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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 86201 to 86250:

  1. Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    Tom, I think more broadly, we're all being too precious. That will be obvious to the grandchildren when they look back at this stuff, if they do. If they do their question will be: "Why couldn't they have pulled _together_?" > a number of blog posts [were] published completely > dismissive of what are now seen to have been genuine > concerns. Yeah, that happens. Don't feed the trolls. Barry didn't abase himself; he did say he was wrong. Monbiot didn't abase himself; he did say he was wrong. Sure, we've got the "CO2 is Life" and "Radiation is Life" gang actively working the blogs. That stuff happens. Think about the vector sum; if we can't pull together, we can at do better than being diametrically opposed to one another. The best answer to critics nowadays, from experience: "You may very well be right about that ...."
  2. Lindzen Illusion #5: Internal Variability
    Johnny @25&26, "but of course I would appreciate if you can give me good estimate of the "natural noise"" Well, you could start off by reading the post written by Dana above. You could also read this, and this, or this, or this. The science and observations are very clear-- natural variability alone cannot account for the observed warming, not even close.
  3. Muller Misinformation #1: confusing Mike's trick with hide the decline
    Thanks for all these explanations. I understood a lot of this from other reading, but I thought that Dr. Mann had taken off the incorrect line. I also like the Climate Crock film and will watch your new shows. I understand enough to realize that it's not the climate scientists who were trying to trick me.
  4. Lindzen Illusion #5: Internal Variability
    but of course I would appreciate if you can give me good estimate of the "natural noise", so that it would make easy to test Lindzen's assertion.
  5. Lindzen Illusion #5: Internal Variability
    Albatross : I have no idea of the natural noise of the system, so I can't answer you clearly - I'm just trying to understand what is wrong with what he's saying (at least as an open possibility, if not the truth), and I still didn't get the definite counter-argument.
  6. CO2 is plant food? If only it were so simple
    Hi Chris @72, Just saw that paper. "We can see how much these variables affect crops... for example, for a crop like wheat, a degree (Celsius) of warming on a global average translates to about a 5% loss in production." And people are still trying to argue that AGW associated with doubling of CO2, and the associated warming and shifts in precipitation are not going to be an issue. Well, here we have evidence that agriculture is already being negatively affected. We are in the coal mine, the canary is sick, and some choose to think of every reason under the sun why it is not an issue, and that there is no reason to take preventative, prudent action.
  7. Lindzen Illusion #5: Internal Variability
    Johnny, Could you please state clearly whether or not you agree with Lindzen that the observed warming can be attributed to internal variability of the climate system-- that is, his belief that the observed warming is within the natural noise of the system. Thanks.
  8. Lindzen Illusion #5: Internal Variability
    Rob#20 : again the Earth is not a closed system, you seem to imply that heating of one part implies cooling of another part - but this is wrong, the Earth is constantly absorbing and reemitting much more energy than it stores, and variations of the heat content can occur with small imbalances due to any cause of variability (for instance oceanic circulation), without "cooling" anything anywhere.
  9. Lindzen Illusion #5: Internal Variability
    "Thus, the rate of energy building up since 1970 is equivalent to 2.5 Hiroshima bombs every second." Sorry but this is nothing, since the energy imbalance is supposed to be about 1W.m-2 so 1/1000th of the incoming solar power. What do you mean with your Hiroshima bombs? it's always 0.1 % of the solar irradiance ! I was just trying to understand this statement : "But if the movement of heat from the deep oceans is what's causing the surface air to warm, this hypothesis requires that the oceans as a whole and deep ocean layers in particular must be cooling." and I still don't get the point. Actually I even don't see any possibility that heat would flow from the deep cold ocean layers to heat the warm surface, this would contradict the second principle ! so obviously internal variability does not transfer heat from deep ocean, upwelling of lower layers can only cool the surface- but still why is internal variability, for instance of the surface heat transfer processes, excluded ? or rather what is its natural limit, since we seem to all agree that it exists at some level ?
  10. Lindzen Illusion #5: Internal Variability
    Pete @17, "Dorlomin, certainly Lindzen must have done very good work in meteorology to have an endowed chair at MIT. But that was then, this is now." You have just hit the nail on the head. What I find bemusing is when 'skeptics' uncritically lap up Lindzen's BS (Bad Science), and worse yet, try and defend it.
  11. Rob Painting at 01:17 AM on 9 May 2011
    Lindzen Illusion #5: Internal Variability
    Johnny @ 16 - "I meant barring the effect of GHG, is there still room for variability ? I still don't understand why the OHC should stay constant if there is variability?" If the OHC is so variable, where do you think all that heat could go?. Natural variability in this context simply means the exchange of heat between the oceans and the atmosphere. Consider the specific heat content of water compared to the atmosphere, if a significant proportion of that ocean heat were released to the atmosphere, we'd see rapid global warming, but the oceans would have to cool. No way around that.
  12. Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    Barry Brook @19, it seems to me that you are being too precious. You want, at the same time, to consider Dr Washington's calling nuclear a "false solution" an insult, but decree that calling Dr Washington "misinformed" is not ad hominen. Saying that something is a false solution says no more than that something appears to be a solution, but is not one. Any insult you read into what amounts to a simple statement of an opinion you disagree with is entirely your own problem. I have to say that while I am open to the use of Nuclear power as probably being necessary to avoid excessive global warming, advocates of that view have not covered themselves with glory lately. In particular, at the start of the Fukushima accident, a number of blog posts where published completely dismissive of what are now seen to have been genuine concerns. Your own claim that, " There is no credible risk of a serious accident" shows in hindsight that you have rose coloured glasses when it comes to nuclear issues. I have no problem with that. Without enthusiasms or concerns, nobody would take the effort to become reasonably informed on any topic. But when you couple that with an attitude which sees any critique as necessarily insulting and uninformed, nothing is suggested as much as a closed mind.
  13. Pete Dunkelberg at 23:30 PM on 8 May 2011
    Lindzen Illusion #5: Internal Variability
    I want to add that I appreciate Dorlomin's point and it is a good one. It's just that sometimes it isn't good enough.
  14. Ken Lambert at 23:12 PM on 8 May 2011
    Lindzen Illusion #5: Internal Variability
    dana1981 original post Both Fig 1 and Fig 2 have been discussed in detail elsewhere on this blog. Fig 1 has the dubious 'step jump' in the 2001-03 period where Argo measurement took over. The linear trend line showing a global +0.64W/sq.m for 1993-2009 is likely bogus because the step jump does not show in the satellite TOA data. Fig 2 " And Purkey & Johnson (2010) reconstructed ocean heat accumulation down to abyssal depths and found significant amounts of heat building up even at the bottom of the ocean (Figure 2)." Well they found globally a sum of about 0.09W/sq.m below 1000m which is only one tenth of the claimed global warming imbalance of 0.9W/sq.m. Not that significant at all.
    Response:

    [DB] The rate of energy building up since 1970 is equivalent to 2.5 Hiroshima bombs every second.

    Nope, not significant.

  15. danielbacon at 22:43 PM on 8 May 2011
    Climate Change Denial book now available!
    I am with the others on the Kindle version, my wife will not allow hard copies to be added our library not only for environmental reason but there is no more space in our house for more books. Any idea when or if it will be available?
  16. Pete Dunkelberg at 22:20 PM on 8 May 2011
    Lindzen Illusion #5: Internal Variability
    Dorlomin, certainly Lindzen must have done very good work in meteorology to have an endowed chair at MIT. But that was then, this is now. He is not highly cited (in the literature) for his climate work of recent years. Instead he has made a practice of saying in public things he would not even try in scientific public publication. "He says crazier things in public than he does in his papers" is very close to a quote from RC if I recall correctly. IMHO he has lost his moral bearings. As a scientist he should know that if he can not make his case scientifically (and considering the consequences for all of us if he is wrong and believed) then it is highly irresponsible to keep saying what he says in public. By the way Tamino has had enough.
  17. Lindzen Illusion #5: Internal Variability
    "If atmospheric levels of GHGs are stable (irrespective of other forcings like the sun) then temps will be within the range of normal variability." I meant barring the effect of GHG, is there still room for variability ? I still don't understand why the OHC should stay constant if there is variability? you mean that it is strictly constant, or that it can only vary with a limited amplitude ? (which is what ?)
    Response:

    [DB] The measured changes in heat content of the Earth:

    HC

    [Source]

    Thus, the rate of energy building up since 1970 is equivalent to 2.5 Hiroshima bombs every second.

    For natural variability to be able to explain away what we measure, there would have to be plausible physical mechanisms to explain the increases we see.  Said mechanisms would also have to explain away why the measured increases in GHG (which we can tell are anthropogenically-sourced) do not also cause an increase in total heat content.

    No such plausible physical mechanisms have been given.

  18. Lindzen Illusion #5: Internal Variability
    To indulge is something a tad frivolous AC Clarkes first law: "When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong."
  19. Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    Just in terms of balance, there would also seem to be a need for studies on those psychologists, sociologists and scientists etc. who base their analysis of denial on the assumption that CO2 theory is proven, and hence is undeniable.
    Response:

    [DB] I don't speak for psychologists or sociologists, but scientists in general do not:

    base their analysis of denial on the assumption that CO2 theory is proven, and hence is undeniable.

    The current level of Scientific Consensus on climate change was expressed most recently by the National Academy of Science in their publication Advancing the Science of Climate Change.  In it they specify (p. 17): 

    A strong, credible body of scientific evidence shows that climate change is occurring, is caused largely by human activities, and poses significant risks for a broad range of human and natural systems….
    Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small.

    Such conclusions and theories are then regarded as settled facts.

    This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities.

    Very likely” means a greater than 90% likelihood of probability; i.e., pretty certain.

    All that being so, there is still an element that would have us debate the existence of gravity...

  20. Lindzen Illusion #5: Internal Variability
    owl905 "No he isn't. If his last name wasn't MIT he wouldn't get the time of day from a watchmaker" Au contrair. He is on the ISI highly cited list. http://hcr3.isiknowledge.com/formViewCharacteristic.cgi?table=Publication&link1=Browse&link2=Results&link3=Biography&id=2422 Making him one of the most respected atmospheric physicists on the planet. He may be wrong on sensitivity but has made many important contributions to his repective field.
  21. Barry Brook at 21:08 PM on 8 May 2011
    Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    Hayden Washington, I cannot see how my comment would be construed as an ad homenim. To do this, I would have to disparage your character, and use that as a basis for dismissing your arguments. Instead, I saw in your comments a number of things: 1) Ironic: "using multiple strategies that work. The technological solutions exist, such as renewable energy and energy efficiency" Multiple strategies that apparently do not include nuclear energy, which we know WORKS and has been the only low-carbon energy technology, excepting large hydropower dams, that has been successful to date at displacing coal, or in running an electricity system at high penetration (France). The best non-hydro renewables have done is 19% (Denmark). 2) Insulting: "We also discuss ‘false’ solutions such as nuclear power and carbon capture and storage, which involve their own denial of problems." You are disparaging me, as well as other climate scientists such as Jim Hansen and Tom Wigley, and other prominent thinkers like David Mackay, James Lovelock, Mark Lynas, George Monbiot, Chris Goodall, and many others, who have evaluated the situation logically and cannot see a viable solution without a significant role for nuclear (along with renewables and energy efficiency). Instead, you accuse us of denial and offering 'false' solutions, as though we were trying to hide from some truth or deliberately dissemble. As I said, this is insulting. 3) Misinformed: That applies to both 1 and 2 above. Further, if you would become better informed about nuclear power, then you might not be so ready to dismiss it. If you are as concerned about the extremely serious consequences of climate change, as you profess, you should judge nuclear power's benefits alongside its faults (real and perceived) and make a prudent decision that is explicit about this very serious trade off. If you did indeed listen to the UNSW debate and took nothing from it but MD's unsubstantiated opinion (i.e. real-world experience), and ignored everything I said, then I'm frankly staggered. I support renewable energy and any other practical solutions to displacing fossil fuels. I have set up a research project (Open Science) called Oz Energy Analysis (http://oz-energy-analysis.org) to assess how Australia might reach as much as 50% renewables by 2030. However, I also subject renewable energy to the same scrutiny as I subject any scientific hypothesis, and that is why I am surprised and disappointed that the two critiques of the BZE 2020 plan has received exactly zero responses: http://bravenewclimate.com/2010/08/12/zca2020-critique/ and http://bravenewclimate.com/2010/09/09/trainer-zca-2020-critique/ We must face up to reality if we are to solve these extremely difficult problems. Your approach seems cavalier at best and grossly irresponsible at worst. "not follow some Cornucopian nuclear fantasy" Throwing such straw men at me serves no purpose other than to undermine your credibility. Since when did I claim this? Indeed, my guest post on Skeptical Science, Can animals and plants adapt to global warming?, shows my research focus - ecology, evolution and extinction, and the impacts of human activity on the biosphere. I understand the concept of ecological limits better than most, so I'd ask that you do a little more background research in future before throwing around such aspersions. In short, if the above arguments you presented are in any way indicative of the quality of writing in the book, then I'm unlikely to purchase a copy or recommend it. Which is a shame, because I have a great deal of respect for the work that John Cook does on this site.
  22. Lindzen Illusion #5: Internal Variability
    I may have missed the point, but why does the internal variability preclude an increase of the heat content of oceans, since Earth is not a closed system ?
    Response:

    [DB] Due to the radiative physics of greenhouse gases.  If atmospheric levels of GHGs are stable (irrespective of other forcings like the sun) then temps will be within the range of normal variability.

    As we can measure long-term increases in levels of CO2 and methane (CH4) we know that the system will be in radiative disequilibrium, retaining more energy than it receives.  This will occur until enough energy is retained to restore the balance at the Top Of the Atmosphere (TOA).

    Due to the thermal lag of the oceans, we are just now receiving the warming effects of the extra CO2 man injected into the carbon cycle back in the 60s and 70s.  Thus even a zero-sum emissions strategy maintained for decades will still see rising temperature levels for decades.

    To return to your question, if internal variability precludes increased OHC, then the physics of anthropogenically-sourced GHG increases must be different than those GHGs found naturally in the carbon cycle.  And multiple other indicators of a warming world must also be magically waived away as well.

    More can be found at the article linked in the original post at top,

    "How do we know more CO2 is causing warming?"

  23. alan_marshall at 20:13 PM on 8 May 2011
    Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    Michael Sweet @ 10 I welcome this timely book by John and Hayden, and look forward to reading it. In relation to the argument you put, I agree that it helps explain why some Christians are apathetic about climate change. However, I don’t believe they are unreachable. Another new book, co-authored by a climate scientist and an evangelical Christian, respectfully puts the case for climate action in the context of a Christian world-view: Kathrine Hayhoe aned Andrew Farley, A Climate For Change: global warming facts for faith-based decisions, Faith Words, New York 2011 Suppose for a moment that the Christians you refer to are right and that the creator comes back to wrap up the show 25, 50, 100 or 200 years from now (before we totally destroy ourselves). Does that mean that we should go on trashing his creation until he returns? I put it to you that displeases him. It may even be, if you see bible prophecy the way I do, that some of the calamities prophesied are consequences of our environmental vandalism. Two of my own publications that may interest you are a Bible study guide Christians and the Environment, and my paper Shaping a Sustainable World, published in the Notre Dame Journal of Law, Ethics and Public Policy, which argues the need for climate action from a Judeo-Christian perspective.
  24. martinrkellogg at 18:12 PM on 8 May 2011
    Lindzen Illusion #5: Internal Variability
    A better link for Purkey and Johnson (2010) -- "Warming of Global abyssal and deep Southern Ocean waters between the 1990s and 2000s: Contributions to global heat and sea level rise budgets*" -- should be here (if I copied it correctly), as no payment is required to see the full article. Otherwise, it can be accessed quickly at this location.
    Response:

    [DB] Fixed URLs.  Posting tips can be found here.

  25. Lindzen Illusion #5: Internal Variability
    dorlomin wrote:- "Lindzen is a genuinely great atmospheric physicist." No he isn't. If his last name wasn't MIT he wouldn't get the time of day from a watchmaker. His iris, his cooling trend since (latest date goes here), his 'missing hotspot' and tropics focus, the 'clouds' problem ... it's one 'butwaddabout' after another. His own explanations don't net out to rigorous science; they come across like 'nya nya can't make me' dodges.
  26. Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    An Interesting looking book. It should fit in well on my shelf next to 'Hubbert's Peak', 'The Boswick Report' & 'None Dare Call It Treason'.
  27. Lindzen Illusion #5: Internal Variability
    Funglestrumpet - They get away with it because organisations like Murdoch's News Corp are actively following an anit-AGW agenda. They use what Garnaut has described as a "curious kind of balance - a balance of words rather than scientific opinion". They conduct the debate in political terms rather than scientific terms. This means that for every black there must be a white, there can be no shades of grey. For every left there must be a right, you get the idea. The rest of the media follow this same method. This means that if right wingers such as Howard and Bush support the skeptics then it must follow that AGW must be a left wing theory. You just cannot have a scientific theory that is independent of politics. Even organisations like the ABC feel that they must provide equal time to "the other side". This is how the 3% skeptics leverage there media presence up to 50% or more. I started to watch a global warming doco on SBS a few nights ago. It followed a very simplistic formula of one opinion from that side, one opinion from this side. They had Christy as the token skeptic, possibly because he has a big moustache and looks like a cool scientist. They gave him 3 minutes then the other side 3 minutes then they started to talk about electric cars for no apparent reason, maybe they were sponsored by Nissan. Anyway that's where I turned it off. We know that if you were to present one opinion from each side then you could easily have 1000 opinions, 970 of which would be pro-AGW. But the mass media, especially television can't work with that, in the mind of a producer of a TV doco there can only be 2 sides, so they find two opposing views, present them as though that was all there was, then walk away smugly satisfied that they have presented a show that was balanced and unbiased. I've got no idea how to break through this kind of simplistic dumbing down of the debate. Given that Channel Ten has now given Bolt his own TV show, I don't believe that any mass media organisation, whether its TV or newspapers, will ever provide an honest comprehensive coverage of the global warming debate.
  28. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Tom, Eli got a copy of the data for the graph by writing to Frauenfeld.
  29. David Horton at 11:30 AM on 8 May 2011
    Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    Bravo Haydn, well said. The push for nuclear is both cynical and frightening. The problem, as I wrote about 2 years ago on ABC Unleashed (to a massive response, people are really concerned about this) http://www.abc.net.au/unleashed/30624.html,is that no matter what improvements in technology occur, the chance of human error is always there, and the consequences, as seen in Japan most recently, are extreme and widespread.
  30. Lindzen Illusion #5: Internal Variability
    KR - I think that was dorlomin's point. Policy (i.e. a lack of action on global warming) is being made on the basis of idiosyncratic minority views (i.e. Lindzen, Christy, Plimer, and their friends, a number of whom have no specific expertise in this area), while dismissing or ignoring the views of the 99% of climate scientists who think we have a serious problem on our hands.
  31. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Below is FK&M 2011's key figure modified to include a 2010 value and to change the 10 year trailing mean to a straight 10 year mean. The 2010 value is calculated from Tedesco's figure as detailed @183. The image was made purely by manipulating images. What difference does it make? 1) The 2010 value falls within the 95% confidence limits of eight, or possibly nine of reconstructed pre 1979 values, compared to twenty for 2007. 2) The 10 year mean ends with a value of 0.9 compared to 0.7 for 2009. For comparison, the peak of the 10 year mean in 1 in 1924. 3) A minor graphical point, the 10 year mean ends with an uptick instead of levelling of as it does without 2010 included. These may look like minor features, but viewed at normal viewing scale, they do stand out and give a distinctly different impression. In particular, when coupled with the trailing mean, ending at 2009 gives the visual impression that the most recent melt values may have reached a peak at a decadal mean distinctly lower than the peak in 1924. Including 2010 and using a standard 10 year running mean, in contrast, gives the visual impression of a still rising value which is already at the same levels of the 1924 peak. I think this difference is important for spin, but not in science. Contrary to some commentators I do not think the use of a trailing mean is 'unscientific'. It is certainly not best practise, and can mislead the unwary, but it will not mislead anyone who actually reads the captions (unless they want to be). On the other hand, I do think the difference between 0.7 and 0.9 on the 10 year mean, and between the peak recent value lying within the confidence interval of just eight rather than 20 reconstructed values is scientifically relevant. That difference approximately doubles our confidence that the most recent peak value is in fact the actual peak value over the entire period, at least using Lucia's simplistic interpretation of confidence intervals. The difference in ten year means also significantly increases our confidence that current melts have at least matched and will probably soon exceed those of the 1920s. It also gives us reasonable confidence that they already exceed those of any other decade. That last point probably deserves some attention. It is a clear emphasis of FK&M 2011 that "We find that the recent period of high‐melt extent is similar in magnitude but, thus far, shorter in duration, than a period of high melt lasting from the early 1920s through the early 1960s." (My emphasis) However, the recent period including 2010 exceeds in magnitude all but one decade of of that forty year period. Given that 2010 also appears to be confirming Box's very plausible prediction, it would be a foolhardy person to argue from FK&M that ice melts in Greenland will soon, if they do not already, cause far more rapid rises in sea level than at any time in the twentieth century.
  32. haydnwashington at 10:47 AM on 8 May 2011
    Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    I guess two points: 1) Re probability and certainty, Cloa seeks to argue that 'true science' comes with 'proof' while climate science is rubbery. This is a common denial argument which paints mainstream climate science as 'junk science'. The reality is that the coherence of evidence in regard to human-caused climate change is overwhelming. It comes from many sources and almost all show that warming is worse than it was orignally projected to be. In regard to the statement about scientific method in general, this is just mistaken, as any book on the history and philosophy of science will explain to you. 2)Barry Brooks seeks to make an ad hominem attack that since I doubt the usefulness of nuclear power I am either ironic, insulting or misinformed. Well sorry Barry I am not being ironic, nuclear is too little too late, too expensive and too dangerous. You dont solve one major problem with another. You might consider it if it was the only alternative - but it isnt. As was shown in your debate with Dr Mark Diesendorf at UNSW, renewable energy is a far better alternative to put our development money into than nuclear. Issues such as baseload power are now solved. Spain is spending $20 billion on installing Concentrated Solar Thermal. It is time for Australia to make use of our fantastic renewable resources, not follow some Cornucopian nuclear fantasy. Renewable are both feasible and sustainable. Its time to accept reality and move rapidly to a renewables future. Both Mark Diesendorf and Barry Pittock in their books (plus Beyond Zero Emissions in their Stationary Energy Study)show this can be done.
  33. Daniel Bailey at 09:26 AM on 8 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    As a furtherance to Albatross' comment at 161 above, there is a new release from Snow, Water, Ice, Permafrost in the Arctic (SWIPA) 2011 entitled: Executive Summary and Key Messages English translation here (WARNING: Big File [31 Mb]; fast connections only!) For those without high-speed access: Key finding 1 The past six years (2005–2010) have been the warmest period ever recorded in the Arctic. Higher surface air temperatures are driving changes in the cryosphere. Key finding 2 There is evidence that two components of the Arctic cryosphere – snow and sea ice - are interacting with the climate system to accelerate warming. Key finding 3 The extent and duration of snow cover and sea ice have decreased across the Arctic. Temperatures in the permafrost have risen by up to 2 °C. The southern limit of permafrost has moved northward in Russia and Canada. Key finding 4 The largest and most permanent bodies of ice in the Arctic – multiyear sea ice, mountain glaciers, ice caps and the Greenland Ice Sheet – have all been declining faster since 2000 than they did in the previous decade. Key finding 5 Model projections reported by the Intergovernmental Panel on Climate Change (IPCC) in 2007 underestimated the rates of change now observed in sea ice. Key finding 6 Maximum snow depth is expected to increase over many areas by 2050, with greatest increases over Siberia. Despite this, average snow cover duration is projected to decline by up to 20% by 2050. Key finding 7 The Arctic Ocean is projected to become nearly ice-free in summer within this century, likely within the next thirty to forty years. Key finding 8 Changes in the cryosphere cause fundamental changes to the characteristics of Arctic ecosystems and in some cases loss of entire habitats. This has consequences for people who receive benefits from Arctic ecosystems. Key finding 9 The observed and expected future changes to the Arctic cryosphere impact Arctic society on many levels. There are challenges, particularly for local communities and traditional ways of life. There are also new opportunities. Key finding 10 Transport options and access to resources are radically changed by differences in the distribution and seasonal occurrence of snow, water, ice and permafrost in the Arctic. This affects both daily living and commercial activities. Key finding 11 Arctic infrastructure faces increased risks of damage due to changes in the cryosphere, particularly the loss of permafrost and land-fast sea ice. Key finding 12 Loss of ice and snow in the Arctic enhances climate warming by increasing absorption of the sun’s energy at the surface of the planet. It could also dramatically increase emissions of carbon dioxide and methane and change large-scale ocean currents. The combined outcome of these effects is not yet known. Key finding 13 Arctic glaciers, ice caps and the Greenland Ice Sheet contributed over 40% of the global sea level rise of around 3 mm per year observed between 2003 and 2008. In the future, global sea level is projected to rise by 0.9–1.6 m by 2100 and Arctic ice loss will make a substantial contribution to this. Key finding 14 Everyone who lives, works or does business in the Arctic will need to adapt to changes in the cryosphere. Adaptation also requires leadership from governments and international bodies, and increased investment in infrastructure. Key finding 15 There remains a great deal of uncertainty about how fast the Arctic cryosphere will change in the future and what the ultimate impacts of the changes will be. Interactions (‘feedbacks’) between elements of the cryosphere and climate system are particularly uncertain. Concerted monitoring and research is needed to reduce this uncertainty. The biggest unanswered questions identified by this report are: • What will happen to the Arctic Ocean and its ecosystems as freshwater is added by melting ice and increased river flow? • How quickly could the Greenland Ice Sheet melt? • How will changes in the Arctic cryosphere affect the global climate? • How will the changes affect Arctic societies and economies?
  34. Lindzen Illusion #5: Internal Variability
    dorlomin - I'm afraid the idiosyncratic minority view is Lindzens, not the consensus. I cannot speak to policy, as the US really doesn't have one at the moment. Lindzens climate sensitivity numbers are way out on the fringe, his science and claims are poorly (if at all) supported, his views have been debunked. Sorry... I'll respect the time he's put in - but his views are nonsense when compared to the evidence.
  35. Lindzen Illusion #5: Internal Variability
    @David Horton post 5. Lindzen is a genuinely great atmospheric physicist. He has a view that dissents from the mainstream. But there is nothing unusual in that, many scientists who produce great work in a field have odd views on other areas of that field. Often scientists looking at the same evidence come to differing conclusions. Look at Out Of Africa vs Multiregional in terms of human evolution, the same bones were used by both sides to make their cases. Lindzen holds his view honestly and is entitled to it. The problem comes that policy is being based on ideosyncratic minority views rather than the bulk of the scientists.
  36. funglestrumpet at 08:45 AM on 8 May 2011
    Lindzen Illusion #5: Internal Variability
    David Horton - You may be right. However, there is something wrong if they can be allowed to get away with such behaviour. In any event, there must be something that can be done to expose the weakness of the support they get from their peers. In the eyes of the public, the case you advance comes down to two arguments, both difficult to grasp. The concept of the relative support from their peers is not part of the equation. Something I hoped to promote. There is surely a need for action when debunked material can be presented for "two decades" with no shame on the part of those concerned. What I suggest would give those who wish to 'trot' out such individuals an accessible resource to get a feel for the quality of their proposed guests. Most importantly, they would not need to know the science, the language on its own would speak volumes. It could even be seen as a resource that could be pointed to in any letters of complaint to the heads of organisations when some Presentations Director has booked the likes of Lindzen and suchlike.
  37. Steve Bloom at 08:18 AM on 8 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Any chance of getting error bars added to the graph, Chris? Re that '20s/'30s bump, someone said earlier that it was down to solar influences. IIRC that's not right, although perhaps it's a small factor, and the big one (scraping my memory here) was likely black carbon from industrial emissions.
  38. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Below are a couple more graphs; I’ve aligned them together so that they are easier to compare, with a description above all the graphs. See additional comments here for info on where the data comes from. A. as presented by FKM2011 with a 10 year trailing running average. B. as a 10 year running average should be presented (i.e. without a lag) – This shows the data up to the year up to which the running average can be calculated. Obviously the more years in the running average, the more years at the front and back of the series are left uncalculated. There isn't any justification I can think of for shifting the running average as if to pretend that the average has been calculated for each year to the end of the series; it hasn’t. Another way of saying this is that the averaged melt index value of around 0.5 was reached already by 2004. It didn't take until 2009 as FKM's analysis pretends. What it does next depends... C. as a 5 year running average, and incorporating the 2010 melt data, which differs a little from my previous post to accommodate the evidence that the 2010 melt was a little larger than 2007. I found I couldn’t reliably do this exactly as Tom suggested in @183, since the FKM data and Tedesco data aren’t related by a single specific scaling factor. So I’ve somewhat arbitrarily given 2010 a melt index of 2.2. It doesn’t make much of a difference if it is 2.0 (same as 2007), 2.1 or 2.2. The melt index value at the end of the record (2008) has a value very near 1.0. Make of it what you will. FKM's smoothing is somewhat illiterate scientifically-speaking, but they are trying to sell a particular message and the reviewers gave them a pass on this. On the other hand the real impact of the high 2010 melt year will only be apparent if subsequent years are also high or higher. If that happens to be the case as physics might predict, then a robust 10 year smoothing of the data should help to suppress the rise for a little longer! A. B. C.
  39. David Horton at 07:45 AM on 8 May 2011
    Lindzen Illusion #5: Internal Variability
    Fungelstrumpet - Lindzen serves (as does Plimer) as the kind of token "respectable" scientist who "doesn't believe" in global warming who can be trotted out, again and again to show that "the science isn't settled" (otherwise respectable scientists wouldn't dispute it) and the consensus is not 100% (only 99% therefore there is room for doubt). Lindzen seems absolutely content with this role. Not much need to scientifically dispute him in the ordinary sense (yes there is "natural variability" but every graph shows it is occurring around a rising mean; what are the odds of "natural variability" not only coinciding with low sun input but sharply rising CO2 in the past 30 odd years?). As with Monckton however, his importance is not in the rubbish science but simply that he exists and is vocal and highly visible.
  40. Lindzen Illusion #5: Internal Variability
    Didn't Hansen et al. (2011) actually conclude that the Earth's energy imbalance had decreased? "In this section we examine why the calculated energy imbalance declined during the past decade. In section 13 we discuss factors that may account for the difference between expectations in Fig. 19A and the observed planetary energy imbalance." (pg. 36)
  41. funglestrumpet at 05:08 AM on 8 May 2011
    Lindzen Illusion #5: Internal Variability
    dana1981 – doesn’t seem to be working, does it? At the moment it is all via proxies. I believe we should take the fight to them, heaven knows, the science sits fair and square on this side of the fence. As it is, anyone that has little or no science is just going to see one side saying one thing and the other side saying the opposite, both statements being impenetrable. What I am suggesting provides a mechanism that raises awareness. One does not have to understand the science to recognise waffle when one sees it. I really don’t think that business as usual is a luxury that we can afford for too much longer.
  42. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Logicman @168, Good sleuthing. The mind boggles. Regarding the JGR-A numbers, I could be wrong, but I'm pretty sure that those numbers represent the number of downloads. If so, right now, the paper in question is in third place. For what it is worth, the paper doesn't feature under "editors" highlights"-- no surprise there, they are probably embarrassed about it. That all aside, I find it odd that the "skeptics" denounce popularity contests or polls, yet as soon as a 'skeptic' paper gets quite a few downloads they get all excited. A good number of those downloads are probably by glaciologists thinking "WTF?!".....I'm sure Lindzen and Choi also ranked high shortly after it was published ;) Chris @179, nice work! Looking forward to seeing the your updates should you decide to pursue this further.
  43. Lindzen Illusion #5: Internal Variability
    funglestrumpet - Lindzen's arguments don't have any impact in and of themselves. Where they have an impact is when somebody references them to propagate and defend a climate myth. Here we are providing a counter-reference to deflate the value and effectiveness of Lindzen's arguments. If people make use of this resource, then others will notice.
  44. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    #170 - Albatross Here's a similar quote from Michaels posted on Forbes. "In an unbiased world there should be an equal chance of either underestimating or overestimating the climate change and its effects, which allows us to test whether this string of errors is simply scientists behaving normally or being naughty. What’s the chance of throwing a coin six times and getting all heads (or tails)? It’s .015. Most scientists consider the .050 level sufficient to warrant retention of a hypothesis, which in this case, is that the UN’s climate science is biased." Forbes.com The worst counterfactual statement there by Michaels is: "Scientists, as humans, make judgemental errors. But what is odd about the UN is that its gaffes are all in one direction. All are exaggeration of the effects of climate change." Elsewhere, the new maths: 54 = 1 Last week, the most popular article from among those recently published in the American Geophysical Union’s (AGU) Journal of Geophysical Research-Atmospheres was one which presents a 225-yr reconstruction of the extent of ice melt across Greenland. my emphasis. The image posted shows the paper as 54th most popular download. http://www.worldclimatereport.com/...
  45. Ian Forrester at 03:59 AM on 8 May 2011
    Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    Barry Brook said:
    are you trying to be ironic, or insulting, or are you simply misinformed?
    He is being honest, think about it for a few minutes.
  46. funglestrumpet at 03:51 AM on 8 May 2011
    Lindzen Illusion #5: Internal Variability
    Just how many times must we simply sit back and allow Lindzen to give us his illusions, Monckton with myths and Christy his crocks? Isn’t it about time this community took the initiative? How about asking Lindzen and his compatriots for their response to these debunking posts and tell them you are going to make public the challenge and also the ensuing correspondence to a conclusion? If a point is reached where a stalemate is reached, the opportunity to join in is offered to those most competent to contribute. This site has enough kudos to be able to contact anyone these ‘sceptics’ happen to use to publish their disinformation and show them how much they have been deceived. It is fun to see their arguments being demolished, but like the warm feeling one gets from peeing ones pants while wearing a dark suit, who notices?
  47. Bob Lacatena at 03:38 AM on 8 May 2011
    Why 450 ppm is not a safe target
    44, Jesús,
    I think Hansen tries to add something to the literature, and I think it's the suggestion that all current projections may be too low.
    Yes, absolutely, and I get the impression that the 2011 paper is intended to provide further weight to this argument, through paleoclimate evidence (i.e. comparison to Eemian temperatures and sea levels, without reference to time frame). I think I separate from you in that I think that Hansen, and RC's interpretation of Hansen, is that he never actually made any specific projections, and certainly not within any particular time frame. He is pushing the idea that sea level rise will be non-linear, and in the simplest model for that (ice loss doubling every 10 years) this would project to a 5m increase by 2095... but he's not putting that out there as a serious prediction, only as a stark example of the potential difference between linear and non-linear. I think that since then he has gone out of his way to avoid being specific. He is pushing the idea of a non-linear sea level rise without making any specific predictions relative to time-frame. I think RC understands this thoroughly, which is why they appear to be silent. They don't refute 5m because they don't feel any such prediction was ever made. They don't refute "meters" because it is an unbounded, non-specific warning.
    I don't think 1.5 m is "multi-meter"
    I don't either. Without coming out and saying it, I think Hansen is implying 2m-5m, with the idea that 2m is at the low end, and anyone projecting below that is in for a surprise... but he's never come out and said that... this is my interpretation.
    I think that's what most readers are interpreting...
    No, I think they're taking away 5m because that's what the post above says, and it should be rectified ASAP, because it's going to confuse people.
    what is important, in my view, is that, when talking about Hansen & Sato SLR numbers, we stress that the most widely accepted projections for 20th century SLR cluster around 1 m.
    Agreed (except I know you meant 21st, not 20th, century), as long as people understand that those numbers presume a linear increase, and there are reasonably strong arguments to at least consider that that may not be the case, and we may be underestimating the problem (for the second time). I think the last bit from Hansen and Sato 2011 worth pointing out is this:
    We conclude that available data for the ice sheet mass change are consistent with our expectation of a non-linear response, but the data record is too short and uncertain to allow quantitative assessment. The opportunity for assessment will rapidly improve in coming years if high-precision gravity measurements are continued. Finally, we note the existence of a strong negative feedback described by Hansen (2009) that comes into play when the rate of sea level rise approaches the order of a meter per decade. Such an iceberg discharge rate temporarily overwhelms greenhouse warming, cooling high latitude atmosphere and ocean mixed layer below current levels. Ice sheet mass loss may slow in response to this cooling...
    That last bit, if it ever comes to past (certainly not in our lifetimes, I'm sure) is a downright scary image.
  48. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    A general point/opinion about this story of which I think there are 3 elements (I hope the moderators consider my comments appropriate since this thread clearly isn’t just about the science; it’s also about science misrepresentation, Greenland melt and the scientific review process): 1. Misrepresentation of science. It’s very sad that enormous sums are invested in institutions whose purpose is to cheat Joe Public out of one of the essential requirements of a democracy (the information required to make informed decisions). The posts by Albatross from #161 onwards, are probably the most relevant on this thread, since they address a particularly ugly problem. 2. Greenland ice melt. It’s a simple fact that when viewed in terms of raw numbers without consideration in the context of independent knowledge, Greenland ice melt doesn’t seem to be so very much different now that during the early-mid 20th century......yet. This can easily be misrepresented. 3. Scientific review. However the data was presented in FKM2011, they would have been used to support dismal rhetoric of the sort that Albatross has highlighted. However, IMHO some of the problems could have been addressed if at least one reviewer had chosen to review the paper properly. I detect an undercurrent of potential unhappiness about the editorial decisions on this paper, but in the absence of inside knowledge (which I have little interest in - although if it does appear it's bound to be gossipworthy!) I am going to support the editor here. He gave the manuscript to an expert reviewer, and the latter decided not to bother reviewing the paper properly. We know this since the reviewer has dumped his review on the blogosphere. There are some absolutely first class institutions in the US (the National Park Service, The National Institutes of Health and the system of public and private universities are some of my favourites). The value of the latter two in terms of advancing scientific knowledge is partly due to the peer review system in all its forms. I think we should be careful to nurture these since they can be powerful weapons in the face of efforts at self-interested misrepresentation.
  49. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Thanks Marco; I haven't ever bothered to look at these things since normally you can get the data by other means. I'll be very interested to know how well these actually work... O.K. Tom. However the added benefit of including the 2010 data (melt index 2.0 in my analysis) and dropping 2000 is already made in my re-analysis (second of my reconstructions in my post above). So increasing the 2010 melt index a tad more won't have much of an additional effect. I'll do it anyway...
  50. Bob Lacatena at 03:16 AM on 8 May 2011
    Lindzen Illusion #2: Lindzen vs. Hansen - the Sleek Veneer of the 1980s
    I would point out that since angusmac has argued that Scenario C most closely matches observed temperatures, and therefore by his logic is the correct one to consider... ...he has in turn proven that actual CO2 emissions since 1998 have represented a rapid curtailment of trace gas emissions (Hansen's 1998 words). angusmac has successfully proven that we've already abandoned fossil fuels, and so there is no longer any danger of climate change. Let me be the first to congratulate everyone on a job well done. Humanity, and civilization, are saved by a simple and convenient re-interpretation of history. I wish I'd thought of that.

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