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

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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.


[NDT : les passages en italique sont en français dans le texte original]

Les émissions de carbone en France s’élèvent à 1,64 tonne par personne, contre 2,67 tonnes au Royaume Uni et 5,61 tonnes aux Etats Unis. Si un pays peut se targuer d’être vertueux, et faire la leçon aux autres pays développés, vous pourriez penser que ce serait la France. Loin de là, sous l’impulsion de Nicolas Sarkozy, la France s’est lancée dans un programme ambitieux de réduction des émissions de carbone. En présentant ces mesures, M. Sarkozy a déclaré : « Premier principe : tous les grands projets publics, toutes les décisions publiques seront désormais arbitrées en intégrant leur coût pour le climat, leur ‘coût en carbone’. » Ces mesures comprennent : l’engagement que tous les bâtiments construits en 2020 soient des producteurs nets d’énergie, l’interdiction des ampoules à incandescence à partir de 2010, des aides pour les acheteurs de véhicules les moins polluants, les conducteurs de véhicules les plus polluants étant au contraire taxés, et la construction de routes sera limitée pour favoriser les transports ferroviaires avec la technologie de pointe française du TGV ! Une taxe carbone est également envisagée. Ces propositions sont le fruit d’une intense série de discussions entre scientifiques et représentants de la société civile, dont des représentants d’organisations non-gouvernementales écologistes, d’organisations patronales et de syndicats. Ce processus, connu sous le nom de Grenelle de l’Environnement, a été décrit brièvement dans Nature ici (accès avec souscription), et un résumé par la presse des propositions d’actions de Sarkozy est ici.

Cependant, il y a une certaine résistance de la part d’un tandem bruyant de deux membres très décorés de l’Académie des Sciences française, Claude Allègre étant le plus médiatisé et tapageur des deux. Au cours des dernières années, Vincent Courtillot est apparu comme le fidèle compère d’Allègre –le Dupont de Dupond–, l’aidant à diffuser ses thèses, et en ajoutant aussi des personnelles. Tous deux sont membres de l’Académie des Sciences, et Allègre a reçu à la fois le prix Crafoord et la médaille Bowie. Allègre a une liste impressionnante d’articles ayant sujet à la Terre interne, et fut de plus le Ministre de l’Education Nationale, de la Recherche et de la Technologie sous le gouvernement Jospin. Courtillot –actuellement directeur de l’Institut de Physique du Globe de Paris (IPGP)– a un passé reconnu en recherche fondamentale sur le géomagnétisme, et est actuellement le président de la Section de Géomagnétisme et Paléomagnétisme de l’American Geophysical Union. Leurs opinions ont été largement (certains diraient même plus que largement) exprimées lors d’un colloque sur le rapport du GIEC tenu au printemps dernier à l’Académie (voir le numéro spécial “Evolution des Climats” de la Lettre de l’Académie des Sciences, ainsi que les rapports du Figaro, du Monde et de Libération). Qu’est-ce-que tout cela signifie ? Est-ce que les opinions d’Allègre et Courtillot sont fondées sur une profonde clairvoyance qui aurait échappé à la communauté de scientifiques qui ont consacré leur carrière entière à étudier le climat ? Voyons cela.


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Global dimming and global warming

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Readers might remember a minor kerfuffle in EOS (the AGU house journal) in February this year in which Gerald Stanhill claimed to find a paradox in the contemporaneous effects of global warming and global dimming (a long term reduction of surface solar radiation, mainly due to aerosols and clouds). The article attracted attention mainly because the paradox was claimed to “pose [a challenge] to the consensus explanation of climate change”.

Rather than point out the subtle confusions (between surface and tropospheric forcing, and local and global signals) here, I and two co-authors wrote a comment to the journal. After a number of avoidable and unavoidable delays, this comment (along with another one and a reply) have all now appeared in EOS (Nov 6 edition). By now of course, the original piece has been long forgotten and so the point in having the correspondence printed is unclear, but still…

For those that care, I’ll link our comment once it’s been posted on the GISS website (now available here), but the bottom line is clearly seen in the following figure:

That is, if you take all of the IPCC AR4 models (now called the CMIP3 ensemble), then over the twentieth century all of them show varying degrees of global warming, while at the same time they show significant global dimming. An earlier paper of ours had pointed to the aerosols (unsurprisingly) being the dominant cause for long term changes in dimming, but that changes in clouds on a decadal basis were responsible for much of the shorter term variability. Thus there doesn’t appear to be much ‘paradox’ left to worry about – both dimming and warming are seen in models and in observations.

Apologies for appearing to push my own papers here (not something we like to do particularly), but the published comment would have been better done as a blog post in February. There may be a lesson there….

BBC contrarian top 10

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There is an interesting, if predictable, piece up on the BBC website devoted to investigating whether there is any ‘consensus’ among the various contrarians on why climate change isn’t happening (or if it is, it isn’t caused by human activity or if it is why it won’t be important, or if it is important, why nothing can be done etc.). Bottom line? The only thing they appear to agree about is that nothing should be done, but they have a multitude of conflicting reasons why. Hmm…

The journalist, Richard Black, put together a top 10 list of sceptic arguments he gathered from emailing the 61 signers of a Canadian letter. While these aren’t any different in substance to the ones routinely debunked here (and here and here), this list comes with the imprimatur of Fred Singer – the godfather to the sceptic movement, and recent convert from the view that it’s been cooling since 1940 to the idea that global warming is now unstoppable. Thus these are the arguments (supposedly) that are the best that the contrarians have to put forward.

Alongside each of these talking points, is a counter-point from the mainstream (full disclosure, I helped Richard edit some of those). In truth though, I was a little disappointed at how lame their ‘top 10’ arguments were. In order, they are: false, a cherry pick, a red herring, false, false, false, a red herring, a red herring, false and a strawman. They even used the ‘grapes grew in medieval England’ meme that you’d think they’d have abandoned already given that more grapes are grown in England now than ever before (see here). Another commonplace untruth is the claim that water vapour is ‘98% of the greenhouse effect’ – it’s just not.

So why do the contrarians still use arguments that are blatantly false? I think the most obvious reason is that they are simply not interested (as a whole) in providing a coherent counter story. If science has one overriding principle, it is that you should adjust your thinking in the light of new information and discoveries – the contrarians continued use of old, tired and discredited arguments demonstrates their divorce from the scientific process more clearly than any densely argued rebuttal.

Find the error

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A colleague alerted me to a small town Nevada newspaper (The Ely Times) that has recently taken to publishing some rather egregious contrarian editorials and op-ed pieces about climate change (see e.g. here, and here).

Much in the spirit of what we attempt here at RealClimate (that is, public outreach and education), I figured I’d make an effort to inform the paper’s readers of the misleading nature of what they’re being told.

I decided to respond to their most recent editorial ‘Is CO2 a Poison?’ and other questions which wasn’t really a contrarian hit piece (i.e., what we’re used to seeing on the op-ed pages of the Wall Street Journal) so much as a confused mix of half-truths, irrelevant facts, flat-out errors, and, admittedly, some reasonable points (e.g. that there are challenging issues of fairness in how we go about achieving greenhouse gas emissions cutbacks). My letter was firmly critical, but, I felt, reasonably polite and fair.

I never received any correspondence from the editor (Kent Harper), and assumed that he had thus chosen not to publish my letter. So you can imagine my surprise yesterday in finding that, not only did the editor publish my letter, but in fact ran a contemporaneous and scattershot rebuttal along with it.

What I found particularly amusing was his denial that the original editorial contained any errors, as I had asserted. In particular, he challenged me to defend my assertion that he was wrong in claiming that the natural greenhouse effect leads to a warming of about 100F and that the correct number was closer to 60F.

Here is Mr. Kent, in his own words:

I asked Dr. Mann, in an answer to his e-mail, if the Wikipedia entry on the Greenhouse Effect (http://en.wikipedia.org/wiki/Greenhouse_effect) was incorrect. It said: “The Earth’s average surface temperature of 15 C (288 K) is about 33 C warmer than it would be without the greenhouse effect.” A celsius temperature of 33 degrees, converts to 91.4 degrees Fahrenheit, which I rounded off to “almost 100 degrees”.

Kent: if you are reading this, I would be more than happy to personally answer your question. But since you’ve decided to take our ‘discussion’ public anyway, I thought I’d rather use this as a ‘learning moment’ here at RealClimate. So I encourage our readers to provide their own answers to your question in the comments below.

Is the ocean carbon sink sinking? ¿Está desapareciendo el sumidero de carbono oceánico?

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The past few weeks and years have seen a bushel of papers finding that the natural world, in particular perhaps the ocean, is getting fed up with absorbing our CO2. There are uncertainties and caveats associated with each study, but taken as a whole, they provide convincing evidence that the hypothesized carbon cycle positive feedback has begun. [Read more…] about Is the ocean carbon sink sinking? ¿Está desapareciendo el sumidero de carbono oceánico?

The certainty of uncertainty

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A paper on climate sensitivity today in Science will no doubt see a great deal of press in the next few weeks. In “Why is climate sensitivity so unpredictable?”, Gerard Roe and Marcia Baker explore the origin of the range of climate sensitivities typically cited in the literature. In particular they seek to explain the characteristic shape of the distribution of estimated climate sensitivities. This distribution includes a long tail towards values much higher than the standard 2-4.5 degrees C change in temperature (for a doubling of CO2) commonly referred to.

In essence, what Roe and Baker show is that this characteristic shape arises from the non-linear relationship between the strength of climate feedbacks (f) and the resulting temperature response (deltaT), which is proportional to 1/(1-f). They show that this places a strong constraint on our ability to determine a specific “true” value of climate sensitivity, S. These results could well be taken to suggest that climate sensitivity is so uncertain as to be effectively unknowable. This would be quite wrong.

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Gee-Whiz Geoengineering

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Just about two years ago, Chemistry Nobelist, and atmospheric scientist Paul Crutzen opened a huge can of worms by suggesting that, since the world doesn’t seem to be getting its act together to significantly reduce CO2 emissions, it would be prudent to think about emergency measures in which we engineer ourselves out of the crisis by monkeying directly with the Earth’s solar radiation input instead of dealing with the CO2 content of the atmosphere. The specific proposal was to inject chemicals into the stratosphere that would form sulfate aerosols and hence block sunlight. Crude estimates suggest that the aerosol fix (if it is indeed a fix and doesn’t create more problem than it solves) is more technologically feasible than sci-fi dreams of sunshades at the Lagrange point. Not to say technologically feasible, necessarily, but not so far out as the other schemes. Crutzen’s idea, and related geoengineering proposals, have been discussed here on RealClimate. The subject is once more in the news, thanks to this chipper little op-ed by Ken Caldeira, which appeared in the New York Times this week.

Update: I just noticed that our original RealClimate piece was done before Crutzen’s article was published. You’ll find his article here (subscription not required).
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Younger Dry-as dust?

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The Younger Dryas is so called because it corresponds, in the pollen record from Europe, to the latest (i.e. youngest) appearance of the Dryas octopetala pollen, an alpine flower in regions that are now far from alpine. It marks a clear period towards the end of the last ice age when the warming trend of the deglaciation in Europe particularly was interrupted for a period of about 1300 years before it got going again. There were clear glacier advances during this time and the moraines can be seen very clearly all around Europe and Scandinavia.

The clues to what caused this remarkable, if temporary, turnaround have always lain in assessing its spatial extent, the exact timing and correspondence with other events. Two recent papers have shed some welcome and potentially controversial light on the subject.

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Sweatin’ the Mediterranean Heat

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Guest Commentary from Figen Mekik

This quote from Drew Shindell (NASA Goddard Institute for Space Studies, New York) hit me very close to home: “Much of the Mediterranean area, North Africa and the Middle East rapidly are becoming drier. If the trend continues as expected, the consequences may be severe in only a couple of decades. These changes could pose significant water resource challenges to large segments of the population” (February, 2007-NASA, Science Daily).

I live in Michigan, but Turkey is my home where I go for vacation on the Med. This year’s drought was especially noteworthy, so I would like to share some of my observations with you, and then explore the links between the North Atlantic Oscillation (NAO), Mediterranean drought and anthropogenic global warming (AGW).

The 10-hour flight from Chicago to Istanbul often inspires passengers to romanticize about Istanbul, both tourists and natives alike. Istanbul is the city of legends, forests, and the Bosphorus. It is an open museum of millennia of history with archeological and cultural remnants surrounded by green lush gardens. It is the place where east meets west; where blue meets green; where the great Mevlâna’s inviting words whisper in the wind “Come, come again, whoever you are, come!”

So you can imagine our collective horror as the plane started circling Istanbul and we saw a dry, desolate, dusty city without even a hint of green anywhere.
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