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Uncertain Times at the Royal Society?

Posted on 2 October 2010 by MarkR

Following complaints, the Royal Society has published a guide to climate science which has been produced with the help of 2 self selected “skeptics”. Traditional skeptical sources have enjoyed the release, including the Global Warming Policy Foundation (GWPF) and The Daily Mail, with the Mail quoting the Foundation’s Director;

"The Royal Society now also agrees with the GWPF that the warming trend of the 1980s and 90s has come to a halt in the last 10 years."

And gleefully reporting that the Royal Society “admits that there are ‘uncertainties’” - I remember a Professor who drilled "numbers mean nothing without uncertainties!" into students, so this shouldn't surprise most people with scientific experience!

The Intergovernmental Panel on Climate Change (IPCC) carefully includes them with all its statements. The Society report is worth reading if you have time but if you want detail then read the IPCC report: the two agree on everything they both cover.

The Society split simple statements into 3 sections: widespread scientific agreement, widespread consensus but active discussion, and ‘not well understood’. Let's dig up a few gleaming nuggets of knowledge.

Widespread agreement

  • 0.8 ± 0.2 °C warming since 1850.
  • Rise in CO2 caused by humans.
  • IPCC heating or ‘radiative forcing’ values.
  • Doubling CO2 causes 1 °C of direct warming, feedbacks are expected to add more.

Wide consensus but continuing debate and discussion

  • Solar heating less than 10% of CO2’s, but research is checking to see if it’s magnified somehow.
  • Doubling CO will cause 2-4.5 °C global warming (the IPCC says “likely to be in the range 2 to 4.5 °C with a best estimate of about 3 °C“), and IPCC global warming projections are repeated. 
  • Sea levels will rise at least at the rate they have been.

Not well understood

  • Models struggle with clouds, regional changes, and long term carbon cycle feedback.
  • Models don’t catch ice sheet breakup, so sea level rise they give is a minimum.


Non-model evidence for future sea level rise and global warming are ignored. This tends to suggest that doubling CO2 will cause 2-4.5 °C warming and new evidence suggests that sea level rise will be 100%+ more than IPCC estimates.

The GWPF concludes that;

"The UK now formally joins the ranks of denier nations,"

which seems remarkable from the Society's statement that;

"There is strong evidence that changes in greenhouse gas concentrations due to human activity are the dominant cause of the global warming that has taken place over the last half century. "

Finally, what of the GWPF’s claim that the Society now agrees global warming has halted? Another case of confusing short term trends, being ignorant of heat on Earth and seemingly based on;

"This warming has... been largely concentrated... from around 1975 to around 2000,"

but ignoring;

"The decade 2000-2009 was, globally, around 0.15 °C warmer than the decade 1990-1999."

Make of that what you will.   

NOTE: This blog post has been added to the list of rebuttals to skeptic arguments as the rebuttal to "Royal Society embrace skepticism".

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Comments 101 to 131 out of 131:

  1. Yeh - I'm not sure why you're pointing out that the science deals in uncertainty. This is a basic assumption of any scientist. That you should mention it suggests that you're trying to point out that no product of science is certain enough to act upon--the old religious "science has no answers!" gag. Of course, you may be reacting to the confidence many posters have here in the physics and evidence that supports AGW. Theory tries to find the explanation that best fits all the data and the physics. The AGW theory is the best fit, and no other comprehensive theory even comes close. Actually, no other comprehensive theory has been offered--even by so-called 'skeptics'. Instead, the AGW theory is attacked relentlessly (some might say 'robotically') by people who think they have the key to disintegrating it. That's all these people seem to be concerned about: disintegration--not alternative explanations. If you're sincere in your doubt about AGW, offer an alternative theory that takes into account as much evidence and physical law as AGW does. As far as the future is concerned, throwing doubt on models and predictions is a safe game, unless the game is being played with live weapons. If you trust your own analysis enough to say that the highest probability outcome for the next fifty years is not relatively rapid warming, then offer an alternative model that takes into account everything that climatologists take into account. If IPCC models were a kicker in a U.S.-style football game, then the IPCC would be up 3 points. Fifteen years ago, maybe not, because they were kicking from the 45 yard line. With the last fifteen years of data, the line of scrimmage has been moved to the 25. It's a game they don't want to win, though. You say "clouds," but it would help if you spread the problem out before using it club-like to attack AGW. Little or no proof or reasoning has been offered to support the idea that significant decreases or increases in cloud cover persisting over the range of climate is in the offing. I've seen a little discussion on albedo vs. insulation, and there doesn't seem to be a consensus as to the more powerful effect. Nothing in the last 30-40 years of warming suggests that a rapid change in cloud response to AGW is happening. Check the publication record. Yao and DelGenio conclude that the net feedback is positive. Indeed, the overall somewhat-less-than-significant-confident consensus is that clouds are a positive feedback. There is nothing in the physics, though, that would suggest a heavy and rapid response one way or the other. In other words, the likelihood that clouds could counter AGW is pretty slim. If they provide a negative feedback, it's probably going to be slight. It's more likely, based on current science, that they'll provide a slight positive feedback, much to our chagrin.
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  2. scaddenp at 11:02 AM, with regards to wind, your scenario assumes that the water vapour continues to be carried along by the wind at the surface. Consider instead the behavior of the wind in 3 dimensions where once it has absorbed the energy via the evaporation process it begins rising to be replaced by cooler drier air that continues the evaporation process. In your scenario, there would not be any such things as storms. With regards to clouds as a forcing, Roy Spencer in his latest paper proposes exactly that. He asserts that clouds act as a radiative forcing generated internal to the climate system, the problem having been the difficulty in identifying and separating such internally generated forcing from what he considers as a mixture of forcings and feedback. You ask the question, "How can clouds be a forcing?" I think to understand where Spencer is coming from, one has to be able to put aside any preconceived ideas that could cause one to ask that question, something Spencer thinks most people find difficult so deeply entrenched the conventional view is, as are most conventions.
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  3. JohnD, and your scenario, all ground air would be dry despite blowing over 100 kms of ocean which is not the case. I am trying to explain why on a basin-wide basis, the observed variation in evaporation with wind speed is lower than you seem to believe. Spencer use of "time-varying internal forcings" is somewhat novel and really is an exploration of the internal feedback mechanisms. This paper has been discussed before and I frankly doubt you can conclude anything concrete about feedbacks over longer term from the short term approach.
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  4. scaddenp at 09:44 AM,wrong, in my scenario the air would continually be absorbing moisture whilst it was present, even at night as we often see with saturated ground being dried on a windy night. The Spencer paper IIRC was discussed only prior to publication, with everyone quiet about since, unless I've missed any such discussion.
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  5. Johnd @102, I'm rushed here, but I think it suffices to say that the following, "once it has absorbed the energy via the evaporation process it begins rising to be replaced by cooler drier air that continues the evaporation process", is not correct. You do not say where this "cooler/drier air originates from. I'm not sure maybe you are taking about the entrainment of drier air from the free atmosphere into the planetary boundary layer as the boundary layer grows during the day. Look up "moisture flux divergence" which consists of two terms the "horizontal moisture divergence" and the "moisture advection" term". Moisture is most certainly advected by the horizontal wind field. Also, it is the "pooling" or convergence of moisture which oftentimes leads to the formation of thunderstorms (assuming an unstable profile and presence of a trigger mechanism which can lift the near-surface air "parcels" to the level of free convection). Anyhow, many factors govern transpiration and evaporation. And in order for evapotranspiration to continue does not require the moisture added to the air to be replaced by "cooler and drier air". See for example the Penman-Monteith (P-M) equation for governing variables. There are more sophisticated models, but the P-M is a good start. The contribution of ET to near-surface water vapor mixing ratio to the boundary layer is well documented and under ideal conditions can be significant.
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  6. Johnd @104, "The Spencer paper IIRC was discussed only prior to publication, with everyone quiet about since, unless I've missed any such discussion." They are probably busy validating his findings or trying to replicate them. I strongly suspect a comment (or perhaps even a refutation of his paper) is in the works. But be patient, good science takes time.
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  7. Johnd- but ability to evaporate decrease as water content rises. That is my point. Spencer's paper published now so the discussion will continue in the proper way - by scientists checking, validating and publishing. If it has really has merit, then it will be basis of more work; if not, it will be refuted and science will move on. No guesses where my money goes - if sensitivity was that low, we wouldn't have ice ages.
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  8. JohnD - also please explain how to change winds independently of temperature.
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  9. Baz, (#94), you ask: "What else could have caused a fairly-sharp upturn in temps?" That is a fair question but have you considered the fact that sharp upturns and downturns are the norm in "Climate Change". If you doubt me take a look at the ice core records that go back over 750,000 years. It is true that we are experiencing a "sharp upturn" but it is not unprecedented. The big difference is that this time the upturn could be caused by humanity's fondness for burning growing quantities of fossil fuel.
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  10. "The big difference is that this time the upturn could be caused by humanity's fondness for burning growing quantities of fossil fuel." - that and the lack of the forcings that dictated such change in the past. If comparing past 750,000 make sure you put instrumental record on same scale so you get a real understanding of "sharp". Though fortunately current change does not appear to be as rapid as NH suffered in Younger Dryas and Heinrich events that occur when coming out a glaciation.
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  11. gallopingcamel. Ah, I'm glad you said that! There are indeed sharp upturns in temp throughout the record, and all were natural. You're right, we're told that this time, this time, it is man-made (and we have a suitable cause). What intruiges me when I look at the graph of modern temps is indeed THAT sharp uptick. Would you agree that it would fit better if the temp slowly rose up, rather than it being quite sharp?
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  12. scaddenp at 10:40 AM, I'm not sure what you are getting at, or where you are coming from for that matter. Please explain.
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  13. Baz - just because sharp changes in the past were natural does not imply that sharp changes now are. You have to look at the causes. Are those causes from operating now. Nope.
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  14. Johnd - I think (and I may be wrong) that you are trying to imply that wind changes affecting evaporation is a climate FORCING. I am pointing out that wind change cannot be a forcing - wind changes can only be a response to temperature difference which in turn have other causes. It is my belief that you are confusing the causes of internal variability ("weather") with causes of climate trends.
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  15. scaddenp at 07:08 AM, you may be confusing me saying earlier that wind was a factor, a major factor. The 3 major factors directly driving evaporation are:- a) net radiation impinging on the water (heat input), b) vapour pressure (vpd) of the air passing over the pan . c) windspeed (ventilation). which are discussed in the paper titled:- Proceedings of a workshop held at the Shine Dome, Australian Academy of Science, Canberra 22-23 November 2004 Pan evaporation: An example of the detection and attribution of trends in climate variables
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  16. Baz(#111), If it turns out that rising CO2 is a major contributor to the recent upturn in temperatures we should be able to get a good estimate of "feedbacks". Are they negative or positive? There are plenty of people on this site who are convinced that the feedbacks are strongly positive but many well respected scientists (some of them with Nobel prizes) disagree. Sadly the question is well above my pay grade so I waiting to see what happens next.
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  17. GC - a published paper demonstrating net negative feedback would be more convincing. Any of these nobel laureates got one out? Net negative feedback would mean sensitivity of less that about 1.9. By contrast, we have all these papers measuring or modelling sensitivity by various means which show it higher. And for a longer view, Wally estimated the temperature for 2010 with surprising accuracy (all right he was lucky), in 1975 with an estimate of 2.8 (thats strongly positive feedback) though he also overestimated our emissions by a bit.
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  18. scaddenp (#117)' I will probably be told to take this issue to another thread but you did ask a fair question. Lindzen & Choi 2009 is a paper on the feedback question written by a Nobel laureate. The Lindzen paper is controversial but so are the dozen models cited by the IPCC.
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  19. Lindzen got a Nobel? News to me though he most certainly has produced outstanding work. Lindzen and Choi not being one them however. It has been specifically rebutted in the published literature and so far as I am aware, Lindzen has not responded. Furthermore, observational data would appear to directly refute it.
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  20. Although he's much-decorated I don't see anything about a Richard Lindzen Nobel prize in his bio: Richard Lindzen He does seem to have that reputation in some circles. Perhaps this was the shared award for IPCC work? Pretty ironic if so. I notice that the sites referring to him primarily as a Nobel laureate don't mention why he received his award. In any case, other than He Who Shall Not Be Named, no individuals were apparently included in the 2007 Nobel accorded to the IPCC: The Nobel Peace Prize 2007 was awarded jointly to Intergovernmental Panel on Climate Change (IPCC) and Albert Arnold (Al) Gore Jr. "for their efforts to build up and disseminate greater knowledge about man-made climate change, and to lay the foundations for the measures that are needed to counteract such change"
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  21. As well, it's worth remembering that the Nobel Peace Prize is not really intended in the same way as a Nobel for physics, or chemistry: “The said interest shall be divided into five equal parts, which shall be apportioned as follows: /- - -/ one part to the person who shall have made the most important discovery or invention within the field of physics ...” versus “The said interest shall be divided into five equal parts, which shall be apportioned as follows: /- - -/ one part to the person who shall have done the most or the best work for fraternity between nations, the abolition or reduction of standing armies and for the holding and promotion of peace congresses.” as the categories are somewhat weirdly presented at the Nobel Prize website.
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  22. doug_bostrom & scaddenp, You may be right about Lindzen's Nobel. I can't find specific information on the web. I got the idea from the BBC overseas service but on returning to the site today could find no reference to a Nobel prize. Next time I will do more checking. Please accept my apologies.
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  23. No need to apologize GC. We shouldn't really have to fact check everything we read. Doing a quick search for "richard lindzen nobel" and glancing at article teases etc., one could easily conclude he was a recipient. Unlike Monckton, if Lindzen's actual bio page is any guide the man himself is being very scrupulous not to convey the wrong impression, whatever his relationship w/the IPCC award may or may not be.
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  24. doug_bostrom (#123), Thank you for your kind comment. You make an interesting point about Lindzen. He seems to be very careful in what he says. For example, when asked what the future holds he says the temperature "may go up or may go down". The Royal Society has adjusted its position to reflect more uncertainty too.
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  25. Yes, GC. I think I said it here earlier, the Royal Society notably fails to bother providing readers of their update with a useful education on the notion of scientific uncertainty itself. Considering that the entire reason they're revisiting the topic is what's been described as poor communications about uncertainty, that's a bit sad. It's also a shocking waste of an opportunity to use wide press notice to help the public.
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  26. Doug, I agree completely. Somewhere along the line our educational systems are failing to help people learn how to handle scientific uncertainty. There are lots of consequences of this, but unfortunately those related to climate change are among the most pernicious.
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  27. GC @124, Lindzen was not being careful when he said that, if he indeed said that. Of course temperatures go up and down. Daily cycle, seasonal cycle, internal climate modes etc. Was the question about long-term global temperature trends? And just when is his iris effect going to kick in and manifest itself? If it has it is clearly not strong enough to be detectable in the global temperatures records (surface, radiosonde, satellite) MSU data. Sorry I am unimpressed by the lack of rigor here by Lindzen. IMHO, that statement is potentially grossly misleading (or at least has the potential to be misused) and unscientific. Very disappointing. Doug and Ned @125/126, I agree completely. It is going to be interesting to see how poorly parts of their "updated" document compares with AR5. It is sad that they were forced to kowtow to a small, vociferous element group within in the RS. But maybe not all is lost, someone I know (who is not a climate scientist) has had a look at the RS document and they still found the evidence for action compelling.... That said, it does not mean that the RS should change their document to reflect the current science and data.
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  28. #119 scaddenp at 15:03 PM on 6 October, 2010 Lindzen got a Nobel? News to me though he most certainly has produced outstanding work. Lindzen and Choi not being one them however. It has been specifically rebutted in the published literature and so far as I am aware, Lindzen has not responded. Well, he is a Nobel laureate, sort of. The 2007 Nobel Pace Prize went to IPCC and Al Gore, while Lindzen was a (reluctant) lead author of IPCC TAR WG1 Chapter 7 - Physical Climate Processes and Feedbacks. At least Mike Williams must have referred to this connection on BBC. I myself think this Peace Prize thing is pure shame. BTW, Lindzen has responded to critics. It was submitted to Journal of Geophysical Research on February 12, 2010.
    BBC One Planet - Climate change, pot plants and small frogs Nobel winner Richard Lindzen on being a climate change denier, and why office plants rock
    "American atmospheric physicist Richard Lindzen was one of the lead authors for the IPCC's third report on climate change. But he's not on this week's One Planet show to talk about the need for action on carbon emissions - quite the opposite in fact. Professor Lindzen believes the impact of human induced climate change has been exaggerated, and is urging political leaders to abandon their pursuit of costly carbon markets. His views may not be shared by the majority of the world's climate scientists, but Professor Lindzen is undoubtedly a formidable scientist - he's written (or co-authored) well over 200 scientific papers, and has been the recipient of numerous awards for his work on atmospheric physics. Debate is the foundation of science, so this week Mike questions the professor about why he feels the IPCC has become biased in favour of climate change, and hears his views on how humans have had a marginal impact on global warming. Also in the show, reporter Richard Hollingham looks to overcome his disdain for office pot plants - and in the process the One Planet plant gets a health check. Plus we hear about the world's smallest frog found in Malaysia."
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  29. Albatross (#127), That Lindzen quote is from my (admittedly suspect) memory. Lindzen was being interviewed on TV and one of the topics was what trends should be expected for global temperatures for the rest of this century. Lindzen said that the state of climate science was not sufficiently advanced to make such predictions with any confidence. By not radiating unjustified certainty Lindzen impresses me as someone who has humility and an open mind. Berenyi Peter, Thanks for that paper submitted to the GRL. It mentions problems raised by Trenberth and others before setting out to correct them. Clearly Lindzen is big enough to admit mistakes.
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  30. "Doubling CO will cause 2-4.5 °C global warming" Clearly you mean CO2 not CO. Also Joe Romm's post on this report at Climate Progress is worth a look. He argues the new report is dangerously conservative: "It doesn’t spell out simply and clearly what will happen if we don’t take action to reduce emissions nor does it spell out the plausible worst-case scenario (which is crucial to how individuals and societies actually make major decisions)."
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  31. Only a denier could read the RS report and deny that it supports the warmist position. And they will.
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