”

    You keep coming back to the assertion that sea levels in different places must be going up and down.

    It’s a bogus argument being made to claim that the big ice masses like Greenland can’t be melting. You can find _that_ plenty of places on the Internet. Not science. Check the sources.

    This speaks directly to that claim:

    http://www.grdl.noaa.gov/SAT/pubs/papers/2004nature.pdf

    “Concerning the causes of sea level rise, our results provide clear
    evidence that changes in ocean volume due to temperature and
    salinity account for only a fraction of sea level change, and that mass
    change plays a dominant role in twentieth-century GSLR. This
    aspect of our results is consistent with the results of Antonov et al.7,
    who show that the global oceans freshened during the latter half of
    the twentieth century by an amount equivalent to 1.4mm/yr21 of
    fresh water, but goes further by indicating that the source must be
    continental. The only alternative to this interpretation is that what
    we identify as mass change is actually a mass redistribution within
    the global ocean rather than a mass increase due to the addition of
    fresh water. However, for this to be true, large areas of the global
    ocean would have to have falling sea levels for the entire twentieth
    century. Observations from the global tide gauge network, consisting
    mostly of gauge sites located along themargins of the ocean basins, do
    not support this viewpoint. Whether the mid-oceans are currently
    undergoing such changes can only be determined from long-term, high-
    precision satellite altimeter missions, such as the TOPEX/ Poseidon
    and Jason missions, which are at present under way.”

    Just sending people to Google means they find everything, some of it nonsense.

    Who do you consider reliable as the source for what you believe?

    Comment by Hank Roberts — 18 Jul 2007 @ 5:40 PM

  201. Great site. Most interesting. I have a number of questions, though, that I haven’t yet found a decent answer to. As a scientist who deals with the output of biological systems I’m very much aware that data quality is absolutely critical if you are to generate good models especially in multifactorial systems. Therefore the use of ice cores as a reference database has always made me a little nervous. Part of that may or course be my own ignorance. So, perhaps you could answer a few questions. Firstly, whilst diffusion rates of gases in solids are pretty slow they are not insignificant especially when judged over large timescales. These ice cores are not single crystal lattices so I’d expect gas diffusion to be nightmare as there are so many propogation paths within various crystals and their boundaries. Given that there are also pressure changes over the length of ice cores, do you have to correct for both compression changes once the core is removed and also changing gas diffusion properties that you see at pressure? Have any of these effects been seen or measured? There are a number of other factors which I might raise but I’m curious to know if the gas diffusion effect has been observed at all. Thanks in advance. Keep up the good work, difficult as it may be.

    Comment by Keith — 19 Jul 2007 @ 11:05 AM

  202. Hank [edited] putting words into my mouth that I did not say. What I pointed out is that the sea level in the arctic is falling, which is even addressed on this site, so yes it is happening.

    The change in sea level is not homogeneous, but rather the mean of the global sea level change. There are many papers on this but Jevrejeva, et al (2005) says:

    The major contributions to the global sea level rise during 1920�1940 are from the northwestern Atlantic (4.2 ± 1.0 mm/yr), Indian (3.5 ± 1.0 mm/yr), and Mediterranean (3.1 ± 1.0 mm/yr) regions.

    I could have used others but the generally present graphics and this was easier to point to. [edited] What I asked was since the tide gage and satellites give different answers, and it appears that the rate of change from the satellites is fairly static, then why did the rate of change from the tide gages get appended to the satellite data to correct it.

    I also pointed out other peer reviewed papers that show that tide gages are not a good way to measure sea level change.

    What I believe is that no one has answered my question [edited]

    As for your quote, I could be wrong but I would think that melting sea ice from both the Arctic and the Antarctic could account for a significant amount of fresh water being added. But that would raise sea levels, however, the Arctic sea level is dropping.

    Comment by Vernon — 19 Jul 2007 @ 11:42 AM

  203. These may help, though this isn’t specific to the topic here about Greenland ice cores.
    This is an early doc but will lead you to more recent work, see ‘relaxation’ and ‘crystal structure’ in the text: http://www.gisp2.sr.unh.edu/PERSONALHTML/ajgow.html

    More generally, you’ll find discussion like this:
    http://www.google.com/search?hl=en&safe=off&q=diffusion+ice+core+rate+layer+%2Brealclimate+precision&btnG=Search

    Likely you’ve seen the biological papers, such as this one, talking about correlating pollen with ice layers:
    http://intl-ppg.sagepub.com/cgi/content/abstract/27/4/548

    Comment by Hank Roberts — 19 Jul 2007 @ 12:00 PM

  204. Re #197: [(The Arctic ocean is) a basin surrounded by land with small connections at sea level, rivers contributing to it, ice, wind patterns and much else, and poorly instrumented.]

    Small connections? IIRC the Bering Strait is about 50 miles wide, the Baffin Strait several hundred. Then there’s the gap between Greenland & Europe, with only Iceland in it.

    I just don’t see how, absent significant changes in wind patterns or currents, you could get different sea levels in different places.

    Comment by James — 19 Jul 2007 @ 12:15 PM

  205. How much have you read, James?

    Do you know how deep the ocean is on either side of those connections, and how deep the basins are on either side? If not some of these may help:
    http://www.google.com/search?hl=en&safe=off&q=%2B%22Arctic+Ocean%22+%2Bsill+%2Bdepth+%2Bwind+-%22South+Pacific%22+-%22Black+Sea%22&btnG=Search

    You write “absent significant changes in wind patterns or currents” you can’t understand how sea level there could change. Why are you ruling out known causes? These are known, among other factors.

    What’s left, if you rule out the factors already known? Is there another explanation?

    Comment by Hank Roberts — 19 Jul 2007 @ 1:22 PM

  206. Auoting from the story I linked earlier:

    “This is something like decadal variability. Sea level goes up and down, up and down – but in general, it rises,” the principal investigator from project explained.

    “In order to make any conclusions it’s necessary to have long-term time series. We need much more data, and that’s why we will have this International Polar Year. When we combine satellites, submarines, drifting buoys, and tide gauges to get more dense data, we will be able to answer these questions.”
    http://news.bbc.co.uk/2/hi/science/nature/5076322.stm

    http://www.whoi.edu/science/PO/arcticsealevel/index.html

    If you read nothing else, read the conclusions:
    http://www.whoi.edu/science/PO/arcticsealevel/conclusions.html

    Everyone’s awaiting results from the current International Polar Year studies.

    Comment by Hank Roberts — 19 Jul 2007 @ 1:35 PM

  207. Vernon, you said what appears to you:

    “it appears that the rate of change from the satellites is fairly static”

    Then you asked:

    “… why did the rate of change from the tide gages get appended to the satellite data to correct it.”

    I don’t know. Who says it happened? Who says that’s why they did it? Give a source we can read with your statements, and we might be able to help you understand what you’re reading.

    Let’s try a picture. This _shows_ the satellite measurements (red) and the tide gauge measurements (black). Do you see a problem here? Does this help? Read the explanation too.

    http://www.globalwarmingart.com/wiki/Image:Recent_Sea_Level_Rise_png

    Comment by Hank Roberts — 19 Jul 2007 @ 2:15 PM

  208. Vernon, did you read the full paper you refer to?
    The bit you quoted is the bit that you’d find at CO2Science, if you found it there, but you should read the whole paper.

    In the full paper their next sentence is:

    “… Even smoothed by the 30 year SSA window, the trends from the different ocean regions show slightly dissimilar patterns and still demonstrate some cyclic variability. This cyclicity is associated with longer term oceanic variations, changes in thermal expansion and water mass adding to the ocean, which may provide non uniform regional sea level rise, and melting of continental ice leads to the significant geographic variations in the sea level change due to both gravitational and loading effects….”

    In their Abstract, they write:

    “We remove 2-30 year quasi-periodic oscillations and determine the nonlinear long-term trends for 12 large ocean regions. In contrast with linear trends, where the rate of mean sea level rise is constant, our results reveal the evolution of sea level rise during the 20 century and show that the highest regional rates of up to 3-5 mm/yr occurred between 1920-1950 (with some regional variations). Our global sea level trend estimate of 2.4 mm/yr for the period from 1993 to 2000 is comparable with the 2.6 mm/yr sea level rise calculated from TOPEX/Poseidon altimeter measurements….”

    No surprise there. The warming signal in the oceans isn’t new. The worry is how long it will go on and what Greenland’s melting, among other land sources, will add to it. For example:

    http://www.nersc.gov/news/annual_reports/annrep05/assets/img/research_news/01-heat_clip_image002.jpg
    “The half-degree temperature rise is similar to that observed during the second half of the 20th century, but the projected sea level rise is more than twice the 5-centimeter (2-inch) rise that occurred during that period. These numbers do not take into account fresh water from melting ice sheets and glaciers, which could at least double the sea level rise caused by thermal expansion alone…. 100 years after stabilization in the study, ocean waters continue to warm and expand, causing global sea level to rise unabated (Figure 1).”

    I’m done. Tired of asking for sources, and tired of finding them, for your questions for now. Good luck, keep reading, check your footnotes.

    Comment by Hank Roberts — 19 Jul 2007 @ 2:55 PM

  209. James (#204 wrote:

    Small connections? IIRC the Bering Strait is about 50 miles wide, the Baffin Strait several hundred. Then there’s the gap between Greenland & Europe, with only Iceland in it.

    Well, it isn’t just the width of the connections, but the depth. Both straits are for the most part more shallow than the Arctic Ocean, I would presume – particularly its central basins.

    I just don’t see how, absent significant changes in wind patterns or currents, you could get different sea levels in different places.

    It does seem rather strange, doesn’t it?

    But there is the Southern Oscillation, the Pacific Decadal Oscillation and the Arctic Oscillation, all of which are due to the interaction between the atmosphere and the ocean. Over large enough areas the interaction between the atmosphere (principally due to air pressure) and the ocean (e.g., water flow, temperature and salinity) is sufficiently strong to produce millimeters of rise and fall over time. In terms of the general principles, this sort of phenomena is fairly well understood, but the arctic is a little more remote – so we know less regarding its specifics at this point.

    Comment by Timothy Chase — 19 Jul 2007 @ 2:57 PM

  210. Re #197 James: “I just don’t see how, absent significant changes in wind patterns or currents, you could get different sea levels in different places.”

    Sorry, quite aside from tidal bulge, sea level is not globally homogeneous at any single point in time. See: http://www.flatrock.org.nz/topics/environment/poseidon_adventure.htm

    Comment by Jim Eager — 19 Jul 2007 @ 3:54 PM

  211. Jim, that John Daly page you refer people to is a decade old — from the Greening Earth Society.

    You might point to what’s been learned in the last ten years for updates.

    “… Few effects from global warming raise more red flags than rising sea levels. The topic has led to a growing pile of conflicting research trying to answer the questions: How fast, and why?

    “Now, a pair of US scientists conclude that the oceans rose at a global average rate of 1.5 to 2 millimeters a year (6 to 8 inches a century), confirming a hotly debated, decade-old estimate. But their work also points to the key driver of this change: water from melting glaciers and not, as some have argued, a natural swelling of the oceans caused by higher temperatures. …”
    http://www.csmonitor.com/2004/0325/p17s02-sten.html (2004)

    “Ice melt from small glaciers and ice caps will be the dominant cause of sea-level rise this century, according to new research. Scientists have previously suggested that the ice sheets of Antarctica and Greenland would be most responsible for rises as the Earth warms, as they hold the overwhelming majority of the world’s frozen water.

    Now an international team led by Mark Meier at the University of Colorado in Boulder, US, has found that glacial melt and the “calving” of icebergs into the ocean will account for 60% of all sea-level rise attributed to melting ice…” (July 2007)
    http://environment.newscientist.com/article/dn12295-melting-glaciers-will-dominate-sealevel-rise.html

    Comment by Hank Roberts — 19 Jul 2007 @ 5:38 PM

  212. Hank, read 163 where I first made the cite that satellite reading are modified by the tide gage trends to make the satellite readings more “accurate”.

    [edit]

    Please quit attributing where I get my cites from when I give you the cite. All your trying to do is make me out a denialist. I am a skeptic and have been presenting the things that make me skeptical, so please discuss the science and quit trying to paint me as something I am not.

    Comment by Vernon — 19 Jul 2007 @ 6:21 PM

  213. Re 211 Hank: “Jim, that John Daly page you refer people to is a decade old — from the Greening Earth Society.”

    I knew I shouldn’t have posted while in a hurry to get out the door. Should have waited until I had time to do a proper search. My bad.

    Comment by Jim Eager — 19 Jul 2007 @ 7:11 PM

  214. Re #205: [Do you know how deep the ocean is on either side of those connections, and how deep the basins are on either side?]

    Why should it matter how deep the basins are? This is liquid we’re talking about: it should spill over the edge of the basin, no?

    Please understand that I’m well aware of things like tides, variations due to winds and atmospheric pressure changes, and so forth. Let’s lump those all together and label them “sloshing around”. So after you account for all the sloshing around, how do you get long-term sea level varying from one place to another?

    Comment by James — 19 Jul 2007 @ 7:32 PM

  215. http://www.sciencemag.org/cgi/data/1143906/DC1/1

    Comment by Hank Roberts — 19 Jul 2007 @ 7:47 PM

  216. That’s OK, and in fact helpful — that Daly page _does_ talk about how they set up a network of island-based tide gauges, back when the satellite system was rolled out — and says they were using the tide gauges along with the first satellite results to figure out what they were getting.

    Perhaps the questions about using tide gauges to correct satellite results arise from reading that page about the early days. Just guessing of course.

    Comment by Hank Roberts — 19 Jul 2007 @ 8:12 PM

  217. It’s not just “liquid” — it’s a heat engine, the biggest one we have handy to study — multiple and changing variables, on a rotating and uneven sphere, in a varying gravity field, on an uneven bottom, interacting through vapor and ice transitions as well.

    It doesn’t just “slosh.” http://nasadaacs.eos.nasa.gov/articles/2005/2005_gravity.html
    You can certainly get a PhD answering even a few of the questions that would be answered before your big question was settled.

    Enjoy! http://sealevel.jpl.nasa.gov/science/time-series-data.html

    Comment by Hank Roberts — 19 Jul 2007 @ 11:26 PM

  218. [[In light of the discussion about sea levels i've recently come across a couple of mentions re Dr Nils Axel Morner from Sweden. He apparently withdrew from IPCC - here's a taster of what he claims "paleogeophysicist Nils-Axel M�¶rner, whoâ??s been studying and writing about sea levels for four decades, the scientists working for the IPCC have falsified data and destroyed evidence to incorrectly prove their point". ]]

    Well, you’ve always got your lunatic fringe.

    Comment by Barton Paul Levenson — 20 Jul 2007 @ 5:41 AM

  219. First of all, kudos to Hank for correctly writing “gauges” instead of “gages.”

    Sea level does, in fact, differ all over the world. Gravity is not the same from place to place and neither are currents, and both affect local sea level. Water flows, but that’s not the only factor involved.

    Comment by Barton Paul Levenson — 20 Jul 2007 @ 5:46 AM

  220. Re # 214 James’ question about sea level

    In addition to the factors mentioned by Hank and Barton, atmospheric pressure also affect sea level (a very localized example is the low pressure inside a hurricane that sucks up a mound of water that, when it reaches shore, esp. at high tide, creates a destructive storm surge).
    For a technical explanation of regional differences in sea level, see Chapter XIII, pages 458-469, and Chapter XV in The Oceans, by Sverdrup, Johnson, and Fleming ( http://ark.cdlib.org/ark:/13030/kt167nb66r ).

    Comment by Chuck Booth — 20 Jul 2007 @ 10:13 AM

  221. Beware other melting glaciers around the world (acc to a study mentioned in Reuters at http://www.climateark.org/shared/reader/welcome.aspx?linkid=80394 ).

    That’s what I’d been thinking…..what about all the other glaciers? I mean, if the warming is global…..

    But apparently they won’t amount to nearly as much sea rise as Antarctia or Greenland, once these get into serious melting — only about one foot (that also sounds like a low estimate for near complete melting of ALL other glaciers and snow packs of the world once it gets really hot enough to do that).

    So, given a high end BAU scenario and a warming of 5C by 2100-2200, and all sorts of positive feedbacks kicking in, when would all this glacier melt & sea expansion cause the sea to rise by, say, 20 meters, 60 meters, 100 meters? Might it be in 200 or 500 years (under a worse-case BAU scenario)?

    The article said we didn’t have to worry much this century, but that’s a cop-out. I’m concerned about the total extent of this warming, caused and/or triggered by our industrial soc GHG emissions, whether it goes on for 100 or 1,000 or 10,000 or 100,000 years. It’s about moral responsibility, not about getting some water in my house (which I did get in these recent S. TX floods).

    Comment by Lynn Vincentnathan — 20 Jul 2007 @ 11:17 AM

  222. Re sea levels: [Gravity is not the same from place to place..]

    But gravity in a sense defines “level”, doesn’t it? You’ve got the Earth, and if you take all the local variations in gravity, the centrifugal force from its rotation, the influence of lunar & solar gravity, and so on, you have a not-quite-spherical equipotential surface to use as a reference. If you didn’t have all that weather stuff, the sloshing, going on, liquid ought to follow that surface, no?

    (And yes, that surface is variable, as the positions of moon & sun change, and the liquid follows that changing surface, but the average stays the same.)

    [...and neither are currents, and both affect local sea level.]

    OK, now add in the sloshing. A current might raise the level here, depress it there, and the same for weather systems. But those are either going to be consistent, or they’re going to vary about some median value. If you have a gauge at some point, and filter out the sloshing so you just see long-term trends, you shouldn’t see a change unless there is a causative change in currents or weather. (Ignoring glacial melting &c for now.)

    So if Arctic sea levels are indeed decreasing, instead of the surrounding land rising due to glacial rebound, what’s the cause?

    Comment by James — 20 Jul 2007 @ 11:34 AM

  223. Agreed in general, and certainly the air pressure changes affect sea level variations in the Arctic Ocean. There’s a lot of published science on this. Just one example:

    “This study examines high-frequency sea level variabilities induced by surface pressure loading comparing with surface wind stress….
    In the Arctic Ocean, pressure induced component reaches more than 90 % of the variability forced both by pressure and wind. …. The average sea level delays since the basin-wide isostatic adjustment is only established by the limited water exchange through the strait. …..”
    http://www.agu.org/cgi-bin/wais?ee=OS25Q-01

    Note that Sverdrup et al. was published about 1942. They wrote “equatorial and polar radii are given in table 2, with other data concerning the size of the earth that can be computed from these values. The values for the equatorial and polar radii are those for sea level….. In the open ocean the deviations from the ideal sea level rarely exceed 1 or 2 m. The errors that are introduced by referring soundings to the actual sea surface are insignificant in deep water, where the errors of measurement are many times greater. …” That’s clearly wrong, as we know from the satellite work — the planet’s far lumpier than had been thought!

    Comment by Hank Roberts — 20 Jul 2007 @ 11:35 AM

  224. Re #214, “how do you get long-term sea level varying from one place to another?
    Try this FAQ, question 1: What is “Mean Sea Level?”

    http://www.pol.ac.uk/psmsl/puscience/#1

    Comment by Spilgard — 20 Jul 2007 @ 12:12 PM

  225. I saw this quote in Science Daily talking about glacial melting “While this is a dynamic, complex process and does not seem to be a direct result of climate warming, it is likely that climate acts as a trigger to set off this dramatic response,” said U-Boulder geology Professor Robert Anderson, study co-author. Also INSTAAR researcher. http://www.sciencedaily.com/releases/2007/07/070719143502.htm

    The IPCC Working Group One – “Physical Basis for Climate Change” thought glacial melt was caused by climate climate change. What gives?

    Comment by Jeanette Murry — 20 Jul 2007 @ 9:15 PM

  226. Jeanette, read that again, I think you misread the antecedent for the word “this” as meaning “glacial melting” but
    as I read it, his “this” refers to the stretching and sliding of the ice — the rate at which it moves, how much of it is supported by water, so how much it calves. That’s clearly not a “direct result” of “global warming” — you can chart the global temperature change and compare it to the rate of different glaciers and ice caps and they vary, so it has to be an _indirect_ relationship.

    What’s “direct” is probably something like water melting on the surface. By the time that gets to the base, and gets translated into movement, a lot of other variables have been involved. See if you read it that way. If we’re lucky, maybe he or one of the researchers involved can tell us what the meaning is supposed to be.

    ———-excerpt——–

    “Water controls how rapidly glaciers slide along their beds, said Anderson. When a glacier with its “toe in the water” thins, a larger fraction of its weight is supported by water and it slides faster and calves more ice into the ocean at the glacier terminus.

    “While this is a dynamic, complex process and does not seem to be a direct result of climate warming, it is likely that climate acts as a trigger to set off this dramatic response,” said Anderson.

    —– end excerpt ——

    So I’d say “this” dynamic complex process — how rapidly glaciers slide — is what’s triggered by climate. Look at the icequake rates and numbers in Greenland and Antarctica.

    Comment by Hank Roberts — 20 Jul 2007 @ 9:45 PM

  227. Jeanette Murry (#225) wrote:

    I saw this quote in Science Daily talking about glacial melting “While this is a dynamic, complex process and does not seem to be a direct result of climate warming, it is likely that climate acts as a trigger to set off this dramatic response,” said U-Boulder geology Professor Robert Anderson, study co-author. Also INSTAAR researcher. http://www.sciencedaily.com/releases/2007/07/070719143502.htm

    The IPCC Working Group One – “Physical Basis for Climate Change” thought glacial melt was caused by climate climate change. What gives?

    I would presume that they mean that in the case of each glacier, the process is complex involving numerous factors, including the unique history and geological setting of the glacier, where the history will include the specific weather that it has been subject to. In essence, this is the same principle behind not trying to attribute any given storm, flood, drought or hot summer day to global warming. As he and many others view it, global warming isn’t a particular entity like a storm, flood or drought. As such it cannot cause these things. Global warming, or rather climate change, is something more statistical in nature – which makes these sorts of things more probable.

    In the same way, you can’t speak of “human” as walking along the street, being a certain height or having a particular hair color, but you can speak of a particular human doing, being and having these things.

    Comment by Timothy Chase — 20 Jul 2007 @ 10:15 PM

  228. Re: Timothy Chase, Climate change is a gradual process that adds to the effects of natural climate variablity. Therefore in a way they are right for saying there is no ‘direct link’. Only over time can the big picture be fully appeciated by the dramatic rise in hurricane numbers and their intensity over the last 20 years..fact! The number of tornadoes and their intensity over 20yrs..fact!. The number of temp records broken all over the world..either high or low..fact! And photographic evidence of glacial melt in europe, the americas, greenland..etc..etc..fact! Each of these taken and analysed alone is insufficient evidence for drawing a direct correlation to climate change..but all these signs and climatic conditions taken together do indeed draw a very direct connection to climate change. Even blind Freddy would see the connection. I now understand why climatologists prefer the term ‘climate change’ over ‘greenhouse effect’, for the reason that it effects every part of the world differently. But what is true all over the world is that virtually every country’s usual weather patterns ate becomming very unstable and unpredicable. Cold snaps even more intense..heat waves last longer and are more severe. Thunderstorms are far more vicious and damaging, rain periods now cause widespead flooding far more regulary than in the past. Here in sunny queensland australia..after our hottest autumn on record..we are now having our coldest winter on record..many many records have been broken for extreme cold. This has caused one of our worst influensa outbreaks for decades.

    Comment by Lawrence Coleman — 21 Jul 2007 @ 2:49 AM

  229. James, oscillations? That doesn’t mean they’re like sine waves or clockwork, that means things that vary, and how they vary is part of what’s being studied. You read about the Arctic Oscillation, right?

    Read the caveats, then graph it here:
    http://www.cdc.noaa.gov/ClimateIndices/
    Try it again with a 12-month, a 60-month, and a 120-month running mean. Does it go up and down? See a trend?

    > If you have a gauge at some point, and filter out the sloshing so you just see long-term trends
    But “if” isn’t a data set — what gauge would you look at? The ones in the record?

    The ones referred to in previous postings are mostly along the coastline of Russia.

    If you read the studies already cited and followed the links you know as much as has been published.

    Did you read Proshutinsky et al.? Note the dates

    “… sea level change is the net result of many individual effects of environmental forcing. Since some of these effects may offset
    others, the cause of the sea level response to climate change remains somewhat uncertain. This paper is focused on an attempt to provide first-order answers to two questions, namely, what is the rate of sea level change in the Arctic Ocean, and furthermore, what is the role of each of the individual contributing factors to observed Arctic Ocean sea level change? In seeking answers to these questions we have discovered that during the period 1954 – ­1989 the observed sea level over the Russian sector of the Arctic Ocean is rising …. There are two major causes of this rise. The first is associated with the steric effect of ocean expansion…. The second most important factor is related to the ongoing decrease of sea level atmospheric pressure over the Arctic Ocean… A third contribution to the sea level increase involves wind action and the increase of cyclonic winds over the Arctic Ocean …. The combined effect of the sea level rise due to an increase of river runoff and the sea level fall due to a negative trend in precipitation minus evaporation over the ocean is close to 0…..”

    Got that? Now, look back at the Arctic Oscillation graph you made —— look at it with the 120-month average. Look like it fits?
    Maybe. Just guessing here. You can probably do better, if you have the time to study it.

    Comment by Hank Roberts — 21 Jul 2007 @ 5:56 AM

  230. Make that running mean an odd number, by the way; read the caveats _and_ the notes on the page!

    Comment by Hank Roberts — 21 Jul 2007 @ 5:58 AM

  231. Lawrence Coleman (#228) wrote:

    Re: Timothy Chase, Climate change is a gradual process that adds to the effects of natural climate variablity. Therefore in a way they are right for saying there is no ‘direct link’. Only over time can the big picture be fully appeciated by the dramatic rise in hurricane numbers and their intensity over the last 20 years..fact!…

    I wasn’t agreeing or disagreeing.

    In fact, given the logic of what I stated it seems unavoidable. But I was stating it without stating that it is something that I agree with or disagree with – because I can understand the frustration someone might experience over not being able to say that, “Global warming is the cause of the decline of our glaciers,” direct or not. Additionally, one can argue in any particular case in which one can distinguish between cause and effect that the cause is not “the cause of the effect” but merely contributes to it. In a sense, this is true – but largely philosophical in nature. People ordinarily don’t think like that – and will omit various factors from their analysis. At a certain level, we have to simply in order to be able to act in the world.

    However, thank you for bringing up the gradual nature of the process. It makes the original argument stronger.

    Comment by Timothy Chase — 21 Jul 2007 @ 11:14 AM

  232. Re 228: Lawrence, how is the water situation in the Murray-Darling basin? The new favorite “expert” of the contrarian camp, 15 yr old Kirsten Byrnes had predicted its end and I read somewhere that farmers have planted a lot of crops in anticipation of winter rains. However, it seems that the prime minister has already mentioned the possibility of shutting off all irrigation to preserve drinking water.

    Comment by Philippe Chantreau — 21 Jul 2007 @ 12:07 PM

  233. Can anyone explain how the air pressure over the Arctic sea is dropping (which should raise sea levels) yet the sea levels in the Arctic sea are actually dropping?

    This does imply that the actually amount that the sea levels are dropping would be greater than actually measured.

    This lead me to start looking for correlations between barometric readings and measured sea levels. I ask this because barometric pressure will affect sea levels and I was wondering how this was adjusted for. I saw with satellite readings they adjust for travel time due but not where they adjust the measured sea level based on the perceived air density. With tide gauges I would expect it to be worse historically.

    So does anyone know where to find a paper that shows the correlation between apparent sea level measurements and actual in reference to barometric pressure?

    Comment by Vernon — 24 Jul 2007 @ 10:38 AM

  234. Unfortunately only a relatively small part of the available Arctic ocean weather and climate data is unclassified (that from the so-called “Gore Box”– Al Gore got the Navy to declassify an area back when he was vice president).

    Most of the work that’s come out of that can be found searching for thesis papers at the Navy’s post-graduate school website (Monterey CA). I’ve pointed to it previously, but they do keep rearranging their pages so none of the old links work. Searching will find it.

    Other than that, there are compliations, searching comes up with some:

    Try these, tell us what you find if you read them?
    icoads.noaa.gov/climar2/climar2_oral_final.pdf
    http://www.olympus.net/IAPSO/GeneralAssembly99/P13/P13full.htm
    https://kb.osu.edu/dspace/bitstream/1811/6050/1/BensonFinalTranscript.pdf.
    http://www.oceans2025.org/pdfs/Oceans%202025%20-%20Theme%2010%20open%20(rev).pdf

    Comment by Hank Roberts — 24 Jul 2007 @ 1:04 PM

  235. And I pasted your question into Google Scholar’s search box, which yielded some papers discussing this. But again we’re rather far off the Greenland Ice thread’s purpose. May I suggest you try the Friday Roundup topic to pursue the more general questions?
    http://www.jisao.washington.edu/wallace/sotrends121803.pdf
    http://www.agu.org/pubs/crossref/1997/96JC02920.shtml

    Meanwhile, back ON topic — I just finished Ward’s “Under a Green Sky” and take his point that what’s correlated with previous great extinction events was not a halt of the deep ocean transport but rather a rearrangement of it to where it carries warmer, less oxygenated water into the deep, leading to anoxic conditions. He does make his point clear that he’s more or less shouting across the gap between paleontology (focused on deep time) and climatology (focused on since-the-last-glaciation) and flagging for the climatologists the concern that the deep ocean circulation can simply move a bit sideways and cause a very profound change in oxygenation of the deep. He notes the lag between writing and publication, and doesn’t have the latest news about melting of small high glaciers’ contribution — which puts fresh water into a different area than melting of Greenland. I hope he’s reading this and can comment more.

    It’s a serious, small, very focused, very readable book. I recommend it highly, to those who want to go on this topic about Greenland’s ice. http://www.powells.com/review/2007_06_09.html

    Comment by Hank Roberts — 24 Jul 2007 @ 2:29 PM

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