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Unforced Variations: March 2012

Filed under: — group @ 1 March 2012

This month’s open thread – for appetizers we have: William Nordhaus’s extremely impressive debunking in the NY Review of Books of the WSJ 16 letter and public polling on the issue of climate change. Over to you…

617 Responses to “Unforced Variations: March 2012”

  1. 301
    dhogaza says:


    I am only an interested bystander with very limited knowledge … Even the sign of cloud feedbacks is not yet determined and the temperature measurements of recent years suggest to me little confidence that sensitivity itself can be closely bounded.

    Given your admission of limited knowledge, why should anyone care if you think that sensitivity can be closely bounded? Which, BTW, is an imprecise term, some would argue that the 2.5-4C range typically cited isn’t particularly “closely bounded”, which, despite your insinuations, isn’t supportive of complacency or inaction.

  2. 302
    dbostrom says:

    Gator: The 20th century is pretty well modeled.

    Plus it happened. Clouds don’t seem to have imposed much of a cooling effect, so far.

  3. 303
    simon abingdon says:

    #293 Ray Ladbury. “about 2.8 degrees per doubling. I don’t expect this to change during the remaining 988 years of the current millennium”. I like your confidence Ray. But does John P. Reisman (OSS Foundation) agree with you?

  4. 304
    Craig Nazor says:

    Wind definitely has something to do with the apparent ice coverage on Lake Erie on the south shore, where I lived. I remember one winter (it must have been between 1967-69), we had an extended cold spell with a strong north wind. Ice blew in from Canada, and where the ice packs met out about a half mile, the northern pack was forced above the costal pack. A high school friend of mine and I walked out to this huge pile of jumbled ice, and there was a giant, thick piece of ice that was a beautiful color of blue that thrust 20 feet above the ice plain. I understand that this blue color is the result of how the ice was formed. I will always remember it because it was so cold, windy, remote, and beautiful.

    Oh yes, and very dangerous. A snowstorm blew up, and visibility was reduced to about 5 feet. We almost didn’t get back. But what a memory!

  5. 305
    Craig Nazor says:


    Thanks for the links about Lake Erie ice cover – the chart is very interesting, as is the paper. One thing not included in the paper is ice buildup along the breakwaters along the shore, something that was very noticeable to a kid who made a game out of trying to walk on them without sliding into the frigid water. In November, the storms would blow spray onto these breakwaters, and ice would form, sometimes producing very bizarre sculptures, as well as treacherous footing. This ice would form before any ice on the lake, and would usually last until the spring thaw. The reports I have gotten for this winter (and my friend was very clear about this) is that no ice to speak of formed along the shore or on the breakwaters all winter.

    It sure would have been nice if I had written down a few systematic observations all those years ago! I was always walking along the lake, so I actually MADE the observations, I just didn’t write them down.

    [Response:Yes, and there was very little open water ice as well, essentially all in the western basin, and it was very ephemeral and unanchored. It was just too warm. You might be interested in this site–Jim]

  6. 306
    Hank Roberts says:

    > (it must have been between 1967-69), we had an extended cold spell

    lordy lord lord lord, I was in college 30 miles south of Lake Erie and I remember that winter, a Southern boy completely unprepared for such cold.

    You can’t trust Lake Erie; ever hear about this?

    Sounds like the Even Younger Dryas …

  7. 307
    Ray Ladbury says:

    The favored value for sensitivity has not changed as the error range has narrowed significantly. That is exactly what is expected in a mature field. At a certain point you simply have to accept that we “know” something. We have known the rough magnitude of sensitivity for 116 years.

    Are you similarly skeptical of the existence of atoms–where the evidence is even younger?

  8. 308
    Susan Anderson says:

    WRT Great Lakes, chasing a niggle found this at Earth Observatory, among other materials (EO had nothing more relevant on Lakes):

    Aqua satellite took this image on October 9, 2011, a little more than a week after a persistent mid-latitude cyclone moved out of the region. The storm brought strong winds to the Great Lakes region, and the resulting sediment first became visible on October 1 as the storm clouds started to move away.

    Some of the pale blue in Lake Erie may be sediment, but the green is an extremely large algal bloom. The algae may have initially spread across the western side of the lake because of windy weather, but calm weather and warm temperatures after the storm allowed green scum to build on the surface … The bloom now covers much of the western half of the lake. “This is considered the worst bloom in decades,” says Stumpf. The green in Saginaw Bay is probably an algal bloom as well.

    Though satellite imagery cannot tell us what type of algae is growing, direct measurements of the water show that the bloom in Lake Erie is mostly microcystis aeruginosa, a toxic algae. Stumpf, whose research group monitors blooms in Lake Erie, measured extremely high concentrations (1,000 micrograms per liter) of microcystin in Lake Erie during the summer. Microcystis aeruginosa produces microcystin, a liver toxin that harms mammals.

    It’s another wing to the whirligig.
    There was a lot about contamination; in many cases that is not related to climate science, just one of the many hazards of overexploitation in an interconnected world.

    Nice figure on page 5 here:
    2002, so just within the millenial bar set by the silly season above.

    I was at the U of R in ’67 (first college try) and well remember multicolored sunrise over those giant ice monster clifflike things – deformed under pressure as described above – “5,000 light years from home” …

  9. 309
    Hank Roberts says:

    “… a series of six critical thinking animations …. forms part of an education resource which covers basic logic, faulty arguments and the developing critical thinking skills. It’s designed for year 8-10 …. The accompanying education resource is found here:

    hat tip to Metafilter

  10. 310
    dbostrom says:

    Christopher Monckton spawns another organization: The Lord Monckton Foundation.

    The LMF’s objectives are characteristically modest:

    “The Lord Monckton Foundation stands as the wall of the West, the redoubt of reason, the sentinel of science, the fortress of freedom, and the defender of democracy. By this Charter, the Governing Council is directed to obtain and to deploy whatever resources may be necessary for the energetic furtherance of the ambitions and activities of the Foundation, which shall conduct research, publish papers, educate students and the public and take every measure that may be necessary to restore the primacy and use of reason in science and public policy worldwide, especially insofar as they may bear upon the rights of the people fairly and fully to be informed, openly and freely to debate, and secretly by ballot to decide who shall govern them, what laws they shall live by and what imposts they shall endure.”

    Overexposure to alliteration turns off our internal anti-bullshit firewalls; if you are susceptible to hypnosis, be careful when reading The Monckton Mission. Also, be sure not to stare too long at Monckton’s psychedelic mandala of crowns, irresponsibly placed on his website where the unwitting might accidentally become fascinated by its charms.

    Bear in mind that, unfortunate conjunctions with Monckton are innocent errors and should be overlooked.

    Monckton is presently at-large in North America. Be advised.

  11. 311

    #310–Evidently, TMF is also an important Advocate of Alliteration. With Monckton, conjunctions aren’t the only unfortunate parts of speech…

  12. 312
    David Miller says:

    A science question on an open thread.

    A friend was recently wondering why Hansen et al talked so much about silicate rock weathering as a geologic time way of removing CO2 from the atmosphere.

    According to this gentleman, carbonic acid would weather the rocks, and carbon bicarbonate and assorted ions (Ca2+ among them) would wash to the sea. That’s OK so far as it goes…

    His take, which he believes is informed by Lovelock, is that once in the ocean it must be biologically assimilated before it can be removed. If the ocean is too hot for life to fix calcium carbonate, or lacking in nutrients, saturation of bicarbonate will result and the process will equilibrates back toward gaseous CO2.

    I looked around some and didn’t find any published account requiring biotic fixing. One has to wonder, though, why all the calcium ions and bicarbonate ions don’t form calcium carbonate and precipitate out.

    So, one inquiring mind would like to know whether the biotic fixing is required or not. It seems like the ocean of the future – more acidic, warmer, fewer nutrients available due to stratification – would be much less able to support carbonate fixing life.

  13. 313
    dbostrom says:

    Interesting to note that for purposes of domain name registration the Lord Monckton Foundation shares its address with “The Climate Sceptics Party” of Australia, w/the same fellow in charge of the Monckton Foundation domain name as well as financial reports for the CSP.

  14. 314
  15. 315
    bibasir says:

    Monckton’s mission “to restore the primacy and use of reason in science and public policy worldwide” rather explicitly states that reason is not used in science. If Monckton would use science and help restore the use of science in public policy, that would be a big help, but I’m not holding my breath.

  16. 316
    bibasir says:

    I saw this release from Judith Curry. I have not read the report, so I don’t know if she attributed the decline in Arctic Ice to AGW.

    “Our study demonstrates that the decrease in Arctic sea ice area is linked to changes in the winter Northern Hemisphere atmospheric circulation,” said Judith Curry, chair of the School of Earth and Atmospheric Sciences at Georgia Tech. “The circulation changes result in more frequent episodes of atmospheric blocking patterns, which lead to increased cold surges and snow over large parts of the northern continents.”
    The study was published on Feb. 27, 2012 in the online early edition of the journal Proceedings of the National Academy of Sciences. The research was supported by NASA and the National Science Foundation.

  17. 317
    Ric Merritt says:

    SecularAnimist #283. Nice rhetoric. Some good points, but drastically insufficient. Doesn’t address any of my core points.

    Thomas Lee Elifritz #285. You don’t address my points either. I don’t get your reference to Don Lancaster, though we have a Toyota dealership in town under that name. Wikipedia and Google don’t immediately turn up anything relevant. You seem to be addressing someone advocating more FF-powered civilization, a position you couldn’t have found even a hint of in my modest comments. I’m not sure what the reference to space was about. Meaning colonies off Earth??? An impossibility I don’t spend any time thinking about. If you disagree, the onus is on you to prove me wrong by building them.

    Nobody shows any sign of having read the Do the Math blog (best to read all the posts in order). Your ignorance is showing. Go over there and contribute politely to the dialog opened up by the gracious host. Or if you are over your head, just read.

    Nuff said, I’ve made my point. Anybody who really wants a last word, have at it.

  18. 318
    dbostrom says:

    Not surprisingly, ClimateProgress puts Sherwood Rowland into modern day context, does a nice job of it.

    From the CP article:

    Nearly 40 years ago, Rowland and post-doctoral student Mario Molina made a shocking discovery: a single chlorine atom byproduct from aerosol hair sprays, deodorants and other popular consumer products could chew up 100,000 ozone atoms in the stratosphere. The stratospheric ozone layer, 12 to 30 miles above Earth, protects life on the planet from harsh solar radiation.

    “Mario and I realized this was not just a scientific question, but a potentially grave environmental problem involving substantial depletion of the stratospheric ozone layer,” Rowland said later. “Entire biological systems, including humans, would be at danger from ultra-violet rays.”
    They decided they had to advocate for a ban on consumer products that were earning billions annually. Industry representatives fought back: At one point Aerosol Age, a trade journal, speculated that Rowland was a member of the Soviet Union’s KGB, out to destroy capitalism. Even some fellow scientists grumbled that he was going overboard with a hypothesis.

    Nobel Committee: “It was to turn out that they had even underestimated the risk.”


    By 2008, Rowland was warning that given humanity’s apparent inaction on climate, “his best guess for the peak concentration of carbon dioxide” was a staggering “1,000 parts per million.”

    What’s going to stop that? Punctilious observation of an imaginary firewall between science and public policy?

  19. 319
    dbostrom says:

    Anybody who really wants a last word, have at it.

    It’s a very difficult erg substitution problem, not to be lightly dismissed?

    Leaving aside “peak oil,” Hubbert’s remarks about hydrocarbon molecules being our slaves are helpful. Hubbert of course has been excoriated in various quarters for not believing in magic but if you’re with him and rooted solidly in the material world, better get to work constructing new slaves.

  20. 320

    Rik, Do The Math ultimately means calculating the number of accessible states in a system, and then constructing a model of its structure and your desired evolution of it, and then comparing, usually through approximation, the amount of entropy created as you apply various transformations to it. Then minimize or maximize or optimize away.

    I’m sorry if that conflicts with your worldview. This is how large complex systems function from a mathematical point of view, systems far more complex than ordinary global climate models. You can simplify where appropriate or necessary, or make it as complex as you want. I suggest you start here, but there is a lot of literature out there on this subject :

    Kay, J. “The relationship between information theory and thermodynamics: the mathematical basis” (90K PDF file)

    That is, if you can still find this document. Remember, on this planet we are dealing with some very well understood prexisting biological and environmental conditions, and our knowledge of hard science is evolving.

  21. 321
    Ron R. says:

    Hello. Just wondering what people’s favorite online weather services are. Do any stand out from the rest?

    I have saved links to Jeff Masters wunderground, accuweather and intellicast. There are also various downloadable programs on the net. I stopped looking at years ago because it’s annoying bouncing, jouncing java ads, popups, popunders and loads of other advertising combined with it’s piles of cookies kept slowing down and otherwise crashing my computer. I try to avoid sites where marketing is the obvious goal.

    In any case, I’m struck by the divergent forecasts I’ve often gotten from them in the past. Probably part of the reason is the use of different stations. Sometimes though the forecasts are so conflicting you wonder if they are looking at the same sky.

    Anyway is there an, “official” or otherwise, reliable and readable weather forecasting service or program by real experts?

    Thank you.

  22. 322
    Anna says:

    Are there problems with the “Understanding the forecast” Climate Science 101 registration page? When I “Create my new account”, it returns me to the form I’ve filled in, with no error messages; and it doesn’t send me an email. Using a different browser yielded the same result.

  23. 323
    Ric Merritt says:

    dbostrom, a very informative Lindzen link in #354, new to me too. Lindzen weaves RealClimate into his web of nefarious plotting and exaggerated influence. In his telling, this website was founded by Environmental Media Services, and its contributors were recruited (careful use of passive voice here) by shadowy PR and lobbyist characters. The passive voice neatly sidesteps any direct statement that might be contradicted, but the implication is quite clear. On the friendly side, he does credit the contributors with being actual real scientists, so one wonders (well, not really) why he has to use scare quotes for “authoritative” and “truth”.

    And apropos of dbostrom #361, illuminating the deep fear of loss of individual freedom that drives Lindzen, Fred Singer, and so many others: note that in practice this means the freedom to add another billion people every 15 years, to dig up anything we possibly can and turn it into stuff we like to consume, and to protect multinational corporations from interference in their pursuit of life, liberty, and happiness. Even if the climate, unexpectedly to most of us here, turns out about the way Lindzen expects and not as that nasty IPCC would have you believe, other global limits will close in. There are many, and they are interdependent. Those now young will see more and more of their effects over a lifetime. The preference for individualism and libertarianism, healthy in many contexts, leads to failure when it ignores reality.

  24. 324
    Hank Roberts says:

    Well, here’s a nasty tradeoff. Suppose at a wild extreme that the world gave up red meat

    Remove all the climate forcings — land use, methane emission, transportation and refrigeration costs, etc.) — associated with red meat agriculture.

    Would the reduction in greenhouse gas forcing balance the increase in longevity and added cost of supporting a larger older population?

  25. 325
    Susan Anderson says:

    New topic, don’t know if this would be of interest to any of you. Ain’t our satellites wonderful (long may they live!).

    It’s from Earth Observatory’s Tohoku Earthquake page, you have to choose the most colorful image, 7 across in thumbnails below the picture here:

    The 2011 earthquake and tsunami in Japan had so many potent effects, but one of the most unusual is the one it had on the upper atmosphere. The ripples moving through the landscape and the seascape created ripples in the ionosphere, a layer above 85 kilometers (50 miles) in altitude where molecules are broken into electrons and ions by the Sun’s radiation.

    This image—a still-frame from an animation (linked here)—shows how waves of energy from the earthquake and tsunami propagated up to the edge of space and disturbed the density of the electrons in the ionosphere. The image is based on sophisticated modeling of the distortion of radio signals between Global Positioning System (GPS) satellites and ground receivers. The map shows changes in the Total Electron Content (TEC) in the ionosphere.

    The earthquake created acoustic and Rayleigh waves that moved up into the ionosphere within 10 minutes after the quake. Similarly, the motion of the tsunami also disturbed the atmosphere, creating gravity waves that took 30 to 40 minutes to reach the ionosphere. The gravity waves matched the horizontal speed of the tsunami, roughly 200 to 300 meters per second. Provoked by both the quake and the tsunami, these atmospheric gravity waves traveled over and to the west of Japan, while the tsunami was stopped by the coast.

    Ric Merritt@~323, that’s fascinating and worth remembering. Goes with Lindzen article.

  26. 326
    dbostrom says:

    Hank question: Would the reduction in greenhouse gas forcing balance the increase in longevity and added cost of supporting a larger older population?

    Doubtosphere, never alarmed: “Alarmists say we must all become vegans, submit to death panel judgement. Vote GOP.”

  27. 327
    Hank Roberts says:

    Snarkosphere: the higher on the hog your cohort eats, the sooner they and their values pass away.

    That’s true, you know. The lords get the turnips, the serfs get the turnip greens — plus a scrap of fatback which reduces mixing of oxygen during boiling, protecting the vitamins. Or so I learned decades ago.

    Maybe a discount coupon program could be arranged for those who see high on the hog as their proper position in life.

  28. 328
    dbostrom says:

    To borrow a phrase, another nail in the coffin of flattened warming.

    ” Global climate change results from a small yet persistent imbalance between the amount of sunlight absorbed by Earth and the thermal radiation emitted back to space1. An apparent inconsistency has been diagnosed between interannual variations in the net radiation imbalance inferred from satellite measurements and upper-ocean heating rate from in situ measurements, and this inconsistency has been interpreted as ‘missing energy’ in the system2. Here we present a revised analysis of net radiation at the top of the atmosphere from satellite data, and we estimate ocean heat content, based on three independent sources. We find that the difference between the heat balance at the top of the atmosphere and upper-ocean heat content change is not statistically significant when accounting for observational uncertainties in ocean measurements3, given transitions in instrumentation and sampling. Furthermore, variability in Earth’s energy imbalance relating to El Niño-Southern Oscillation is found to be consistent within observational uncertainties among the satellite measurements, a reanalysis model simulation and one of the ocean heat content records. We combine satellite data with ocean measurements to depths of 1,800 m, and show that between January 2001 and December 2010, Earth has been steadily accumulating energy at a rate of 0.50±0.43 Wm−2 (uncertainties at the 90% confidence level). We conclude that energy storage is continuing to increase in the sub-surface ocean.”

  29. 329
    Dan H. says:

    In other words, since we cannot find the missing heat, it must be in the deep oceans.

  30. 330
    Ray Ladbury says:

    Gee, that’s a really creative way to interpret that paper, since they are saying that in fact they did find the heat. More Dan H. doublespeak?

  31. 331
    Hank Roberts says:

    > More Dan H. doublespeak?

    Nope. Google his phrase; it’s a talking point also found at Watts’s, Spencer’s, Freerepublic, joannenova, tallbloke, and omniclimate.

    And that’s just the first page of the search results.

    Dan’s acting as a tube, transporting stuff from elsewhere to here.
    Anyone believe Recaptcha is an AI oracle? Its choice:
    “certainly offitYo”

  32. 332
    dbostrom says:

    In other words, since we cannot find the missing heat, it must be in the deep oceans.

    Quite likely some of it in the deep ocean but more to the immediate point also now a component is a bit more likely to be found in the upper ocean, as you’ll notice if you actually read the abstract.

    Sadly we’re not going to find all the “missing heat” in one dramatic swoop. It takes a whole bag of little nails fully pounded in to firmly close a coffin; hammering on one 40d nail only to see it bending and zinging off into eternity and then immediately moving on to another nail at another part of the lid won’t see the job done properly.

    See Trenberth’s informal comments on this paper for insight into how many nails are needed and the skill with which the hammer must be wielded. Fun stuff for spectators!

  33. 333
    flxible says:

    Most excellent interview with Mike Mann on the CBC today – reluctant public advocate for science or not you present the situation well Michael, thank you. [And thanks to the always skilled interviewer.]

  34. 334
    Hank Roberts says:

    “… the current decade has experienced the largest warming over the past 60 years.”
    PDF: Gridding daily temperature in Iceland

    P Crochet, T Jóhannesson – 2011

  35. 335
    Hank Roberts says:

    David Brin writes:

    “Michael Sterzik, an astronomer at the European Southern Observatory in Santiago, Chile, looked for biosignatures in Earthshine — the sunlight that’s been reflected off of Earth to the dark portion of the Moon’s face and then back to our planet. “The state of polarization contains a lot of information that hasn’t been used very often,” Sterzik says. Once the planetary component is thus separated, it can be analyzed for spectral components like water, methane, or even chlorophyll.

    Hm… actually, this sounds like reason to call up my old UCSD physics Masters Thesis. While my doctorate provided the modern explanation for comets (covered in a dusty, insulating layer), the earlier work was an advance in the theoretical treatment of polarized light passing through inhomogeneous, unevenly absorbing media… in other words, planetary atmospheres. …”

  36. 336
    Trent1492 says:

    I just saw a denier post this link. The link is the usual denialist chaff invoking PDO and citing the Oregon Petition and what ever to explain Alaska’s temperature rise and to claim the raise is not out of the ordinary. The interesting thing is that it is on a NOAA web site belonging to the Alaska office of NOAA.
    Anyone know what gives?

  37. 337
    Hank Roberts says:


    “one of the ways we can attempt to make some sense of data, is accomplished by approximating those graphs with a mathematical function…. such as … Fourier analysis …. I preformed this type of analysis on November through March temperature data for 11 sites across Alaska. The results clearly show that there is roughly a 20 to 30 year cycle in the temperature data, which corresponds to the PDO cycle.”

    “preformed” (sic) opinion piece, apparently.

    “Recommended WebSites:

    + Western Region Climate Center (good place for temp and precip data)

    + Global Warming


  38. 338
    Hank Roberts says:

    “any number or curve can be split into a multitude of different components, most of which will not have any physical meaning.”

  39. 339
    Hank Roberts says:


    “Wavelet analysis shows that this relative urban warming trend was primarily manifested in the form of multi- decadal and interseasonal cycles that are likely attributable to gradual increased winter heating in Ottawa (heat island effects) associated with population growth. We estimate that the 1°C increase in the Ottawa temperature is equivalent to an increase in population size of ~400,000. In contrast, interannual variability correlates well between rural and urban areas with about the same temperature amplitudes.”

    Application of Wavelet and Regression Analysis in Assessing Temporal and Geographic Climate Variability: Eastern Ontario, Canada as a Case Study
    Andreas Prokoph1* and R. Timothy Patterson2

  40. 340
    Waldo says:

    Hello, I’ve been talking with some chaps over at Climate Skeptic. One of them has challenged the current understanding of water vapor amplification. He uses some insulting language, and I apologize for that, but below is his comment and the link this poster provides:

    “The alarmist cause is dependent upon amplification by water vapor.

    “Since water vapor has gone down since 1950 the theory must be wrong mustn’t it ?

    Is this a correct understanding of the amplification? Does Real Climate have some threads or links to papers or paper titles which answer this question?

    Thank you.

    [Response: Water vapour hasn’t gone down. The chart you have been pointed at is a model result from the original NCEP reanalysis. Changes in what data are assimilated into that system over time, and changes in the quality of the radiosondes has created a false and non-climatic trend. In newer and more sophisticated reanalyses, this effect is not seen (rather the opposite is seen), and that is coherent with direct measurements – at the surface, via satellite and in the upper troposphere. People who show you this without mentioning any of the rest are guilty of serious misrepresentation. Take the rest of what they say with a great pinch of salt. – gavin]

  41. 341
    dbostrom says:

    “Since water vapor has gone down since 1950 the theory must be wrong mustn’t it ?

    A favorite. Try What does the full body of evidence tell us about humidity and/or Climate cherry pickers: Falling humidity

  42. 342

    #340–Well, probably someone more knowledgeable will have something to say about this, but in the meantime–

    First, water vapor is just one feedback, but it is definitely a major one.

    So–note that the bottom curve seems to have rising relative humidity, while the upper one has falling? And the middle one seems to fall early, then stabilize? Those curves, as the legend makes plain, show the evolution of relative humidity over time at different altitudes in the atmosphere. The bottom is near surface–the air you and I breathe–the top is around 9 km, and the middle curve is somewhere, well, in the middle.

    Guess where the mass of the atmosphere is concentrated?

    Right–near the ground, in the near-surface layer. So the rising trend in the lower curve is going to represent much more water vapor added to the atmosphere than the declining top curve represents as leaving it.

    Now, a proper analysis of this would involve actually doing the sums, not ‘eyeballing it’ as I’ve done here. You’ll find that the pros have done that–unlike your unmannerly interlocutor. Perhaps someone has a specific reference? I’d look, but I’ve got to go see if the noodles are done yet.

    (Yes, really.)

  43. 343
    Dan H. says:

    You may be interested in other work by John Papineau.

  44. 344
    Waldo says:

    Thank you. Any additional insights would be greatly appreciated.

  45. 345
    Martin Vermeer says:

    Waldo, another way to look at this is to think what would happen if this actually were true, and absolute humidity would be approximately constant when the climate warms up. It would mean that relative humidity would go down by some 7% for every degree of warming. And it is relative humidity that controls the formation of clouds and precipitation.

    Clouds form when locally, relative humidity exceeds 100%. Lower relative humidity means less clouds; how much less, I couldn’t tell; clouds are tricky and also the big unknown in current models. But less clouds means a lower albedo, bringing in though the back door a positive feedback again… and about precipitation, we as a society are much more dependent upon that than upon constant temperature. Summa summarum, the (fortunately counterfactual) absence of the water vapour feedback would concern me more, not less.

    Note also that going back to the ice ages, the glacial-interglacial temperature swing cannot be explained without full water vapour feedback on top of both the ice sheet albedo and CO2 effects. Fortunately, because with constant absolute water vapour, relative humidity would be some 5×7%=35% higher than today, and the last glacial maximum would be (counter to what we think we know) a foggy, soggy place…

  46. 346
    Paul S says:

    Trent1492 –

    I can’t see anything particularly wrong with the text in the link. I think it’s worth understanding that the author is assessing climate variability from an entirely regional perspective, a scale at which the global warming signal is much harder to detect. That’s especially true in places like Alaska where interannual variability is large. At this scale circulation changes likely do have a considerable impact, perhaps even on a multidecadal timescale.

    The inclusion of the OISM link is curious but the timing – about 2002 by the looks of it – may provide some understanding. OISM sent their stuff out to many scientists working in meteorology around this time and Papineau may have mistaken it for a legitimate reference, not having much of a background in global climate change himself.

  47. 347

    Papineau links–

    I agree with Paul. The views seem mildly skeptical, but not outrageous for someone focusing on monthly anomalies on a regional scale, and who is clearly very interested in various ‘cycles.’ They may be convenient for denialist propaganda, but they are also real, relevant, and worthy of honest study.

    But I do wonder why one would focus on regional work more than a decade old now? What would a more contemporary analysis of Alaskan data show?

    Let me look–

    OK, a simple powerpoint presentation from a Corps of Engineers official:

    Then there’s the Arctic report card, 2011, though of course that’s not limited to just Alaska:

    Or, in the scholarly literature per se, there’s this analysis:

    And, in the realm of methods, a caution that trend analysis in Alaska may not be robust wrt methodological choices:

    Biological impacts:

    Pan-Arctic information; if you can get past the paywall, I think you’d find Alaska in context:

    Somewhat similar:

    Elapsed time: maybe a half hour.

    So why are we concentrating on work that may be worthy, but is somewhat obscure and quite definitely dated?

  48. 348
    flxible says:

    So why are we concentrating on work that may be worthy, but is somewhat obscure and quite definitely dated?

    Because some contrarian stumbled upon it and its obscurity and regional nature makes it fodder for “the cause”. It appears to be data analysis specifically for improving/ understanding regional forecasting.

    Note the link is from a National Weather Service page at a regional weather center with unofficial Alaskan climate info and analyses, including other docs by the same person, and that the site generally is for weather forecasting and analysis, not climatology.

  49. 349
    Anna Haynes says:

    Question: Is the Meinshausen et al graph (down in here (link)) still considered an accurate reflection of what’s known and projected?

  50. 350
    Dan H. says:

    In short, no. The rapid acceleration in CO2 emissions depicted is seen as worst case, and highly unlikely. Although technically, this could have happened if we did not start the small switch to alternative sources.

    The projected warming is also based on high-end climate sensitivity. Again, while technically possible, this is becoming less likely. The combination of two high-end predictions, skews the graph to the high end.

    [Response: While you might wish this was true, it is not. The Nature paper this is based on is clearer. While the CO2 growth rate in the figure is based on A1F1 – a high end emission scenario yes, but not one that can be easily ruled out as impossible – the response uses a wide range of climate sensitivities that span the possible range. The probabilities of exceeding 2 deg C as a function of different emission paths is spelled out in the paper (i.e .fig 3) and show that regardless of the scenario, it is highly unlikely we will stay below 2 deg C (above PI temperatures) without climate mitigation. See also our commentary on the paper. – gavin]