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Les Chevaliers de l’Ordre de la Terre Plate, Part I: Allègre and Courtillot

18 Nov 2007 by raypierre

Translations: (Français)

France has a per capita carbon emission of 1.64 tonnes, compared to 2.67 tonnes for the U.K and 5.61 tonnes for the US. So, if anybody has earned the right to rest on their laurels and pontificate to the rest of the developed world about what they should be doing, you’d think it would be France. Far from it, under the leadership of Nicolas Sarkozy, France has embarked on an ambitious program of deeper carbon reductions. In introducing the measures, Sarkozy said "The guiding principle is that the cost to the climate — the carbon cost — will be integrated into planning of all major public projects, and into all deliberations affecting the public." These measures include: a commitment that all new buildings would be net energy producers by 2020, incandescent lighting would be banned by 2010, buyers of efficient vehicles would be subsidized, drivers of inefficient vehicles would be penalized, and road construction would be severely curtailed in favor of expanded rail travel using state-of-the-art French TGV technology. A carbon tax is also being seriously contemplated. These proposals are the result of an intensive months-long series of discussions with scientists and stakeholders such as environmental nongovernmental organizations, industry representatives, and labor union representatives. The process, known as Le Grenelle de l’Environnement, was described here by Nature (subscription required) and a summary of some of Sarkozy’s proposed actions was reported in the press here.

All the same, there has been some pushback from a vocal pair of highly decorated French academicians, Claude Allègre being the most prominent and noisiest of the two. In recent years, Vincent Courtillot has emerged as a reliable sidekick to Allègre — a Dupont to his Dupond — helping to propagate Allègre’s claims and adding a few of his own. Both are members of the Académie des Sciences, and Allègre has been awarded both the Crafoord Prize and Bowie Medal. Allègre has an impressive list of publications relating to the Earth’s interior, and besides that was Minister for Education, Research and Technology in the Jospin government. Courtillot — currently director of the Institut de Physique du Globe de Paris (IPGP) — has had a distinguished record of research on fundamental aspects of geomagnetism and is currently President of the Geomagnetism and Paleomagnetism Section of the American Geophysical Union. Their views were amply (some would say more than amply) represented at a symposium on the IPCC report, held last Spring at the Academie (See the issue "Evolution des Climats" of La Lettre de l’Académie des sciences, and press reports in Le Figaro, Le Monde, and Liberation). What does all this mean? Are the opinions of Allègre and Courtillot founded on some special profound insight that has escaped the notice of the community of scientists who have devoted entire careers to studying climate? Let’s take a look.

[Read more…] about Les Chevaliers de l’Ordre de la Terre Plate, Part I: Allègre and Courtillot

Filed Under: Climate Science, skeptics

Les Chevaliers de l’Ordre de la Terre Plate, Part II: Courtillot’s Geomagnetic Excursion

18 Dec 2007 by raypierre

Translations: (Français)

This article continues the critique of writings on climate change by Allègre and Courtillot, started in Part I . If you would like to read either post in French, please click on the flag icon beside the post title above.

Prelude: It’s the physics, stupid

…which of course is a paraphrase of Bill Clinton’s famous quote regarding the economy. We put the last word in small letters since we’ve learned that it is not a good debating technique to imply (even inadvertently) that those who are having trouble seeing the force of our arguments might be stupid. What we wish to emphasize by this paraphrase is the simple fact that the expectation of a causal link between increasing long-lived greenhouse gases (like CO2) and increasing temperature does not rest on some vague, unexplained correlation between 20th century temperature and 20th century greenhouse gas concentration.

The anticipated increase in temperature was predicted long before it was detectable in the atmosphere, indeed long before it was known that atmospheric CO2 really was increasing; it was first predicted by Arrhenius in 1896 using extremely simple radiation balance ideas, and was reproduced using modern radiation physics by Manabe and co-workers in the 1960’s. Neither of these predictions rests on general circulation models, which came in during subsequent decades and made more detailed forecasts possible.

Still, the basic prediction of warming is founded on very fundamental physical principles relating to infrared absorption by greenhouse gases, theory of blackbody radiation, and atmospheric moist thermodynamics. All these individual elements have been verified to high accuracy in laboratory experiments and field observations. For a time, there was some remaining uncertainty about whether water vapor feedback would amplify warming in the way hypothesized in the early energy balance models, but a decade or two of additional observational and theoretical work has shown that there is no real reason to doubt the way in which general circulation models calculate the feedback. When modified by inclusion of the cooling effect of anthropogenic aerosols, the theory gives a satisfactory account of the pattern of 20th and 21st century temperature change.

No other theory based on quantified physical principles has been able to do the same. If somebody comes along and has the bright idea that, say, global warming is caused by phlogiston raining down from the Moon, that does not make everything we know about thermodynamics, infrared absorption, energy balance, and temperature suddenly go away. Rather, it is the job of the phlogiston advocate to quantify the effects of phlogiston on energy balance, and incorporate them in a consistent way beside the existing climate forcings. Virtually all of the attempts to poke holes in the anthropogenic greenhouse theory lose sight of this simple and unassailable principle.

In a paper entitled "Are there connections between the Earth’s magnetic field and climate?" published recently in Earth and Planetary Science Letters, Courtillot and co-authors attempt to cast doubt on carbon dioxide as a primary driver of recent (and presumably future) climate change; he argues instead that fluctuations in the Earth’s magnetic field (partly driven by solar variability) have an important and neglected role. Like most work of this genre, it is carried out in an intellectual void — as if everything we know currently about physics of climate had to be set aside in order to make way for one new (or in fact not-so-new) idea. But the problems don’t end there. With the help of a Comment published by Bard and Delaygue (available here at EPSL or here as pdf) , we’ll expose a pattern of suspicious errors and omissions that pervades Courtillot’s paper. Sloppiness and ignorance is by far the most charitable interpretation that can be placed on this pattern.

[Read more…] about Les Chevaliers de l’Ordre de la Terre Plate, Part II: Courtillot’s Geomagnetic Excursion

Filed Under: Climate Science

Bubkes

26 Jun 2009 by Gavin

Translations: (Chinese (simplified))

Some parts of the blogosphere, headed up by CEI (“CO2: They call it pollution, we call it life!“), are all a-twitter over an apparently “suppressed” document that supposedly undermines the EPA Endangerment finding about human emissions of carbon dioxide and a basket of other greenhouse gases. Well a draft of this “suppressed” document has been released and we can now all read this allegedly devastating critique of the EPA science. Let’s take a look…

[Read more…] about Bubkes

Filed Under: Climate Science, Greenhouse gases

Live (almost) from AGU–Dispatch #4

13 Dec 2007 by raypierre

Ptarmigans are Back! Fans of the Sheep Albedo Feedback will remember these little fellows over on the right (photo credit: Ken Tape) from the immortal paper by Squeak and Diddlesworth on the influence of ptarmigan populations on the Laurentide Ice Sheet. In Session C33A on Wednesday, Ken Tape of the University of Alaska presented a paper on the influence of ptarmigan grazing on shrubbification of the Alaskan tundra. It seems that when there is deep snow cover, ptarmigan browsing is concentrated on those few willows that stick up above the snow. They eat the buds, which inhibits willow growth. These tall willows are the ones that have managed to benefit most by climate warming, but the ptarmigan provide a stabilizing feedback, up to a point. An interesting thing is the ptarmigan don’t like to perch. 98% of the winter buds within a half meter of the snow surface get eaten, but only 48% of the buds above that browse level. So, if the shrubs grow fast enough to get above the browse level, they can beat the ptarmigans. This seems to be happening more and more.
[Read more…] about Live (almost) from AGU–Dispatch #4

Filed Under: Climate Science

The Wall Street Journal vs. The Scientific Consensus

22 Jun 2005 by group

Translations: (Español)

We are disappointed that the Wall Street Journal (WSJ) has chosen to yet again distort the science behind human-caused climate change and global warming in their recent editorial “Kyoto By Degrees” (6/21/05) (subscription required).

Last week, the U.S. National Academy of Sciences and 10 other leading world bodies expressed the consensus view that “there is now strong evidence that significant global warming is occurring” and that “It is likely that most of the warming in recent decades can be attributed to human activities”. And just last week, USA Today editorialized that “not only is the science in, it is also overwhelming”.

It is puzzling then that the WSJ editors could claim that “the scientific case….looks weaker all the time”.

While we resist commenting on policy matters (e.g. the relative merits of the Kyoto Protocol or the various bills before the US Senate), we will staunchly defend the science against distortions and misrepresentations, be they intentional or not. In this spirit, we respond here to the scientifically inaccurate or incorrect assertions made in the editorial.

[Read more…] about The Wall Street Journal vs. The Scientific Consensus

Filed Under: Climate Science

Calling All Science Teachers

15 Jan 2007 by group

“An Inconvenient Truth,” the Davis Guggenheim documentary on global warming starring Al Gore’s presentation on the subject, provides an accurate, engaging, accessible, thought-provoking and (at times) even humorous introduction to one of the most important scientific issues of our time ( see our review of the movie). In some countries, viewing “An Inconvenient Truth” has actually become a required part of the science curriculum, and with good justification, we think. Given that the DVD is currently selling for $19.99 through Amazon.com, you’d think that the National Science Teachers’ Association ( NSTA) would jump at the chance to quickly get 50,000 free copies quickly into the hands of their members. Yet, when Laurie David, one of the producers of the film, made this offer to NSTA last November, it was summarily turned down on the grounds that the NSTA has a 2001 policy against “product endorsement” (as if Laurie David were trying to shop some new deodorant to high school science teachers). What in the world is going on here?

Before continuing with the history of NSTA’s bizarre decision, let us provide you with the most important information: Up to 50,000 US science teachers can receive a free copy of the DVD by filling out a simple request form here . The deadline for requesting your copy is January 18, so if you want a copy, take a few minutes to put in your request right away.
[Read more…] about Calling All Science Teachers

Filed Under: Climate Science

A phenomenological sequel

27 Nov 2007 by rasmus

Grading

Does climate sensitivity depend on the cause of the change?
Can a response to a forcing wait and then bounce up after a period of inertness?
Does the existence of an 11-year time-scale prove the existence of solar forcing?
Why does the amplitude of the secular response drop when a long-term trend is added?
[Read more…] about A phenomenological sequel

Filed Under: Climate modelling, Climate Science, Paleoclimate, Sun-earth connections

Books ’07

21 Dec 2007 by Gavin

We have a minor tradition of doing a climate-related book review in the lead up to the holidays and this year shouldn’t be an exception. So here is a round-up of a number of new books that have crossed our desks, some of which might be interesting to readers here.
[Read more…] about Books ’07

Filed Under: Climate Science, Communicating Climate

The Forecast in the Streets

28 Dec 2007 by david

The physical impacts of the global warming forecast can be bracketed with some degree of statistical confidence. Biological effects are more difficult to gauge, except in special cases such as the likely demise of polar bears that would result from the demise of Arctic sea ice. The societal effects, however, are nearly uncharted territory, at least to me. Perhaps the topic of global warming suffers from the same sort of cultural divide as university faculties, between the techies and the touchies; that is the sciences and the humanities. A new report (pdf) called The Age of Consequences, just released by the Center for Strategic and International Studies and the Center for a New American Security, tries to bring the social sciences, in particular history, geography, and political science, into the forecast of climate change in the coming century. It makes for fascinating if frightening reading. [Read more…] about The Forecast in the Streets

Filed Under: Climate Science

Back to the future

30 Apr 2008 by Gavin

Translations: (Español)

A few weeks ago I was at a meeting in Cambridge that discussed how (or whether) paleo-climate information can reduce the known uncertainties in future climate simulations.

The uncertainties in the impacts of rising greenhouse gases on multiple systems are significant: the potential impact on ENSO or the overturning circulation in the North Atlantic, probable feedbacks on atmospheric composition (CO2, CH4, N2O, aerosols), the predictability of decadal climate change, global climate sensitivity itself, and perhaps most importantly, what will happen to ice sheets and regional rainfall in a warming climate.

The reason why paleo-climate information may be key in these cases is because all of these climate components have changed in the past. If we can understand why and how those changes occurred then, that might inform our projections of changes in the future. Unfortunately, the simplest use of the record – just going back to a point that had similar conditions to what we expect for the future – doesn’t work very well because there are no good analogs for the perturbations we are making. The world has never before seen such a rapid rise in greenhouse gases with the present-day configuration of the continents and with large amounts of polar ice. So more sophisticated approaches must be developed and this meeting was devoted to examining them.

[Read more…] about Back to the future

Filed Under: Climate modelling, Climate Science, Paleoclimate

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