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The IPCC is not infallible (shock!)

Filed under: — group @ 19 January 2010 - (Italian)

Like all human endeavours, the IPCC is not perfect. Despite the enormous efforts devoted to producing its reports with the multiple levels of peer review, some errors will sneak through. Most of these will be minor and inconsequential, but sometimes they might be more substantive. As many people are aware (and as John Nieslen-Gammon outlined in a post last month and Rick Piltz goes over today), there is a statement in the second volume of the IPCC (WG2), concerning the rate at which Himalayan glaciers are receding that is not correct and not properly referenced.

The statement, in a chapter on climate impacts in Asia, was that the likelihood of the Himalayan glaciers “disappearing by the year 2035” was “very high” if the Earth keeps warming at the current rate (WG 2, Ch. 10, p493), and was referenced to a World Wildlife Fund 2005 report. Examining the drafts and comments (available here), indicates that the statement was barely commented in the reviews, and that the WWF (2005) reference seems to have been a last minute addition (it does not appear in the First- or Second- Order Drafts). This claim did not make it into the summary for policy makers, nor the overall synthesis report, and so cannot be described as a ‘central claim’ of the IPCC. However, the statement has had some press attention since the report particularly in the Indian press, at least according to Google News, even though it was not familiar to us before last month.

It is therefore obvious that this error should be corrected (via some kind of corrigendum to the WG2 report perhaps), but it is important to realise that this doesn’t mean that Himalayan glaciers are doing just fine. They aren’t, and there may be serious consequences for water resources as the retreat continues. See also this review paper (Ren et al, 2006) on a subset of these glaciers.

East Rongbuk glacier 1921 and 2008East Rongbuk glacier just below Mt. Everest has lost 3-400 ft of ice in this area since 1921.

More generally, peer-review works to make the IPCC reports credible because many different eyes with different perspectives and knowledge look over the same text. This tends to make the resulting product reflect more than just the opinion of a single author. In this case, it appears that not enough people with relevant experience saw this text, or if they saw it, did not comment publicly. This might be related to the fact that this text was in the Working Group 2 report on impacts, which does not get the same amount of attention from the physical science community than does the higher profile WG 1 report (which is what people associated with RC generally look at). In WG1, the statements about continued glacier retreat are much more general and the rules on citation of non-peer reviewed literature was much more closely adhered to. However, in general, the science of climate impacts is less clear than the physical basis for climate change, and the literature is thinner, so there is necessarily more ambiguity in WG 2 statements.

In future reports (and the organisation for AR5 in 2013 is now underway), extra efforts will be needed to make sure that the links between WG1 and the other two reports are stronger, and that the physical science community should be encouraged to be more active in the other groups.

In summary, the measure of an organisation is not determined by the mere existence of errors, but in how it deals with them when they crop up. The current discussion about Himalayan glaciers is therefore a good opportunity for the IPCC to further improve their procedures and think more about what the IPCC should be doing in the times between the main reports.

Update: This backgrounder presented by Kargel et al AGU this December is the best summary of the current state of the Himalayas and the various sources of misinformation that are floating around. It covers this issue, the Raina report and the recent Lau et al paper.

1,804 Responses to “The IPCC is not infallible (shock!)”

  1. 351
    Ray Ladbury says:

    Tom, I might agree if the models were the only weapon in the climate science arsenal, but this is simply not true. There are paleoclimatic studies, phenological studies, satellite measurements, ocean measurement and even atomic and molecular studies. The reason you don’t see as much of the latter is because the properties of the molecules and gasses have been understood since the ’50s.

    In essence, the denialists are asking us to forget about a century of studies that support the model development and do it all over again with them watching. [edit] Go look it up in 50 year old Phys. Rev. volumes!

  2. 352
    Rod B says:

    Doug Bostrom (287), I guess if you can instruct mircea on models I can help you with model assessment. The point was that riding on airplanes required a lot more than simple high confidence in the models, as opposed to what has been asserted here numerous times. You’re saying however, currently, models do a pretty good job by themselves. 1) they are still not the lone validator by a long shot. 2) They’re good today because of mucho updates and revisions that came from physical verifications and reiterations. Saying we ought to accept climate models on faith just because we board airplanes with no thought — (well even that isn’t fully true) — is pure hand waving.

  3. 353
    Completely Fed Up says:

    “Apparently they send a different kind of electrons that cost more to generate to rich folk.”

    More reasonably explained by electricity is a life requirement.

    Therefore pricing even 5% of your population out of the market is untenable.

    Quite a common idea in the civilised world: public healthcare.

    The US has an extremely vocal minority who believe (whenever convenient: they won’t remove Medicare, armed forces or emergency cervices from government (mis)management) that anything the government does is done badly.

  4. 354
    Tom says:

    @347 – I never even suggested it was ok to make stuff up (much the opposite) or said scientists did this. Throwing out straw men and waiting for me to defend them is also an unbecoming argumentative style. I understand the primary function of this site is arguing the science, but that doesn’t mean comments cannot reply to the argumentative style of other comments. If it did, much of your commentary would be wildly off point. Indeed, the kind of knee jerk embattlement and refusal to see subltety encoded in your response to someone who is actually on your side in a greater scheme of things seems again as irrational as denialism. I really don’t see why advocating maintaining an argumentative high ground meets such hostility from some of the very people for whom this is supposed to be the raison d’etre! I don’t think just because people choose the “right side” they get carte blanche. The wrong teammates can discredit one’s own side unfairly.

  5. 355
    Completely Fed Up says:

    “So back to the point, whether generation costs charged to customers is $.05 or $.08 per kWhr, that is a lot less than the rate paid to wind and solar producers, even at the lowest of these rates.”

    That’s much much less than it costs the nuclear industry spends to create their energy. How are they managing to make money if you pay 1/4 the cost of the electricity, Jim?

  6. 356
    Mal Adapted says:

    Bushy:

    I firmly believe that at our current level of understanding we have no basis for making the claim that AGW is real or even that it poses a threat of any kind.

    I’m sorry, but I can’t resist using Hank’s masterful riposte from a previous thread:

    “unless you have parasites, this is overplurification.”

    Bushy, at your level of understanding, you obviously have no basis for claiming that the sun will rise tomorrow. The RealClimate scientists who post here regularly have much greater understanding than you do.

  7. 357
    Matthew L. says:

    # CFU
    “Let us charitably say that you’ve forgotten that this land isn’t being used for generating wind power”

    Exactly! I was calculating the “energy generation density”, not the land’s ability to produce sheep or cabbages. The space between the turbines cannot be used for generating wind power because it is too close to another turbine. Therefore the wind power “energy generation density” of the land (with these particular turbines) is 77 watts per square metre – at best.

    Of course the total productive capacity of the land could be calculated if you like, but this is a site discussing the role of carbon dioxide from industry (such as power production) in causing climate change. It is not concerned with agricultural productivity.

    As somebody else here stated, no farmer is going to let an energy company plonk one of these monsters on his land for nothing. He will either ask them to buy the land or extract a hefty rent payment off them.

    It is not me that you need to convince of the economics of on shore wind power, it is Gordon Brown and the British Labour Party who are proposing to use my tax money to heavily subsidise the construction of massive offshore wind farms. Personally I would be quite happy to see more windmills on land but unfortunately most of those making the actual decisions clearly aren’t.

    As for the solar power idea, have you experienced a summer in the UK?
    Clearly not! ;-)

  8. 358
    mircea says:

    Doug Bostrom says 22 January 2010 @ 12:35 AM

    There is no certification or validation based on simulations or models. The A/C has to be certified once ready (the first flight is the start of certification). The models/simulations are used only for design/orientation but the validation/confirmation comes only from real measurements.
    When the A/C is ready for flight actually only the flight model was not validated by measurements (all the other system models – engines, flight controls, avionics – are measured on the real aircraft part. And even the flight model has actually been validated on other A/C (B777 or B737).

  9. 359
    mircea says:

    Nick Gotts says at 22 January 2010 @ 6:18 AM

    “I’m interested to know how a scale model of a plane lets you test for several decades of use, bird strike, failure of one or more engines, take-off and landing in poor weather, etc, etc.”
    For example they take the real engine and they shoot birds in it (they are dead) and examine the damage. The model is used in air tunnels to measure the forces (but this is only for initial design stage and it’s not for validation).
    All the malfunctions are checked and validated on the real a/c in real situations when possible.

  10. 360
    Mal Adapted says:

    Tom S.:

    Science is great at explaining why things happened, but not so great at predicting the future.

    As I’ve observed elsewhere, Science can not only explain why things happened, but can often predict with a high degree of certainty what will happen in the future. The problem is that Science can’t tell us why we should care.

    I’m convinced that large numbers of people think AGW will affect only other people, not anyone they care about. “Me and my wife, son John and his wife, us four and no more.” As for future generations, well, “What have future generations ever done for me?”

    I have little hope that better communication will turn that around.

  11. 361
    Didactylos says:

    Completely Fed Up:

    That’s an ideal power density. It bears no relationship to what can be actually extracted by wind farms built today. Can you imagine what a 100% efficient wind farm would be like? o_O

    David MacKay calculates 2 W/m², which is confirmed by actual power output from existing wind farms.

    As Gavin says: find some actual sources of data! (Then understand them.) I have already provided you with my sources, I see no need to repeat them again and again.

  12. 362
    Rod B says:

    Ray (326), are you then confirming that 28% of the outer shell or envelope is He?? I said it is not; you seem to say it is because it is not made of Fe. I can’t follow the chemical logic of that.

  13. 363
    Tom S says:

    OK, I looked at some of the modeling articles around. Obviously things are very complex, and the deeper you go, the more complex it gets. The more you know, the more things you know that you don’t know.

    I wouldn’t be here if I wasn’t trying to reduce my uncertainty.

    It looks like there has been some progress in modeling. I guess the thing that bothers me the most is the temperature reversals and their causes. The pause during the 1950 time frame is thought to be aerosols.

    1. Do the climate models predict eventual future temperature reversals such as MWP or little ice age? Do they agree?

    2. The models look to diverge a fair amount in the 100 year period. What is the leading factor in this difference? Parametrization settings?

    3. Why do the models not diverge much in the past if they are diverging more in the future? If it physics based, this doesn’t seem to make sense.

    3. Are there not compensating factors on the Earth that kick in and balance changes such as CO2 changes? Cloud cover, snow area, whatever? What is the expected reversing mechanism for the current temp increase?

    4. What is the leading parameter / prediction of the climate models I can check to see how well they are performing without waiting for 30 years? Is it just temperature, or is there some other major parameter, gulf stream, etc. that is a leading indicator?

    5. If there is global warming, why is it so cold in Florida this winter? (just kidding).

  14. 364
    Doug Bostrom says:

    TCO says: 21 January 2010 at 11:46 PM

    “The initial response by IPCC and Pauchari was to double down and to stick with the statement.”

    You say. Another interpretation: the IPCC did not consider this single paragraph in an ancillary portion of the report to be a significant problem and thus ignored it. Belatedly, they realized that intellectual desperadoes out of real bullets would seize upon it, exaggerate it as a “central claim” and then spoon feed it to gullible journalists.

    Tom S says: 22 January 2010 at 8:52 AM

    “The fundamental problem that is faced is one of validation, nobody knows whether it is accurate or not for 25+ years.”

    Tom, before you take this too far, you really owe it to yourself to read the developmental history of climate models. If you do, you’ll find out that while they still have “issues”, there have been some very interesting cases of validation emerging even from desperate attempts to get the models to match erroneous paleoclimate assumptions. In other words, modelers attempted to force models to replicate mistakenly created paleoclimate signals, eventually discovered the models were vindicated when it turned out the models were sufficiently robust as to be unable to “lie”, the paleoclimate interpretation being found wrong.

    Read here:

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

  15. 365
    Didactylos says:

    “The base may only take up, say 10m x 10m but the rotor has a diameter of 126m.”

    “Completely Fed Up” said: “Please tell me how many crops crow 100ft high.”

    You have entirely missed Matthew L.’s point. Spectacularly, in fact!

    Although, the thought of enormous wind turbines packed so closely together that they can’t rotate to face the wind, and risk the blades colliding with every sway they make – now, that might get somewhere close to the 100% efficient wind farm I mentioned! Or it might not generate any power at all…. something that behaves like a solid wall doesn’t, typically.

    Read. Learn: http://www.inference.phy.cam.ac.uk/withouthotair/cB/page_263.shtml

    I know I have already provided you with this source, but perhaps you didn’t make it all the way to the technical chapters.

    Notice that our answer does not depend on the diameter of the windmill … because bigger windmills have to be spaced further apart. Bigger windmills might be a good idea in order to catch bigger windspeeds that exist higher up (the taller a windmill is, the bigger the wind speed it encounters), or because of economies of scale, but those are the only reasons for preferring big windmills.

  16. 366
    Septic Matthew says:

    This is way too much writing about something that could have been simply handled from the start. When there is a claim of error in the IPCC science, IPCC should:

    1. investigate the claim by reviewing published literature on the topic;
    2. when there is an actual error, as in this case, acknowledge the error and thank the person who found it;
    3. publish the corrigendum in case of a mistake, and publish the rebuttal when the claim of a mistake is itself a mistake.

    Everybody makes mistakes, and everybody knows that everybody makes mistakes. What’s fuel for the denialists is the IPPC’s attempt to disparage its critics. If IPCC is going to claim that all of its scientific information is from peer-reviewed literature, then it needs to be sure that the claim is true.

  17. 367
    oliver conway says:

    In a hypothetical scenario, none of my denier acquaintances are prepared to spend any time in a sealed garage in which a cars engine has been running for 30 minutes at 2000 rpm. In that amount of time a 2.5 liter engine will consume the entire volume of breathable air in the garage. With a billion internal combustion engines now operating on the planet, according to my admittedly non scientific calculations, the entire volume of breathable air in our atmosphere is ‘processed’ 4 times every year.
    Are we as a species insane, or what?

  18. 368
    R.S.Brown says:

    Although this “backgrounder” mentions the Rania “discussion paper”, none of the citations supporting the
    “backgrounder”. It doesn’t answer any of the many points in the Rania work.

  19. 369
    Svet says:

    Gavin’s response to #335
    Gavin, you say “But there is longer term validation data available”. Fair enough, but there is a big difference between being consistent with the past and successfully predicting the future. As Tom S said “It would be encouraging if the current models followed the flattening of the past 10 years.” I think in the past you have explained the current flattening as being natural variation that cannot be modeled. As a laymen, I find this explanation troubling because it raises the obvious question “Could much of the warming since say 1980 also be due to natural variation that cannot be modeled?”

    [Response: Where did I ever say natural variation cannot be modelled? It is modelled all the time, and is the principle reason why individual model simulations have such a range of values for the short term trends. It is however hard to predict, which is not the same thing at all. There is no evidence that the long term trends can be accounted for by natural variation – and plenty of evidence that they are driven (mainly by greenhouse gases). – gavin]

  20. 370
    Jimbo says:

    I have notice something.
    Since my posting at comment no. 6 — 19 January 2010 @ 5:45 PM nobody has rebutted the quotes made in the links. Why is this so? Is it because the “soot nonsense” comes from NASA?

    Is it because the BBC reports:
    “Others who have observed nearby mountain ranges even found that glaciers there were advancing.”

    Instead some people have chosen to attack me. Why? I suggest that you attack the statements from the organisations who have made those contrary statements. Please do so. Don’t attack the messenger attack the message.

    I was hoping for a response from Gavin but alas he works for NAS?

  21. 371
    PB says:

    >>>>>
    Let us charitably say that you’ve forgotten that this land isn’t being used for generating wind power, so you can, say, grow crops or feed cattle on it.

    Or, indeed, generate solar power.
    >>>>>>

    How about some of each? :-)

    BTW,
    In your running discussion, you guys have missed (or it’s buried in your references, apologies if I missed it) the differences in “Feed-In Laws” for different locations. In a number of European countries, the power utilities are commanded to prioritize dispatch to wind, solar, hydro, nuclear, etc. before fossil fuel powered sources. This way, the power provider can get immediate return on his/her turbine, solar array, hydro dam, or nuclear station before the coal/oil/gas fired plant goes online.

  22. 372
    Doug Bostrom says:

    Jim Bullis, Miastrada Co. says: 22 January 2010 at 11:35 AM

    et al, many posts…

    Something to consider in these comparisons are external costs, intractable for quantifying right now due to many unknowns but undoubtedly real (kind of like gravitation, pre-Newton etc.?)

    My point being, comparing the cost of power produced by generation plants emitting C02 with other sources based on the present, visible dollar input per kilowatt generated ignores that we’re actually borrowing money to produce the electricity from C02 emitting systems to yield the present seeming cost.

    I don’t think it’s really in dispute that we’re going to face some degree of cost in the future while engineering our way around the C02 we’re releasing now. That’s not reflected in the rate structure of most utilities; the present day rates are subsidized with future dollars.

    Just a caveat. I have no idea how to assign numbers to what I’m speaking of, although I’m confident there are unaccounted costs.

  23. 373

    Did: If wind were the panacea you seem to think, then we would be there already.

    BPL: Here is the % of new electrical generating capacity in the US represented by wind the last several years:

    2004 4%
    2005 12%
    2006 19%
    2007 35%
    2008 42%

    If I were you, I’d invest.

  24. 374

    Thanks for getting my back, Ray! :)

  25. 375
    Svet says:

    Gavin’s response to #353
    You are right – I should have said something like “an aspect of natural variation that hadn’t yet been modelled”. However, my real point is that it is much, much more convincing to be able to predict the future than to simply be consistent with the past. If your model could consistently predict the future then it would be truly convincing. It would constitute (at least in my layman’s mind) proof of AGW. If it doesn’t consistently predict the future then it only demonstrates the plausability of AGW but would not constitute proof.

  26. 376

    Tom S: It is just not credible to me that these models are reliably accurate without ever been validated.

    BPL: http://BartonPaulLevenson.com/ModelsReliable.html

  27. 377
    Doug Bostrom says:

    Rod B says: 22 January 2010 at 12:11 PM

    Rod, not so much instructing as reporting what I have on first hand account from a good friend who is a senior engineer at Boeing’s sim lab, presently engaged w/the 787.

    “Saying we ought to accept climate models on faith just because we board airplanes with no thought — (well even that isn’t fully true) — is pure hand waving.”

    Fortunately that’s not my point. Anyway, for something more germane to the topic at hand, see http://www.aip.org/history/climate/GCM.htm

    mircea says: 22 January 2010 at 12:32 PM

    You don’t seem to be disagreeing with me. Specifically, what is it about the models– airplane or climate, your choice– that you find lacking? Anyway, your initial analogy was poorly chosen and ultimately irrelevant. See the AIP link above to learn more.

  28. 378

    Matthew L: As for the solar power idea, have you experienced a summer in the UK?
    Clearly not! ;-)

    BPL: My father was stationed in London during WWII. He says when he was there, summer was on a Wednesday.

  29. 379
    Completely Fed Up says:

    “it is much, much more convincing to be able to predict the future than to simply be consistent with the past. If your model could consistently predict the future then it would be truly convincing”

    Be convinced, then:

    http://www.realclimate.org/index.php/archives/2009/12/updates-to-model-data-comparisons/

  30. 380

    Rod B: Ray (326), are you then confirming that 28% of the outer shell or envelope is He?? I said it is not; you seem to say it is because it is not made of Fe. I can’t follow the chemical logic of that.

    BPL: You may be confused by books which list it as 93% hydrogen and 7% helium. My (and Ray’s) figures are by mass; the other are by volume–remember that a helium nucleus is four times as massive as a hydrogen nucleus.

  31. 381
    Completely Fed Up says:

    “You have entirely missed Matthew L.’s point. Spectacularly, in fact!”

    Well lets see if you can elucidate, shall we?

    “Although, the thought of enormous wind turbines packed so closely together that they can’t rotate to face the wind,…”

    Ah, seems that you can’t.

    No, the proposition that the cost of wind is huge because land is scarce and needs to be used for growing food for example rather requires that all the land occupied by a wind farm can only be used for one purpose: the wind farm.

    Unfortunately, this is not true.

    You seem to have missed MY point and spectacularly and consistently.

    You can use that land for farming and 0.1% generate wind.

    At 70kW/m2 a 0.1% occupancy would leave you with 70W/m2 and cost you £2 in land costs compared to your £2000.

    And reducing your farming capacity by 0.1%.

    Negligible.

    Your arguments are so easily falsifiable why do you bother to make them?

  32. 382
    Completely Fed Up says:

    “It bears no relationship to what can be actually extracted by wind farms built today. Can you imagine what a 100% efficient wind farm would be like?”

    Yes: it would produce about 3x the rated power output in the sales brochures.

    It would produce that power using ~0.2% of the land the wind farm “occupies” in your sense.

    More land is wasted at the edges of the land to allow the harvester to turn around…

  33. 383
    Completely Fed Up says:

    “For example they take the real engine and they shoot birds in it (they are dead) and examine the damage. ”

    Remembering to defrost the chicken.

    But when you make your scale model, the viscosity is not the same and the depth of the “skin” where the air reduces speed is relatively thicker.

    This is why small models of water inundations with water look like small models: the water still produces the same size droplets and to scale, those droplets are HUGE.

    Yet you assume these are adequate why?

  34. 384
    Svet says:

    Gavin’s response to #369
    You said “There is no evidence that the long term trends can be accounted for by natural variation – and plenty of evidence that they are driven (mainly by greenhouse gases)”. I know that this is a naive question but is it possible to list in brief dot point form what the proofs of AGW that you refer to are? I don’t think that I have every seen such a list. Not at RealClimate and not even in the IPCC FAR.

    [Response: Read Chapter 9. It goes over it in excruciating detail. – gavin]

  35. 385
    Completely Fed Up says:

    Matt: “Exactly! I was calculating the “energy generation density”, not the land’s ability to produce sheep or cabbages”

    But the land can do both.

    Where you could before produce, say (for arguments sake) £30,000 of cabbages you can plant four turbines of 7MW output, lose 4x10x10m area and reduce your cabbage selling capabilities (which were sufficient to allow you to buy and use the land) by £30.

    Cabbage reduction to £29,970.

    All you have to do is sell 4x365x24x7000 kWh units of electricity for £30 and you’ve broke even.

    Do you think they can sell wind power electricity for 1.2×10-5p per kWh?

    I think they can.

  36. 386
    Completely Fed Up says:

    “BPL: My father was stationed in London during WWII. He says when he was there, summer was on a Wednesday.”

    Which Wednesday???

  37. 387
    Hank Roberts says:

    Tom S., you’re asking questions that are in the FAQs and Spencer Weart’s book.
    People will give you answers, but you can do better than getting answers typed from memory in blog posts by people you don’t know–by reading some of what’s behind the Start Here button at the top.
    Otherwise you get partial answers that will raise more questions that are _also_ in the FAQs.
    This abstract may help: http://ams.confex.com/ams/Annual2006/techprogram/paper_100737.htm
    That gives search terms you can use to find the documentation in the FAQs for the basic points.

  38. 388
    Hank Roberts says:

    > Comment by Jimbo — 19 January 2010 @ 5:45 PM
    Speaking just as another reader here, not an expert — I suspect nobody replied to what you posted because there’s nothing there needing a reply. You did very selective quoting, people expect that to happen. But you did provide the links to the original sources — thank you! That’s good behavior, and given the links people can read the originals.

    Once I looked at the originals, I can see you picked out the bits you quoted from articles that made good sense, and explained things clearly. You can too, I think. Point is, if you came here thinking people believe it’s only CO2, for example, that’s a misapprehension. Nothing in those articles is surprising or contradicts anyone’s certainty. It’s interesting science.

    Key term may be “rate of change” — as your last link says, they had one brief hot summer and extreme melting in 1947, and that’s weather; they comment that now we are having _decades_ of warming, which is a more serious problem; that’s climate change.

  39. 389
    Doug Bostrom says:

    Jimbo says: 22 January 2010 at 3:26 PM

    “Since my posting at comment no. 6 — 19 January 2010 @ 5:45 PM nobody has rebutted the quotes made in the links. Why is this so?”

    I think it’s because you have not taken the time to explain in any degree of detail how these quotes are relevant and to what degree they are significant.

    Sometimes folks are just too exhausted or bored to respond to “what about this”, especially if “this” is old news.

    Maybe you should redo the post, add a paragraph to each demonstrating how and why each item is important enough to warrant a response?

  40. 390

    Jimbo: I was hoping for a response from Gavin but alas he works for NAS?

    BPL: Yes, he’s a member of the conspiracy. We were going through the security check at the airport a year or so ago and I noticed when he opened his wallet that Gavin, like me, had a World Jewish Conspiracy ID card. We even reported to the same Commissar!

    [Response: Shhhhh…. ! – gavin]

  41. 391
    David B. Benson says:

    Russell (269) — (1) Tung & co-workers determine about 0.17 K variation over the average sunspot cycle, but this might well be too high. In any case, ocean oscillations, principally ENSO, tend to bury that minor solar forcing.

    (2) Averaging effects in measurements always have to be taken into consideration. With regard to CO2 cocentrations one would, however, have to posit a major source of excess CO2; there hasn’t been such in the last 650,000 years except for the recent burning of fossil fuels and deforestation.

    (3) All excess CO2 is indeed due to human activities, which began to influence climate long before 1850 CE. Please read climatologist W.F. Ruddiman’s popular “Plows, Plagues and Petroleum” as well as hig guest thread here on RealClimate.

  42. 392
    Svet says:

    “Read Chapter 9. It goes over it in excruciating detail”. OK but the “excruciating detail” is the problem. Telling a layman to read Chapter 9 is kind of a cop out. Isn’t RealClimate supposed to make the science more accessible? I have been following the topic of AGW off and on for several years now but I don’t think that I have ever seen a brief listing of the main “proofs”. It should be simple. Very frustrating.

  43. 393
    Ray Ladbury says:

    BPL: “Thanks for getting my back, Ray! :)”

    Given the degree to which you’ve surpassed us in documenting evidence, your back was all I could cover! ;-)

  44. 394
    Ray Ladbury says:

    Svet, Jim Hansen’s model predicted that each of the succeeding decades in the foreseeable future would be warmer than the last. Would I have to win every hand of Blackj-ack for the eyes in the sky to be convinced I fit their counting-c-ards model?

  45. 395
    flxible says:

    I don’t think it’s really in dispute that we’re going to face some degree of cost in the future while engineering our way around the C02 we’re releasing now. That’s not reflected in the rate structure of most utilities; the present day rates are subsidized with future dollars.
    Exactly what the fight is all about, nobody really wants to foot the bill for the petrosaurs massive historical profit taking. Hence all the hand waving about the “trillions” it’ll cost to fix things

    And all this hoorah over the cost of wind power vs anything else is ignoring the fact that the cost of energy in the future, no matter it’s form, will NEVER be less than what you’re paying at present – the economy we’re saddled with doesn’t work that way, the most important growth in society is the growth of profits.

  46. 396
    Ray Ladbury says:

    Jimbo@370
    Maybe it’s because the fact that other forcings might play a role in glacial melt is uncontroversial and has been noted here many times before and because a BBC report of hearsay evidence is not particularly noteworthy and because a study looking at a single decade in a single locale is not particularly notable on a global scale.

    No, none of these things is remarkable. What is ludicrous is your attempt to spin these facts to suggest that the climate somehow is not changing due to human activity. See in science, we don’t dispute facts. We dispute nutjobs who distort facts.

    What is also notable is that glaciers seem to be melting in Glacier, Montana and New Zealand (antipodes) and the Himmalayas and the Andes (roughly antipodes). Also Greenland, Alaska, and just about wherever else you find glaciers except inland at the South pole. Did you notice that it was called GLOBAL warming?

  47. 397
    Tom S says:

    OFF ON A TANGENT AND BABBLING
    I certainly confess to be an admitted skeptic ready for a 12 step program (Hi Tom!). I have found some answers to the questions I asked and I know they have certainly been brought up before in other threads. So I appreciate the pointers. My preconceived ideological positions may not change, but I do want to know and understand the AGW facts from both sides.

    There are many levels of winning a debate, preponderance of the evidence, clear and convincing, beyond the shadow of a doubt.

    AGW certainly requires additional research funding and an ongoing development of prediction models. It is deserving and you have proved that point (global warming is occurring, is a threat, and needs to be better understood). I am not in (total) denial.

    The issue of governance though is there are many deserving causes to balance. Do I spend my tax money on this, or Haiti, or AIDS research, or Cancer research, or third world curable diseases, or buy a new stereo?

    These are all obviously deserving and competing causes. The biggest obstacle is others causes have immediate and undoubted ill effects. AGW is a maybe, or a probably, and demands huge sums of money to avert. Save us now, or save us later. It seems prudent to put AGW on a wait and see while funding more immediate problems at higher level.

    Just babbling, not trying to open a huge debate here.

  48. 398
    flxible says:

    Jimbo, 370&6
    Likely nobody responded because the questions and quotes weren’t too compelling – I don’t work for NASA, nor am I a scientist, but do live below a glacier, so I’ll take a run at it, someone may correct me: [bolding mine]

    I always thought that as they melt they release water for people, plants and animals downstream
    Very true, at certain times of the year, and usually that’s at the end of the warm season, when other precip is less. I don’t think a glacier that’s actually increasing mass would be supplying as much melt water as folks below were accustomed to, nor conversely would they be too happy if melting continued into the rainy season, or if the retreating glaciers resulted in the newly exposed till being swept downstream by the monsoons. Glaciers are useful to buffer the water supply over time.

    “In fact, the new research, by NASA’s William Lau and collaborators, reinforces with detailed numerical analysis what earlier studies suggest: that soot and dust contribute as much (or more) to atmospheric warming in the Himalayas as greenhouse gases.”
    Exactly – glacial melt may be exacerbated by albedo conditions, which doesn’t mean GHGs aren’t as [or more] important generally, just that soot is an important contributing factor in this particluar situation [glacial melt]. The contribution of soot/dust isn’t a new finding, it’s been confirmed yet again.

    “Based on the differences it’s not difficult to conclude that greenhouse gases are not the sole agents of change in this region. There’s a localized phenomenon at play.”
    There’s localized phenomena at play everywhere, nobody has claimed that GHG’s are the sole agents any more then those conclusions claim soot is the sole agent, or GHGs have no effect. OTOH, elimination of CO2 emissions would go a long way to elimination of soot emissions. The fact remains, ice is melting all over, faster than ever.

    “But some scientists claim that glaciers in the Himalayas are not retreating as fast as was believed. Others who have observed nearby mountain ranges even found that glaciers there were advancing.”
    Aside from the fact that you cherry picked something from the pop press, the single [I guess that’d be “some”] study doesn’t say what you’re implying:

    “Dozens of smaller, high altitude tributary glaciers have advanced including seven of Biafo Glacier and four of Panmah,” he says.

    “It means climate change is happening here too, but with different consequences.”
    Scientists have also described a phenomenon called glacial “surge”. This is thought to be caused by melt water underneath the glacier lubricating its ground contact and causing it to move forward. This is different from a real advance of a glacier, which is caused by an increase in the volume of ice.

    “Rapid, surge-type advances have occurred in at least 17 glaciers since 1985, at least eight since 2000 [in the Karakoram],” says Dr Hewitt.

    Meaning some, maybe all, of the apparent glacial “advance” you’re pointing to may be simply movement, not increase. It also suggests that the glaciating weather is only happening at higher altitudes

    Climate change science does seem to require intense thought for good comprehension. Hope that helps!

  49. 399
    Ray Ladbury says:

    Tom S.@363, OK, that is much better. Genuine questions, rather than irresponsible assertions unsupported by any investigation.

    1. First, there is no real evidence that the MWP was a global phenomenon. The best refutation I’ve seen of a global MWP was the Idso’s laughable attempt to show that it was global–the dates vary over a period of 600 years!!! WRT the LIA The models respond to changes in forcings–changes in insolation, volcanism.

    2. It is not the “settings” that are the problem, but rather the fact that the histories of each run diverge as the run progresses. There is an unavoidable stochastic aspect to the “noise” in the runs. A pair of models with identical forcings would tend to parallel each other. It also wouldn’t be very interesting.

    3. Why do the models not diverge much in the past if they are diverging more in the future? If it physics based, this doesn’t seem to make sense.

    Again, we know the past forcings, so there is less divergence. This is a much better way to gauge model-to-model variation.

    3a. Are there not compensating factors on the Earth that kick in and balance changes such as CO2 changes? Cloud cover, snow area, whatever? What is the expected reversing mechanism for the current temp increase?

    Temperature rise IS the main compensating mechansim for the greenhouse effect. CO2 takes a big bite out of the outgoing IR radiation, so the temperature has to rise and shift and increase the outgoing IR curve to compensate. There are of course other negative feedbacks, but no evidence of any large compensating mechansim that offsets the warming effect of CO2 without substantial rise in temperature (~3 degrees per doubling)

    4. What is the leading parameter / prediction of the climate models I can check to see how well they are performing without waiting for 30 years? Is it just temperature, or is there some other major parameter, gulf stream, etc. that is a leading indicator?

    The main “smoking gun” that we are looking at a greenhouse mechanism is the fact that the stratosphere has cooled even as the troposphere has warmed. I don’t know of another mechanism that does this. There are plenty more, but again, this is climat–you are effectively asking can I verify a long-term effect based on short-term data. Answer: Nope!

  50. 400
    Jerry Steffens says:

    Jimbo 370 and 6

    Your argument seems to be built on a couple of false dichotomies:

    (1) Either greenhouse gases are the only cause of glacial melt or they are negligible.
    (2) Either all glaciers are losing mass or none of them are.

    Try re-reading the material at the links you supplied without these biases.