We’ve been a little preoccupied recently, but there are some recent developments in the field of do-it-yourself climate science that are worth noting.
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Climate Science
The Key to the Secrets of the Troposphere
Update: It seems that the UNFCCC background page referred to below has changed and the link no longer works – see table of contents.
A response from Justin Wood, writing to me from Australia after my previous post (cited with permission below), has prompted me to write a follow-up on the story of the greenhouse effect (GHE).
I wonder if you’ve seen this terrible description of the greenhouse effect on a UNFCCC background page? http://unfccc.int/essential_background/feeling_the_heat/items/2903.php
It actually says that incoming solar energy is ‘reflected’ by the planet’s surface ‘in the form of a calmer, more slow-moving type of energy called infrared radiation. … Infrared radiation is carried slowly aloft by air currents, and its eventual escape into space is delayed by greenhouse gases’ (emphasis added).Given your recent excellent explanation of the real physics on RC, I thought you might be interested! It’s downright disturbing that this silliness comes from such an important source; and I’ve found it repeated all over the place. (On that RC post, I would humbly suggest that the section on stratospheric cooling could helpfully be expanded to make that clearer?)
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Monckton makes it up
Guest commentary by Barry R. Bickmore, Brigham Young University
If you look around the websites dedicated to debunking mainstream climate science, it is very common to find Lord Christopher Monckton, 3rd Viscount of Brenchley, cited profusely. Indeed, he has twice testified about climate change before committees of the U.S. Congress, even though he has no formal scientific training. But if he has no training, why has he become so influential among climate change contrarians? After examining a number of his claims, I have concluded that he is influential because he delivers “silver bullets,” i.e., clear, concise, and persuasive arguments. The trouble is his compelling arguments are often constructed using fabricated facts. In other words, he makes it up. (Click here to see a number of examples by John Abraham, here for a few by myself, and here for some by Tim Lambert).
Here I’m going to examine some graphs that Lord Monckton commonly uses to show that the IPCC has incorrectly predicted the recent evolution of global atmospheric CO2 concentration and mean temperature. A number of scientists have already pointed out that Monckton’s plots of “IPCC predictions” don’t correspond to anything the IPCC ever predicted. For example, see comments by Gavin Schmidt (Monckton’s response here,) John Nielsen-Gammon (Monckton’s response here,) and Lucia Liljegren. Monckton is still happily updating and using the same graphs of fabricated data, so why am I bothering to re-open the case?
My aim is to more thoroughly examine how Lord Monckton came up with the data on his graphs, compare it to what the IPCC actually has said, and show exactly where he went wrong, leaving no excuse for anyone to take him seriously about this issue.
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Expert Credibility in Climate Change – Responses to Comments
Guest commentary by William R. L. Anderegg, Jim Prall, Jacob Harold, Stephen H. Schneider
Note: Before Stephen Schneider’s untimely passing, he and his co-authors were working on a response to the conversation sparked by their recent paper in the Proceedings of the National Academy of Sciences on climate change expertise. One of Dr. Schneider’s final interviews also addresses and discusses many of the issues covered here.
We accept and rely upon the judgment and opinions of experts in many areas of our lives. We seek out lawyers with specific expertise relevant to the situation; we trust the pronouncement of well-trained airplane mechanics that the plane is fit to fly. Indeed, the more technical the subject area, the more we rely on experts. Very few of us have the technical ability or time to read all of the primary literature on each cancer treatment’s biology, outcome probabilities, side-effects, interactions with other treatments, and thus we follow the advice of oncologists. We trust the aggregate knowledge of experts – what do 97% of oncologists think about this cancer treatment – more than that of any single expert. And we recognize the importance of relevant expertise – the opinion of vocal cardiologists matters much less in picking a cancer treatment than does that of oncologists.
Our paper Expert Credibility in Climate Change is predicated on this idea. It presents a broad picture of the landscape of expertise in climate science as a way to synthesize expert opinion for the broader discourse. It is, of course, only a first contribution and, as such, we hope motivates discussion and future research. We encourage follow-up peer-reviewed research, as this is the mark of scientific progress. Nonetheless, some researchers have offered thoughtful critiques about our study and others have grossly mischaracterized the work. Thus, here we provide responses to salient comments raised.
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Happy 35th birthday, global warming!
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) Una traducción en español está disponible aquí.
An icy retreat
) () Una traducción en español está disponible aquí.
The Montford Delusion
Guest commentary by Tamino
Update: Another review of the book has been published by Alistair McIntosh in the Scottish Review of Books (scroll down about 25% through the page to find McIintosh’s review)
Update #2 (8/19/10): The Guardian has now weighed in as well.
If you don’t know much about climate science, or about the details of the controversy over the “hockey stick,” then A. W. Montford’s book The Hockey Stick Illusion: Climategate and the Corruption of Science might persuade you that not only the hockey stick, but all of modern climate science, is a fraud perpetrated by a massive conspiracy of climate scientists and politicians, in order to guarantee an unending supply of research funding and political power. That idea gets planted early, in the 6th paragraph of chapter 1.
The chief focus is the original hockey stick, a reconstruction of past temperature for the northern hemisphere covering the last 600 years by Mike Mann, Ray Bradley, and Malcolm Hughes (1998, Nature, 392, 779, doi:10.1038/33859, available here), hereafter called “MBH98” (the reconstruction was later extended back to a thousand years by Mann et al, 1999, or “MBH99” ). The reconstruction was based on proxy data, most of which are not direct temperature measurements but may be indicative of temperature. To piece together past temperature, MBH98 estimated the relationships between the proxies and observed temperatures in the 20th century, checked the validity of the relationships using observed temperatures in the latter half of the 19th century, then used the relationships to estimate temperatures as far back as 1400. The reconstruction all the way back to the year 1400 used 22 proxy data series, although some of the 22 were combinations of larger numbers of proxy series by a method known as “principal components analysis” (hereafter called “PCA”–see here). For later centuries, even more proxy series were used. The result was that temperatures had risen rapidly in the 20th century compared to the preceding 5 centuries. The sharp “blade” of 20th-century rise compared to the flat “handle” of the 15-19th centuries was reminiscent of a “hockey stick” — giving rise to the name describing temperature history.
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A Eulogy to Stephen Schneider
We were greatly saddened to learn that our revered colleague Stephen Schneider passed away this morning.
We are posting a personal account by Ben Santer of Steve’s amazing accomplishments and contributions. Ben’s account provides a glimpse into what made Steve so special, and why he will be so deeply missed:
Today the world lost a great man. Professor Stephen Schneider – a climate scientist at Stanford University – passed away while on travel in the United Kingdom.
Stephen Schneider did more than any other individual on the planet to help us realize that human actions have led to global-scale changes in Earth’s climate. Steve was instrumental in focusing scientific, political, and public attention on one of the major challenges facing humanity – the problem of human-caused climate change.
Some climate scientists have exceptional talents in pure research. They love to figure out the inner workings of the climate system. Others have strengths in communicating complex scientific issues to non-specialists. It is rare to find scientists who combine these talents.
Steve Schneider was just such a man.
Steve had the rare gift of being able to explain the complexities of climate science in plain English. He could always find the right story, the right metaphor, the right way of distilling difficult ideas and concepts down to their essence. Through his books, his extensive public speaking, and his many interactions with the media, Steve did for climate science what Carl Sagan did for astronomy.
But Steve was not only the world’s pre-eminent popularizer of climate science. He also made remarkable contributions to our scientific understanding of the nature and causes of climate change. He performed pioneering research on the effects of aerosol particles on climate. This work eventually led to investigation of how planetary cooling might be caused by the aerosol particles arising from large-scale fires generated by a nuclear war. This clear scientific warning of the possible climatic consequences of nuclear war may have nudged our species onto a different – and hopefully more sustainable – pathway.
Steve was also a pioneer in the development and application of the numerical models we now use to study climate change. He and his collaborators employed both simple and complex computer models in early studies of the role of clouds in climate change, and in research on the climatic effects of massive volcanic eruptions. He was one of the first scientists to address what we now call the “signal detection problem” – the problem of determining where we might expect to see the first clear evidence of a human effect on global climate.
After spending many years at the National Center for Atmospheric Research in Boulder, Steve moved to Stanford in 1996. At Stanford, Steve and his wife Terry Root led ground-breaking research on the impacts of human-caused climate change on the distribution and abundance of plant and animal species. More recently, Steve kept intellectual company with some of the world’s leading experts on the economics of climate change, and attempted to estimate the cost of stabilizing our planet’s climate. Until his untimely death, he continued to produce cutting-edge scientific research on such diverse topics as abrupt climate change, policy options for mitigating and adapting to climate change, and whether we can usefully identify levels of planetary temperature increase beyond which we risk “dangerous anthropogenic interference” with the climate system.
Steve Schneider helped the world understand that the burning of fossil fuels had altered the chemistry of Earth’s atmosphere, and that this change in atmospheric composition had led to a discernible human influence on our planet’s climate. He worked tirelessly to bring this message to the attention of fellow scientists, policymakers, and the general public. His voice was clear and consistent, despite serious illness, and despite encountering vocal opposition by powerful forces – individuals who seek to make policy on the basis of wishful thinking and disinformation rather than sound science.
Steve Schneider epitomized scientific courage. He was fearless. The pathway he chose – to be a scientific leader, to be a leader in science communication, and to fully embrace the interdisciplinary nature of the climate change problem – was not an easy pathway. Yet without the courage of leaders like Stephen Schneider, the world would not be on the threshold of agreeing to radically change the way we use energy. We would not be on the verge of a global treaty to limit the emissions of greenhouse gases.
It was a rare privilege to call Steve Schneider my colleague and friend. It was a privilege to listen to Steve jamming on his beloved 12-string guitar; to sing Bob Dylan songs with him. It was a privilege to share laughter, and good food, and a good glass of red wine. It was a privilege to hear his love of science, and his deep passion for it.
We honor the memory of Steve Schneider by continuing to fight for the things he fought for – by continuing to seek clear understanding of the causes and impacts of climate change. We honor Steve by recognizing that communication is a vital part of our job. We honor Steve by taking the time to explain our research findings in plain English. By telling others what we do, why we do it, and why they should care about it. We honor Steve by raising our voices, and by speaking out when powerful “forces of unreason” seek to misrepresent our science. We honor Steve Schneider by caring about the strange and beautiful planet on which we live, by protecting its climate, and by ensuring that our policymakers do not fall asleep at the wheel.
Ben Santer
Revisiting the Younger Dryas
Guest Commentary by Chris Colose
One of the most intriguing and well-studied climatic events in the past is the Younger Dryas (YD), a rather abrupt climate change between ~12.9 and 11.6 thousand years ago. As the world was slowly warming and ice was retreating from the last glaciation, the YD effectively halted the transition to today’s relatively warm, interglacial conditions in many parts of the world. This event is associated with cold and dry conditions increasing with latitude in the North, temperature and precipitation influences on tropical and boreal wetlands, Siberian-like winters in much of the North Atlantic, weakening of monsoon intensity, and southward displacement of tropical rainfall patterns. RealClimate has previously discussed the YD (here and here) however there have been a number of developments in recent years which deserve further attention, particularly with respect to the spatial characteristics and causes of the YD.
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Information levels
Rasmus’ recent post on the greenhouse effect raised some interesting points concerning the technical level at which posts or other public communications should be written. This was a relatively technical article as these things go, eschewing the very basic ‘the greenhouse effect is like a blanket’ but not really approaching the level of a technical paper on the subject (no line-by-line calculations for instance). Nonetheless, there were complaints that was too much to be absorbed by the lay public, counter-arguments that making it too simple was patronising, as well as complaints that the discussions were not technical enough (for instance in explaining stratospheric cooling). In these discussions there are clearly the outlines of a common debate, and perhaps a way forward in the future.