par Gavin Schmidt (traduit par Alain Henry)
Ce message s’écarte des pratiques habituelles de ce site pour commenter une pièce de pure fiction (au contraire des autres messages qui abordent le sujet sous un angle plus subtil). Le nouveau roman de Michael Crichton, « Etat d’urgence » raconte comment une ONG encourage la recherche scientifique sur le réchauffement global pour servir les objectifs de méchants éco-terroristes. Le roman nous amène inévitablement à la conclusion que le réchauffement global est un faux problème. Une leçon pour notre époque? Malheureusement, je ne le pense pas.
(suite….)
Comme le film récent « Le jour d’après », ce roman aborde des sujets et controverses scientifiques réels, mais il est également sélectif (et parfois erroné) quand il s’agit des faits scientifiques de base. Je voudrais discuter une sélection des thèmes liés au réchauffement global qui sont abordés entre les poursuites, les fusillades, les rites cannibales et autres prouesses. Le héros scientifique de Crichton est un professeur du MIT (Massachussetts Institute of Technology) devenu agent secret, qui étend ses tentacules intellectuels autour des autres personnages. Les sujets scientifiques sont abordés au cours de conversations et de séances de questions-réponses entre lui (et d’autres « bons ») et 2 autres personnages, un acteur (un type pas très brillant) et un avocat (un innocent dupé), dont les connaissances scientifiques sont plutôt limitées.
Donc, pour tous les acteurs et les avocats de par le monde, voici quelques éclaircissements.
Le sujets abordés par Crichton sont familiers à ceux qui travaillent dans ce domaine [les changements climatiques] et reviennent souvent dans les discussions. Certains sont réels et évalués correctement, tandis que d’autres ne sont que des diversions utilisées pour semer la confusion plutôt que pour éclairer.
Les premiers commentaires abordent la question de l’attribution de la tendance récente au réchauffement à l’augmentation du CO2. Un personnage suggère: « Si le CO2 n’a pas causé le refroidissement global entre 1940 et 1970, comment pouvez-vous être sûr qu’il soit responsable du réchauffement récent? » (paraphrasé de la page. 86 – NdT: l’édition française étant prévue pour 2006, les numéros de page se réfèrent à l’édition anglaise.) Les températures moyennes de l’hémisphère Nord ont effectivement baissé sur cette période, alors que les concentrations de CO2 continuaient à augmenter. Si les autres conditions étaient restées semblables, c’est un réchauffement qu’on aurait du observer. Mais sont-elles restées semblables? En fait, non. En réalité, le climat peut être influencé à la fois par sa variabilité interne comme par des causes externes (c-à-d autres que le CO2). D’autres « forçages » peuvent causer un refroidissement (par exemple les aérosols à base de sulfates et de nitrates, des changements dans l’utilisation des sols, l’irradiation solaire ou les aérosols volcaniques). Pour faire correspondre notre évaluation de ce aurait du arriver avec la réalité, il faut inclure TOUS les forçages (du mieux que nous pouvons). Même dans ce cas, une différence peut être causée par une variabilité interne (principalement liées aux océans, à l’échelle de plusieurs décennies). Dans les meilleures estimations actuelles, les changements globaux de température moyenne (y compris la période 1940-1970) correspondent de très près à l’effet combinés des forçages. Les impacts régionaux semblent être beaucoup plus liés à la variabilité interne (en particulier le réchauffement des années 30 dans l’Atlantique Nord). Toutefois, jamais personne n’ a pu montré que le réchauffement récent pouvait être reproduit sans prendre en compte l’augmentation du CO2 (et des autres gaz à effet de serre comme le méthane).
Ensuite, en puisant abondamment dans les données de stations météo, l’auteur mentionne un certain nombre d’enregistrements provenant de de stations particulières où la tendance de long terme est au refroidissement. Ils visitent en particulier Punta Arenas (à la pointe sud de l’Amérique), où (au grand plaisir de l’institution où je travaille ) les enregistrements de la station GISTEMP affichés au mur montrent une tendance de long terme au refroidissement (même s’il y a un léger réchauffement depuis 1970). « Et voilà votre réchauffement global » déclare un des héros. Je ne peux pas être d’accord avec ceci. Le réchauffement global est défini par la moyenne globale des températures de surface. Cela ne signifie pas que tout le globe se réchauffe uniformément (ce qui n’est évidemment pas le cas). (Mais ça n’empêche pas un des personnage de déclarer plus tard (page 381) : « Cet effet est probablement le même partout dans le monde. C’est pour ça qu’on l’appelle réchauffement global »). Si les personnages avaient visité la station toute proche de Santa Barbara Cruz Aeropuerto, le graphique affiché aurait montré une tendance positive. Est-ce que cela aurait été une preuve réchauffement global? Non. C’est seulement en amalgamant tous les enregistrements dont nous disposons (après correction pour les problèmes connus, comme discuté ci-dessous) que nous pouvons nous faire une idée de comment évoluent les moyennes régionales, hémisphériques ou globales. C’est cela, la signification de « réchauffement global. »
Crichton soulève ensuite le fait apparemment non reconnu (en tous cas par l’avocat) que l’intérieur de l’antarctique se refroidit (page 196), un thème discuté dans un autre post (refroidissement antarctique, réchauffement global?). C’est plus ou moins correct, étant donné les incertitudes évidentes dans les données de long terme pour l’intérieur du continent, mais, comme expliqué ci-dessus, un refroidissement local n’est pas contradictoire avec un réchauffement global.
Après cela, et de façon un peu plus troublante, nous avons quelques rappels plutôt trompeurs et sélectifs à propos du témoignage de Jim Hansen au Congrès en 1988. « Le Dr Hansen a surestimé [le réchauffement global] de 300% » (page 247). Ce témoignage conduisit effectivement à une forte augmentation de la prise de conscience du fait que le réchauffement global était un sujet important, mais pas parce qu’il exagérait le problème de 300%. Dans un article publié peu après son témoignage (Hansen et al. 1988), il présente des simulations pour trois scénarios de croissance des GES et des autres forçages. Le scénario A présentait une croissance exponentielle du CO2, le scénario B contenait une hypothèse plus modeste de scénario à politique inchangée (business as usual) et dans le scénario C, il n’y avait plus d’augmentation du CO2 après l’an 2000. Les scénarios B et C incluaient tous les deux une grande éruption volcanique en 1995. Très justement, les auteurs ne supposaient pas qu’ils savaient quelle serait la croissance des émissions de CO2. Ils présentaient donc plusieurs scénarios. Le scénario qui se trouve être le plus proche de la croissance réelle des forçages est le scénario B, à la différence que l’éruption du Pinatubo eut lieu en 1991 et non en 1995. Dans ce scénario, les changements de température de la décennie sont très proches de la valeur observée de 0,11°C/décennie (voir figure). Donc, à partir d’une bonne estimation des forçages, le modèle fit un travail raisonnable. En fait, dans son témoignage, Hansen ne montra que les résultats du scénario B et déclara clairement qu’il était le plus probable. L’erreur de 300% vient du « sceptique » bien connu Patrick Michaels, qui dans son témoignage au Congrès de 1998 effaça les deux courbes du bas pour donner l’impression que les modèles ne sont pas fiables.
Le Dr Hansen est encore cité (un peu hors contexte) en disant : « Les forçages qui déterminent les changements climatiques de long terme ne sont pas connus avec assez de précision pour définir les changements climatiques à venir. » Etant donné ce que nous venons de dire au paragraphe précédent, il est clair que sans une bonne estimation des forçages, les différences entre modèles peuvent être considérables. Il est communément accepté qu’une prévision exacte de l’évolution du climat dans les 50 ou 100 prochaines années est impossible. Le futur est en grande partie inconnaissable. Une nouvelle source d’énergie pourrait remplacer les combustibles fossiles, les gouvernements pourraient contrôler les émissions, ou nous pourrions avoir de nombreuses éruptions volcaniques. Il est donc beaucoup plus raisonnable de se demander ce qu’il adviendrait du climat si la concentration de CO2 doublait. Ou si ceci ou cela arrivait. Ces questions sont beaucoup mieux définies. La citation de Hansen est souvent utilisée pour soutenir que les modèles sont si peu fiables qu’ils sont inutiles pour aider à évaluer la situation. En fait, c’est le contraire – ce que Hansen dit, c’est que l’incertitude des modèles (par exemple la sensibilité climatique) est maintenant plus faible que l’incertitude sur les scénarios d’émission (c’est-à-dire l’incertitude sur les forçages, qui est responsable de l’incertitude des projections).
Ensuite, page 315, on trouve « dans les années 70, tous les spécialistes du climat croyaient qu’une période glaciaire allait arriver (et comme décrit en page 563, le professeur du MIT le pense toujours). Cette affirmation n’est pas correcte. Les pages de William Conolley sur ce sujet sont une lecture éclairante pour ceux qui voudraient plus d’information.
Un autre sujet qui revient souvent dans les discussions sur les données de température de surface est l’impact de l’effet « îlot de chaleur urbaine » (urban heat island effect). Il apparaît page 370. Il est incontestable que les centres de villes comme New-York sont significativement plus chauds que les régions avoisinantes. Ce sujet a été étudié en détail et des corrections sont faites pour en tenir compte dans toutes les analyses des évolutions de température globale. Pour voir s’il pourrait encore y avoir un effet résiduel dans les données corrigées, un article récent (Parker, Nature, 2004) examine les différences de tendance entre les conditions venteuses et sans vent. On sait que le vent diminue l’effet du réchauffement urbain. La tendance au réchauffement devrait donc être plus faible les jours venteux que les jours calmes, si cet effet restait important. Les deux tendances sont en fait quasi identiques. Il existe d’autres observations qui valident les ajustements de température de surface. Ce sont les océans, qui se réchauffent depuis plusieurs décennies. Même Richard Lindzen, habituellement un archi-sceptique sur ces sujets, a déclaré que « les augmentations de la température des océans soutiennent les données de température de surface » (Lindzen 2002). Une autre démonstration que les corrections sont suffisantes: sur le continent Nord-américain, où de nombreuses villes ont un effet de réchauffement du centre ville, la moyenne des données corrigées est en fait plutôt plate (page 88) – c’est-à-dire que le fort biais urbain des USA n’influence pas la moyenne régionale ou globale de température.
Un thème central du livre est l’augmentation du niveau des mers. Vanuatu reçoit une attention spéciale, car ses habitants se sentent à juste titre concernés par la transformation de leur île – très basse – en marécage. Le niveau des mers est toutefois quelque chose d’horriblement difficile à mesurer. Les jauges à marée donnent des données parasitées et sont en général situées sur les côtes continentales. La tendance globale estimée à partir de ces jauges est de 1,7 à 2,4 mm/an. Mais le niveau des mers n’augmente pas partout. La Scandinavie est toujours en train de rebondir depuis la dernière période glaciaire et la mer recule de ses côtes. Les observations par satellite (TOPEX / POSEIDON et JASON) peuvent donner une image globale. Elles indiquent que, même si l’augmentation moyenne des dernières années (2,8 mm/an) est significativement plus grande que la tendance de long terme estimée à partir des jauges de marée, les changements du niveau des mers sont en fait très dynamiques. On observe beaucoup de comportements différents, en particulier dans le pacifique, associés à la variabilité de El Niño, qui pourraient être reliées au fait qu’on n’observe pas d’augmentation du niveau des mers à Vanuatu depuis 40 ans. Curieusement, Crichton cite les données estimées des satellites pour prétendre que le taux d’augmentation n’a pas augmenté récemment (« [le niveau des mers] augmente rapidement, les satellites le prouvent. En fait, ils ne le prouve pas »), page 424. Comparer des données de satellites et des jauges à marée pose clairement des problèmes. Les données des satellites peuvent aussi avoir leur propres problèmes (voir les données MSU), mais les valeurs citées ne soutiennent en fait pas du tout l’affirmation du livre. Il serait toutefois plus juste de dire que les données obtenues par satellite sont compatibles avec une augmentation récente du taux, plutôt qu’une preuve qu’il existe effectivement.
Il n’y a que peu de véritables erreurs, mais, pour être généreux, elles ont probablement échappés à l’éditeur. Par exemple, page 187, « une température plus élevée entraîne plus de vapeur d’eau dans l’air et donc moins de nuages. » On peut supposer qu’il voulait dire que si les température sont plus élevées, l’humidité relative pourrait être plus basse (et il pourrait alors y avoir moins de nuage). A la page 368, « les régions agricoles sont plus chaudes que les forêts. » C’est probablement une confusion avec la question du réchauffement urbain, mais l’effet réel est le contraire: les zones agricoles ont un albédo plus élevé que les forêts, reflètent plus de radiations solaire et sont donc plus froides. En fait, même si ce n’est pas encore complètement quantifié, il semble qu’il y ait eu un terme significatif de refroidissement dans le budget global des 150 dernières années. A la page 461, « Le Groënland montre que, dans les derniers centaines de milliers d’années, il y a eu 4 changements abrupts de climat. » Plutôt 40, en fait. Et c’est probablement sous-évalué, puisque le Groënland ne peut garder des traces de changements qui ne seraient apparus que sous les tropiques.
A la fin du livre, Crichton nous donne son message. Il réitère les points principaux de sa thèse, c’est-à-dire que certains vont trop loin pour susciter un soutien (et j’ai quelque sympathie avec ceci) et que, parce que nous ne savons pas tout, nous ne savons en fait rien (ici, je me permets de ne pas partager son avis). Il donne aussi son estimation (~0,8°C) du réchauffement global pour le 21ème siècle et prétend que, puisque les modèles diffèrents de 400% dans leurs estimations, sa supposition est aussi bonne que les leurs. Ceci n’est pas vrai. L’ensemble des modèles actuels ont une sensibilité climatique moyenne d’environ 3°C pour un doublement des concentrations de CO2 (dans l’intervalle de 2,5 à 4°C) (réunion du GIEC de Paris, juillet 2004), soit une incertitude de 30%. Comme on l’a vu ci-dessus, les plus grandes incertitudes sur l’avenir sont l’économie, la technologie et le taux de développement. La cause principale de l’étendue de l’intervalle de 1,5 à 5,8°C donné par le GIEC pour 2100 est en fait la variété des scénarios utilisés. Sans meilleure information, si on supposait (incorrectement) que tous les scénarios étaient également probables, l’erreur autour de la moyenne de3,6°C serait de 60%, et non de 400%. Crichton suggère également que la plus grande partie de ses 0,8°C viendrait des changements dans l’utilisation des sols. C’est en fait extrêmement improbable puisque l’utilisation des sols a en fait un effet de refroidissement (comme discuté plus haut). Des simulations basées sur les lois de la physique sont en fait meilleure que les devinettes.
Finalement, dans l’appendice, avec une logique assez curieuse, Crichton compare le réchauffement global avec le mouvement eugéniste au 19ème siècle. Il soutient que, puisque l’eugénisme était étudié dans de prestigieuses universités et soutenus par des organisations caritatives, et qu’il en va de même actuellement pour le réchauffement global, ils doivent être liés d’un façon ou d’une autre. Vraisemblablement, l’auteur ne croit en fait pas que les recherches académiques soutenues par des fondations sont ipso facto mauvaises et malavisées, mais c’est l’impression qu’il nous laisse.
En résumé, je suis un peu déçu, en particulier parce que, durant la phase de recherche pour son livre, Crichton est en fait venu dans notre labo pour discuter certains des thèmes avec moi et quelques collègues. Je suppose que nous n’avons pas fait un très bon boulot. Jugeant de sa liste de lectures, la prose plutôt sèche des rapports du GIEC n’est pas à la hauteur de quelques textes plus piquants écrits par des sceptiques. Si RealClimate avait existé il y a quelques années, peut-être que tout se serait passé différemment.
Mise à jour: A la demande populaire, voici une version mise à jour du graphique original de 1998. mes excuses pour mon manque de compétences avec photoshop.
Mise à jour du 16 février 2005: Chris Mooney fait aussi un bon travail en vérifiant quelques notes de bas de page du livre de Crichton.
Fascinating. So glad that now I won’t have to read Crichton’s loopy book.
Many thanks for putting up this blog, it’s a tremendous resource.
Great site!
I’m sure you guys must have seen Crichton’s climate change lecture. See here. I think it gives you an insight into his position on this issue without having to delve through the book and the characterizations.
You mentioned computer simulations being published in journals. How much work is done on the validation of the models? IMHO, a model that is unvalidated doesnt deserve journal recognition. My eyes glaze over when I’m reading projections on GIGO models passed off as science. I do have utmost respect for papers that show actual measurements, references to understood physical processes, etc.
Response There is a vast literature on model evaluation, and a good place to start is the IPCC report, chapter 8 – William.
Re the 1940-1970 cooling:
There are several factors that might have impacted the 1940-70 cooling. The Second World War for one. The massive fire raids in Germany and Japan could be expected to inject a significant amount of particulate into the stratosphere. The war itself probably caused a net reduction in economic activity and emissions of CO2. I have read chattering about the injection of krypton-85 into the stratosphere from above ground nuclear testing as a potential climate impact, but am not qualified to evaluate that. Finally, the 1963 eruption of Agung in Indonesia was one of the 20th Century’s five climate-significant eruptions.
Of course I have filial bias (Eric Steig, one of the site contributors) but this is exactly the sort of analysis to which I will be so happy to point the readers of Crichton’s work that I will inevitably meet over the coming months. The challenge is to get this site in the media’s consciousness as the “go to” site for views on climate change subjects.
Re: the hansen scenarios graph – very impressive but isn’t it about time it was updated. I note that the last ‘observed’ reading appears to be in 1998. I’m sure it’s only coincidence but this was particularly warm ‘El Nino’ year.
regards.
Excellent tour de force. I spotted one thing that looks like an error though. You say:
On p368. “Croplands are warmer than forested lands”. This is probably a confusion with the urban heating issue, but the actual impact is the opposite – croplands have a higher albedo than forests, reflect more solar radiation, and are thus cooler.
He’s probably referring to Roy’s study here. A quote:
In addition, a warming effect was found along the Atlantic coast where croplands have replaced forests. Compared to forests, croplands are less efficient in transpiration, a daytime process where water evaporates from leaves during photosynthesis and cools the air.
Of course, the albedo changes are probably overidingly important. As is the release of CO2 from deforestation. Folks who are interested may want to read Matthews, 2004
Response: Thanks for pointing this study out. I think I’m still right, but I’ll look into it anyway – gavin
Well, it’s no surprise Crichton took the position he did. The anti-liberal crowd has been sourcing his spiel on scientific consensus as a refutation of climate change for a while now.
Sorry to be a nuisance but I did actually request an update on the Hansen graph. It is , after all, six years out of date.
Response: see above (I had to photoshop since I don’t have the original figure in a nice format) – gavin
In the NYT story about Crichton and this book:
He was particularly dismissive of the various computer models for climate change, saying, “You have to remember, I come from an experience where you can use a computer to make a photo-realistic dinosaur, and I know that isn’t real.”
Somehow, I fail to see the connection between understanding CGI and climate modeling. True, they both make use of computers but beyond that, I’m at a loss. Perhaps it’s taken out of context and he actually has more to say on the matter. It does seem to smack slightly of arrogance, however.
If Crichton really wanted to make a difference, he would do more to enlighten people about how science actually works. It’s not static. It’s not a cabal of evil-doers trying to get more from the government teat. It is largely a community endeavor to try to understand the truth.
There is a huge push in this nation to try to discredit uncomfortable facts and it seems even the once highly regarded arena of science is falling prey to PR driven reality. I applaud this site and its aouthors for their efforts to slow this trend.
“… Crichton actually visited our lab and discussed some of these issues with me and a few of my colleagues. I guess we didn’t do a very good job.”
I’m sure you did an outstanding job, just like you did with this article. Put the blame squarely where it belongs: on those who use your name and misrepresent your research to further their own agenda. Remember, the corporate polluters and their supporters don’t need to be right or accurate to win this debate. They only need to build the perception that the issue is so confused and contentious that the truth is ultimately a matter of personal opinion. That’s why investigations like “The Scientific Consensus on Climate Change” (Science, Dec. 2004) are important to show that most of the basic disagreements are nothing more than manufactured media spin.
“He argues, that since eugenics was studied in prestigious universities and supported by charitable foundations, and now, so is global warming, they must somehow be related.”
I haven’t read the book (or its appendix), so consider me ignorant, but –
Is this paraphrase of Crichton’s argument a fair characterization? Perhaps his point was that the simple fact that the research enjoys university and charitable foundation support does not necessarily mean that it will appear valuable in hindsight – or to put it another way, that “argument from authority” does not always lead one to truth.
If so, he’s correct in an absolute sense – however it’s a pretty good heuristic.
Response: I absolutely agree that “argument from authority” is not good science, but the converse (no good science comes from “authority”) is certainly not true, and this is what is implied in the appendix (It’s short, just sneak into Barnes and Noble and read it). – gavin
Hmmm. So Crichton cherry picks the data, twists the facts, and actually makes stuff up. That must be why he’s getting so much attention on Fox News. (After all, it takes one to know one…)
Seriously, as a journalist (and a professor of journalism), I’m wondering whether scientists think they should even bother responding in a very public way to Crichton. It seems to me that you are damned if you do and damned if you don’t. If you respond by going on television, you increase his publicity and book sales. (And the broadcast media will play it in typical “he said, she said/global warming: yes or no?” fashion.) If you don’t – if, for example, you simply stick to the blogosphere, like this – his big lie will stand unchallenged. In other words, he wins no matter what, because he is a celebrity and the rest of you are, well, mere scientists doing serious work. (At least you guys are still trusted more than we journalists are…)
My opinion: Damn the torpedoes, full speed ahead. Blow him out of the water! (And try to forget that even if you win the battle you’ll probably still lose the war, at least on television.)
Tom Yulsman, Center for Environmental Journalism, University of Colorado
Crichton also spends quite a bit of space arguing that Greenland is cooling, rather than warming. The recent Arctic Climate Impact Assessment has an impressive figure showing that the area of Greenland experiencing summer melt is dramatically larger in 2002 than in 1992. (see http://amap.no/acia/GraphicsSet2.pdf at page 10). Can you shed some light on this subject.
Thanks.
I think you are being rather too hard on Crichton. He is a novelist not a scientist. I like many thousands of others loved Jurassic Park but it is of course filled with the most arrant nonsense. I don’t mean the DNA retrieval or even the species resurections. I mean all that stuff about chaos theory. In Shakespeare and Victorian adventure novels there is often a seer or witch who predicts the future to give the reader a warning of the impending catastrophy. In Jurassic Park Crichton uses chaos theory in just this way. There is still some of this in the movie. The Jeff Goldblum character can see that the park will fail because of MATHEMATICS. Not because of sabotage or bad construction. His math tells him the dinosaurs must get out.
Using the math of chaos theory to predict actual outcomes in the real world without any measurements is a truly goofy idea. Yet as a drammatic device its pretty effective.
When I was little every week I saw a movie about how nuclear war or waste would cause people to shrink (or enlarge). A whole generation learned that atomic enegy brought mutant monsters. Maybe that’s why nuclear power is so unpopular. I don’t know but I don’t see a ready solution. Movies and books need drama. Crichton is not interested in climate science so as to teach accurately. He wants only enough to supply a veneer of verisimilitude. All we can hope is that no one takes pop culture as their only source of scientific information.
Yes, but the polar cooling does flatly contradict the climate models that are the basis of the global warming hypothesis. Not only is the bulk of the Antarctic continent cooling, but temperature stations all around the Arctic rim have shown no overall temperature rise since the late 1930s.
See Godhab Nuuk, Tromo, Ostrov Dikson, Ostrov Kotel, Dzardzan, and others.
There’s no way out of it: if the greenhouse gas theory were correct and the climate models were really modelling the “real climate” then the high latitudes would be warming the fastest. But they aren’t. They are barely warming at all on timescales where real climatic variation counts (and by that I mean less than 50 years).
Also to claim a warming on the basis of a multi-decadal oscillation back to the 1970s (when the temperature had been falling since about 1940) as some sort of significance, is beyond risible.
The 1930s warming wasn’t just visible in the North Atlantic but as far away as Cape Town, South Africa (which also shows the 1930s, not the 1990s, as the warmest decade, natch), but Punta Arenas, Christchurch, New Zealand, Quelimane, Indian Ocean
So the reference to the warming of the 1930s being limitied to the North Atlantic is simply false.
Response: Look at all the data instead of just cherry picking the stations that agree with your prior hypothesis. To make things easier for you I have the calculated the global anomalies (w.r.t 1951-1980) for the 1930’s and the 1990’s from the same data set that you quote. It’s readily apparent that the 1990’s warming is significantly more extensive than for the 1930’s.
As for your other point, I doubt that pointing to a climate model that shows Antarctic cooling will be sufficient, but it might help… – gavin
The book seems to be a “Mary Sue”. From http://nielsenhayden.com/makinglight/archives/004188.html:
MARY SUE (n.): 1. A variety of story, first identified in the fan fiction community, but quickly recognized as occurring elsewhere, in which normal story values are grossly subordinated to inadequately transformed personal wish-fulfillment fantasies, often involving heroic or romantic interactions with the cast of characters of some popular entertainment. 2. A distinctive type of character appearing in these stories who represents an idealized version of the author…
I think Crichton’s book goes in a direction opposite responsible laypersons should go. Scientists rightly have to worry about false positives – claiming something (like global warming) is happening, when it is not, or their reputation might be harmed (and no one will believe them when they call wolf next time). They need the magic .05 significance level, or something approaching it. Laypersons, such as Crichton, his readers, and myself, should be worried more about avoiding false negatives: doing nothing to abate global warming, when in fact it is happening. We do not need high scientific proof to start screwing in compact fluorescent bulbs, low-flow showerheads, etc. In fact I have reduced my greenhouse emission about at least 3/4 and am saving $hundreds per year (we reduced by 1/3, then went on 100% wind power from Greenmountain Energy). Energy experts, such as Amory Lovins, figure we can reduce our energy consumption in the U.S. by 3/4 without lowering productivity or living standard with, off-the-shelf technology and conservation habits. So for laypersons a true negative (we do nothing to reduce GH emissions, and GW is not happening) would be much worse economically & re other environmental problems, than a false positive (we abate global warming, when it is not happening).
I can’t imagine Crichton’s thesis of people using a “false global warming” for evil ends. What I see is people thwarting action to address a highly probable “true global warming” for evil ends. What I find in daily life is that very few people know what global warming is (many confuse it with the strat. ozone hole), and those that do know about it, think it has been disproven. I very rarely meet anyone who thinks it’s a problem, and even more rarely meet anyone who is actually trying to reduce their greenhouse emissions – even those easy steps that save money.
I’m happy I found this site, and am happy bonafide scientists are addressing errors of the skeptics, who seem to have little concern about avoiding false negatives (or our biological and economic welfare) and are excessively fearful of false positives for whatever reasons.
To TangoMan who wants to see model validation. The essential problem with this approach — to validate a model you need experimental results. Well, the experimental results take time to develop, and the future world is the only validation lab we have. And by that time, it’s too late. Kind of a catch-22 we have here.
Thank you for putting together such an exhaustive answer to Crichton’s rubbish about global warming. Though not specifically in relation to Crichton’s book, http://www.info-pollution.com/myths.htm will also be a useful tool in taking it apart: it has a large section about DDT and the so-called DDT “ban” which allegedly led to millions of deaths, another dubious claim that Crichton twists in much the same way as climate change.
Beyond his pseudoscience, I think I was a bit more saddened by his rhetorical “dirty tricks”…. the old canards that are always tossed out against anybody arguing the pro-environmental position. We’ve seen it a zillion times, yet Crichton acts like putting it in print *one more time* will make it less false.
For instance, his stand-in narrator asserts that “conserving nature is foolish / dishonest, since extinction and change are constant!” Thus writes a former M.D., presumably dedicated to the conservation of human life – what a foolish endeavor since extinction and change are constant! I also assume that Michael Crichton M.D. was paid for his services with money, which he put in a bank account – again, what a silly thing to do in a world where nothing matters since change and extinction are constant!
Another low-blow he uses in SoF is that “by spending money on the environment, you’re not giving it to the poor! – Well -. yeah. That’s how money works. By spending it on ANYTHING, you’re not giving it to the poor. Same thing goes for military spending (remember what Eisenhower said?), the space program, publicity campaigns for Crichton’s latest hack-work, and lots of other things that get way higher funds than environmentalism. So why single that out? Simple: to try to get the presumed bleeding-heart supporters of environmentalism so consumed with guilt that they’ll abandon it. As one newspaper reviewer put it, the author’s wise to cloak his anti-environmentalism in the rhetoric of a third-world do-gooder, but rest assured that Red Riding Hood can see the wolf’s tail sticking out of grandma’s robe.
To Gavin,
Whereever did you get that data? If I point my browser at the warmest points on the Arctic rim (according to both your graphs), the nearest stations with records that show the 1930s all show the 1930s as being warmer than the 1990s.
Response: It’s from the GISTEMP site – the same place you got the station data, and it comes from the combined GISS+Had/Reyn analysis. http://www.giss.nasa.gov/data/update/gistemp/maps/ -gavin
I did not compare them with the 1950-1980 records but with each other, because I was establishing that the 1930s were warmer on the Arctic Rim than the 1990s. And they were. Practically every station record from the high Arctic shows this.
I note also, that you don’t even bother to tackle the issue of the statement that the 1930s warming was purely a North Atlantic warming because it’s clearly untrue. That warming was shown in records all around the globe.
As for your link to a climate model predicting the Antarctic may be cooling because of greenhouse gases, my reaction is similar to Homer Simpson: “Models! Is there anything they can’t do?”
In response to comment #16 (“He is a novelist not a scientist”). I think you are too easy on Crichton. He is also a popular public speaker who loves to make up “facts” to suit his particular agenda. A good example is his well-known statement that “DDT is not a carcinogen and did not cause birds to die”. It is true that DDT has not been demonstrated to be carcinogenic except at very high levels, but this is true of most suspected carcinogens — most data is clinical, not epidemiological. And the evidence that DDT causes bird egg shells to thin, resulting in lower birth rates, is overwhelming.
In response to #22, saying “Models! Is there anything they can’t do?”
Climate models are simply computer code that incorporates radiation and the physics of fluids on a rotating sphere. There is nothing magical about them, and there are a lot of things they “can’t do”. The point that some models show Antarctic cooling is simply that Antarctic cooling is therefore physically plausible in an otherwise warming world. In any case, this entire discussion is a bit of a red herring because the degree of cooling appears, from the data available, to be quite limited in spatial extent and temporal duration. Making a big deal about this is like pointing to the bad economy in say, Louisiana this week, and concluding that the country’s economy as a whole is going down the tubes.
A response to comment #19 from Lynn Vincentnathan “that very few people know what global warming is (many confuse it with the strat. ozone hole), and those that do know about it, think it has been disproven. I very rarely meet anyone who thinks it’s a problem.”
Actually, polling shows quite convincingly that the vast majority of Americans accept that the globe is warming and that humans are at least partly responsible. For details on this polling data – which have been consistent since 1997 – see “A Myth about Public Opinion and Global Warming”. The bottom line is that for seven years running, between 70 and 75 percent of Americans believe that global warming is a reality and are concerned about it.
This suggests that maybe the news media are not doing as bad a job in reporting on this subject as is frequently argued, and that greater public knowledge of the scientific basis of the issue won’t necessarily lead to better policies. Perhaps prompting greater public support for action will require a re-framing of the debate, as Roger Pielke, Jr., frequently argues, from “global warming: yes or no” to the benefits we might derive from tackling energy issues regardless of whether climate change is a problem. Many if not most policy prescriptions recommended for dealing with climate change are so-called “no regrets” policies. And if these policies were actually discussed publicly in that way (as being beneficial for many reasons other than mitigating global warming) perhaps we’d get out of the trap that Michael Crichton and his ilk continue to set for us.
— Tom Yulsman, Center for Environmental Journalism, University of Colorado
A lot of the modeling depends on what exactly you assume – for example if it is a trend model if you take a moment in time and track it back to a previous low or high then you will get the upward or downward trend. so if I say now to 1970 I can get an upward trend if I use now till begining of the industrial revolution I might get a flat line. You could take a random graph and draw such a trend.
I notice such graphs tend to start in 60-70 and end now coincidentally that is also close to a low point is it not?
Anyway – results with more extreme results are more likely to get attention, and fit better with likely researchers mindsets for “usable data”, both for those trying to prove no effect and those trying ot prove an effect.
Having said that a strong study should stand on its own and if the studies are reliable it should be possible to list a basic set of major assumptions that differ between them and explain how they effect the results. I am also disinclined all things being equal to argue that scientific consensus is outright false unless there is hard evidence with which to do so.
> For lack of better information, if we (incorrectly) assume all the scenarios are equally probable, the error around the mean of 3.6 degrees is about 60%, not 400%.
This assumption is of course the most favourable possible for your own conclusion jsut like he chose the most favourable possible for his own conclusion – actually your 60% and his 400% are the same. Your scale after-all does not even go up to 400% so it would be highly unlikely a person would sit there and thing 400% difference refers to a 400% difference on either side of the mean. (still – you are welcome to point out another perspective)
> Laypersons, such as Crichton, his readers, and myself, should be worried more about avoiding false negatives.
The problem is a layperson can do nothing about global warming by himself, only collectively can anything be done and we are doing nothing really. Anyway it is a false comparison to compare old temperatures with new temperatures when asking “wht should we do” you need to compare “our solution” with “their solution” If you are advocating a political strategy you need to accept current proposed strategies will probably still result in the majority of the global warming predicted in the ordinary scenario (if not all of it – a point which I can argue if you like).
> “argument from authority” is not good science
It is a hard thing to say but eugenics is not “bad science” in and of itself. It is just immoral and dangerous, rather like nuclear weapons. Genes are in part responsible for intelligence and one could theoretically breed for intelligence, we reject it for social rather than scientific reasons. Similarly Global warming does not appear to be bad science but are we really willing to do what it takes to do anything about it?
Gavin:
Interesting and informative critique of Crichton’s criticism of global warming theory. I am far from sold on this theory so I appreciate your analysis. Thanks for updating the graph to include current numbers. My interpretation is that you have to back off the statement that so far the data follows scenario B the best. It looks to me like the trend is more towards the lower end of the prediction scenarios, either B or C. But your major point about the 300% off statement is right on the mark. As an earlier commentor pointed out Crichton makes great hay with his consensus argument. But sometimes consensus just means that there is a consensus of skeptics (e.g., Wegener’s theory of continental drift was proposed in 1912 based on continent shapes but was not widely accepted until 50 years later because the smoking gun – deep sea rifts – hadn’t been discovered) or there is consensus because the data is overwhelming (e.g., descent with modification).
As I understand complex modelling it uses iterative techniques such as monte carlo simulations–Can it also use Covariance Structure Modelling? (LISREL or AMOS for example); is it possible to determine the amount of variance explained in a complex model from the independent variable(s) attributed to human involvement? or is this even a valid question. Is there a text recommendation anyone can provide that would shed light on these questions? Thanks in advance.
Art,
As for your link to a climate model predicting the Antarctic may be cooling because of greenhouse gases, my reaction is similar to Homer Simpson: �Models! Is there anything they can�t do?�
And you would prefer that we predict changes in the earth’s climate… how? Examining chicken entrails? Comments like that- dismissing the entire scientific process- suggest that you are not interested in refining errors in that process, but (like Crichton) in wrecking it somehow. Why? Because, deep down, you know what having virtually all of the experts disagree with you means- it means that you are wrong. So, casting aspersions on the process is (presumably) the best outcome you can hope for.
Normally, Id refrain from considering (let alone attacking) motive in discussing science, but I think an exception must be made with creationists and other science-defying ilk such as yourself. When it is so easy to infer that your goal isn’t adding to scientific knowedge, I see no reason to even begin a scientific discussion of the merits. And, the wisdom of this position is seen in watching your argument change from ‘what about these specific data’ to ‘models are useless’.
Wu
Gavin Schmidt writes, “He (Crichton) also gives us his estimate, ~0.8 C for the global warming that will occur over the next century and claims that, since models differ by 400% in their estimates, his guess is as good as theirs. This is not true.”
I agree. That’s not true. Michael Crichton’s guess of ~0.8 degrees Celsius for the 21st century is far, far better than the IPCC projections of 1.5 to 5.8 degrees Celsius (from 1990 to 2100). I discuss this fact on my website (my own prediction is for ~0.7 degrees Celsius warming in the lower troposphere):
A review of IPCC projections versus historical and likely future trends
The IPCC projections are completely unrealistic, in part because:
1) They include completely unrealistic projections for future atmospheric methane concentrations, and
2) They include unrealistic projections for future CO2 emissions, and for future CO2 atmospheric concentrations.
Mark Bahner (environmental engineer)
Response: So your point is that working on no information (i.e. Crichton), is better than working with the limited information that we have? Curious. Can improvements in information improve forecasts? Yes. But arguing that because we don’t know everything, we might as well pull a number out of thin air is a little odd. – gavin
“Plot is a literary convention. Story is a force of nature.”–Teresa Nielsen Hayden
I think responding to Crichton is very important. Stories are one of the most important ways humans understand the world. So far the most popular stories about climate are very conservative; based in the common fear of change, which is a fair way of describing both all of Crichton’s work I have read, and disaster movies like The Day After Tomorrow. It probably isn’t enough to respond critically, though; criticism never catches up with history. And this is a new story. One of the newest elements is the relatively quick emergence of global scientific consensus–what does that mean? And while ecological problems in the context of a vast coherent economy are not new–Rome knew them, IIRC–the scale is unprecedented. Equally, the speed with which information is moving around the globe is unprecedented.
Yet there has been oddly little art addressing this. Oh, there’s Bruce Sterling’s Viridian list and website, there’s Worldchanging, and there has been political debate. But in terms of serious art on the subject…nothing is coming to mind, though a world under climate change has been a background of several SF novels. For a long time, I’ve been comparing the situation with the science-fictional scenarios of world-wide disaster I grew up with. And the differences are so striking I think they deserve comment. It’s not a lone scientist, offering the warnings. It’s not even a group of scientists, or outcast scientists. Though there are scientific critics of the IPCC’s work, there are no more climatologists among them–the last holdout, Lindzen, wrote a chapter in the Third Assessment (he still claims climate change probably will not be a problem, however.) And heroic businessmen? Nowhere to be found, though the current CEO of BP is fairly reasonable about the issue. Villanous businessmen and politicians, on the other hand, we have in large numbers, most notably US Vice President Dick Cheney. And European politicians are taking the lead. Who’d’a thunk it? Japan, too, though perhaps that is not so surprising. Russia? Putin the Stalinist? Wow, my head is spinning.
Which all sounds pleasantly perplexing, at least when I am not quaking in my boots. But I think the differences bear some examination. The people who wrote those novels had what are in retrospect, big gaps in their thinking and I think those gaps are the gaps in our culture’s thinking. What else have we missed?
By the way, economist Brad Delong, a popular blogger, has given you a notice. Expect your readership to rise, along with the crackpot level.
Regarding post 26:
“The problem is a layperson can do nothing about global warming by himself, only collectively can anything be done and we are doing nothing really.”
This does not follow. Collective action is made up of the actions of individuals. You and I _can_ do something about global warming – we can reduce how much CO2 we pump into the atmosphere. How? Avoid using cars; use renewable resources for energy production (solar, wind, tidal, etc); lobby/irritate your government into supporting/pushing/subsidising renewable energy resources. The list really does go on and on.
We (as individuals!) cannot afford to cop out with the attitude that “if some huge quantity of people don’t do anything about global warming then we’re screwed, and noone else seems to be doing anything so I won’t either”.
These are thing you and I can do now, today.
Michael Crichton did not convince me of the premise that man-made Global Warming is a myth perpetuated by environmental Gods determined to control our “vision of the world”, it was hysterical environmentalists themselves who convinced me to question their motivations and facts when I discovered after twenty years of fear-mongering that our world was not going to perish in an Ice Age.
I grew up with the theory that it was the Ice Age we should “beware” however, since this did not happen, the environmentist movement created a “Global Warming” theory we must all “beware”. I liken today’s hysteria to the time when man believed the earth was flat and if we sailed to the end of the horizon we would fall off the Earth and die. That said, I imagine we will still be around long after the Ice Age/Global Warming fears have disappeared.
The problem with the enviromental movement is it’s use of unfounded theories to panic the population into believing false information.
The fact is climate changes and Mother Nature is bigger than all the scientists and all the environmentalists on the planet, we would do service to her in recognizing this fact. Scientist and environmentalist cannot predict the future nor climates. Nature changes and adapts regardless of human existance, our human desire to micro-manage our planet is a waste of valuable time and resourses.
Perhaps undertanding how we can adapt to nature’s power is an approach long overdue. Having lived “close to nature” most of my life I have come to understand that at any given time nature can kill me in an instant, I do not need environmental Ice Age/Global Warming fears to instill such knowledge.
Further to the Hansen graphs. I had a quick look at Hansen’s abstract. It said “Scenario A assumes continued exponential trace gas growth, scenario B assumes a reduced linear linear (sic) growth of trace gases, and scenario C assumes a rapid curtailment of trace gas emissions such that the net climate forcing ceases to increase after the year 2000”
From that form of words I would assume, as Patrick Michaels seems to have, that the “business as usual” scenario was indeed the upper curve, which now looks to markedly over-state warming.
Can anyone confirm which of the Hansen scenarios used a CO2 growth closest to the actual over the past 16 years?
Meanwhile, I’ll remain quietly skeptical.
Response: Scenario B has been closest to the actual growth rate, and as Hansen said in his testimony in 1988 it was the most probable scenario. -gavin
Having just finished the book, I find this characterization of it somewhat misleading.
Much of this commentary blurs the lines between the characters’ various opinions and statements in the text with Crichton’s overall point of view.
For example, Crichton uses individual weather station data in the context of a lawyer showing how the defense will try to pursuade a jury. The author of this piece suggests that the “good guy” says “there’s your global warming.” In fact, this “good guy” is a lawyer ignorant of the data. Crichton seems to wholeheartedly agree that “Only by amalgamating all of the records we have (after correcting for known problems, such as discussed below) can we have an idea what the regional, hemispheric or global means are doing. That is what is meant by global warming.”
The issue of Urban Heat is duscussed at length in the book, and one of Crichton’s main points is that the UHIE is a known issue that is factored into global warming estimates. One could read this article and get the false impression that Crichton failed to mention that UHIE is factored into estimates. Yet Crichton covers this extensively only to point out that such corrections could be challenged and we’re not dealing with raw data here.
This article suggests an error: “Greenland shows that, in the last hundred thousand years, there have been four abrupt climate change events.” In fact, this statement is made by the bozo actor character in the context of a speech that is grossly flawed. No reader could seriously infer that this is Crichton’s point of view, when the bozo character is humliated soon thereafter for his naive view of the constancy of climate and environment.
There are some good points brought out in this critique, but overall I didn’t find the book to be a slam on global warming science was much as it was a slam on exaggerations and overstatements based on that science.
From a complete layman who read the book: Is Crichton more correct, or is the IPCC more correct? Is man the cause of global warming?
Honestly, what I got of Crichton’s point of view is: We simply cannot predict the effects of global warming, or if it’s happening at all, or if we’re the cause. So we shouldn’t be making radical changes.
Seems to be plenty of scientists here, so I ask you all, what’s the real deal? In layman’s terms.
great article…..have you done a book review, or letter to an editor to any newspaper…..
In my previous critique of this critique, I left out a glaring point.
The “curious train of logic” Crichton uses in comparing global warming to eugenics is that both shared the same hallmarks of social movements supported by politicians, academics and celebrities, despite little hard science backing the claims of the movement.
The claim, “He argues, that since eugenics was studied in prestigious universities and supported by charitable foundations, and now, so is global warming, they must somehow be related.” is a gross mischaracterization of Crichton’s argument.
He specifically points out the following similarities between the eugenics movement and the global warming movement:
– Both won support of politicians and celebrities around the world.
– Both urge legislation that has little basis in hard science.
– Both shrug off harmful effects of urged changes, asserting vague benefits.
– In both cases open and frank discussion of the data and issues is supressed.
– Both won support of politicians and celebrities around the world.
– Both urge legislation that has little basis in hard science.
– Both shrug off harmful effects of urged changes, asserting vague benefits.
– In both cases open and frank discussion of the data and issues is supressed.
I haven’t read Crichton’s book, but if you’re accurately representing his statements, then every one of them is a blank assertion or logical fallacy.
1) The mere fact that a theory or methodology is widely accepted in its time–particularly among non-scientists–does not make it scientifically valid. The latter only comes from a firm foundation of empirical evidence. This cuts both ways, and that is both appropriate and expected in science. Regardless, the comparison is a non-sequitir, since eugenics fell out of favor not due to a lack of empirical evidence, but because it was recognized as poisonous to universal principles of human rights.
2) Eugenics had a firm basis in the genetic theory of inheritence. It wasn’t bad science, generally speaking. It was science put to an immoral purpose. As for the legislation that was urged by the “global warming movement” and has little basis in hard science…Care to give an example? Citation? Detailed refutation of the scientific evidence entered into the legislative record for a specific bill? Or are you just accepting Crichton’s assertions as fact?
3) I don’t even follow this one. Eugenics, by definition, advocates taking on certain costs–whether the economic price tag or the unpleasant moral implications of sterilizing hundreds of thousands of human beings–in the pursuit of racial purity, public health, reduced economic drag over the long term, etc. How does this have any parallel in the “global warming movement”–which, presumably, consists of scientists and informed laymen who agree that a preponderence of empirical evidence exists affirming the reality of anthropogenic climate change? What are the “harmful effects” of the supposed urged changes? What are the suupposed “vague benefits” being proffered?
4) I’ve never met a single scientist who wasn’t interested in critically examining evidence that contradicted his or her own data. Science requires an open forum for sharing of data and honing of theory. Care to point out an example of “suppression” of facts in climate change? Or even in eugenics, for that matter? Or perhaps C Crichton is just referring to science’s unwillingness to entertain anti-intellectual political whining from those whose lifestyles might be perturbed a touch by the reality that science has described?
BTW, what the heck is the “global warming movement”? Maybe I didn’t pay my dues, but no one told me about that particular movement. I guess the meet in the same shadowy corridors as the Bavarian Illuminati and the Priory of Sion?
“The mere fact that a theory or methodology is widely accepted in its timeâ??particularly among non-scientistsâ??does not make it scientifically valid.”
Which is precisely Crichton’s point.
“Regardless, the comparison is a non-sequitir.”
I don’t see how it is a non-sequitir. His claim is that eugenics resulted in immoral public policy, masquerading as policy based on hard science.
“Or are you just accepting Crichtonâ??s assertions as fact?”
I’m not accepting his assertions – just trying to accurately convey his arguments.
“What are the â??harmful effectsâ?? of the supposed urged changes?”
Crichton doesn’t go into this in his discussion on eugenics. But he clearly believes that environmental principles (he refers to “sustainable development” and the “precautionary principle”) have the effect of preserving the economic advantages of the West.
“Care to point out an example of â??suppressionâ?? of facts in climate change? ”
As evidence of his assertion, Crichton argues that “so many” of the vocal critics of global warming are retired professors who don’t have grant money on the line, and do not have a need to appease colleagues.
“BTW, what the heck is the â??global warming movement”?”
I’ll have to be more precise in my wording. He refers to the “eugenics movement”, but I don’t recall him referring to the “global warming movement.” Crichton invents many environmental groups (many of them are effectively PR agencies or legal funds) that are heavily involved in fund raising – particularly with the Hollywood crowd. These groups form the center of what I’m referring to as the “global warming movement” in Crichton’s book. But it seems he thinks these groups exert heavy influence on academics, politicians and the press, while effectively stifling dissenting opinion.
>This does not follow. Collective action is made up of the actions of individuals.
Three parts to this answer the first is the obvious one that I assume you understand already Secondly a idea slightly harder to grasp but simple economics and third is related to what we are proposing as a solution
1) The problem is that whether or not everyone reduces CO2 output you can be 100% sure YOUR CO2 output wont make a significant difference thus it is not surprising if some people can’t get the enthusiasm to do it. (of course that is why we have governments to force people to take collective interests into consideration but as you will see later even this is not sufficient).
2)not only do you make only the slightest difference to the total but your non use drives the price down making it easier for others to use more as well as making no change at all to the fundimental economics of burning oil, therfore your reduction in usage increases other peoples usage – not just in your own country but in the world.
The only way to solve the problem is on the supply side – safely dispose of the oil OR prevent it from being removed from the ground (by buying it there or via force).
> “if some huge quantity of people don’t do anything about global warming then we’re screwed, and noone else seems to be doing anything so I won’t either”.
That argument is valid in a sense but it is even worse than that – even a small quantity of people don’t do anything about it – you are still screwed. And EVEN WORSE
3) EVEN IF everyone does somthing about it and slows consumption by some arbitrary percentage you only delay the inevitable. (if you change the date by which all the economically feasible oil is burnt from 2100 to 2110, who alive in 2110 will care?)
One also has an additional problem that global warming is likely to be good for a not insignificant number of people.
In my comment #31, I wrote, “Michael Crichton’s guess of ~0.8 degrees Celsius for the 21st century is far, far better than the IPCC projections of 1.5 to 5.8 degrees Celsius (from 1990 to 2100).”
Dr. Schmidt responded: “So your point is that working on no information (i.e. Crichton), is better than working with the limited information that we have?”
No, that is not my point. My point is that the information we have supports Michael Crichton’s guess, and does *not* support the IPCC projections.
For example, according to the IPCC, there is approximately a 50/50 chance that atmospheric methane concentrations will rise to approximately 2500 ppb by 2060, from a value of approximately 1750 ppb in 2000. That’s an average increase of 12.5 ppb per year. But recent increases in methane concentrations have not been remotely close to 12.5 ppb per year. They’ve been more like less than 3 ppb per year. What justification is there for the IPCC projecting that methane will increase by an average of 12.5 ppb per year for the next 60 years?
Similarly, according to the IPCC, there is approximately a 50/50 chance that atmospheric CO2 concentrations will rise to approximately 560 ppm by 2060, from a value of approximately 370 ppm in 2000. That is an average increase of approximately 3.2 ppm per year. But over the last 20 years, the average increase has been more like 1.5 ppm per year. What justification is there for the IPCC projecting that CO2 concentrations will increase by an average of 3.2 ppm per year for the next 60 years?
Dr. Schmidt concludes, “But arguing that because we don’t know everything, we might as well pull a number out of thin air is a little odd.”
Such an argument would indeed be odd. (It would be as odd as an “argument from authority” that the IPCC’s projections should be accepted, simply because they are the “consensus” of the IPCC!) But that is *not* my argument.
My argument is that available evidence supports Michael Crichton’s guess of ~0.8 degrees Celsius, and available evidence overwhelmingly does *not* support the IPCC’s projections of 1.5 to 5.8 degrees Celsius (with a mean of 3.6 degrees Celsius).
Response: IPCC did not attach any probabilities to any of the scenarios (which I think was probably a mistake, as Steve Schneider has also argued). However, it is not inconceivable that the current rate of growth of 1.4%/yr in fossil-fuel related emissions could reach 2%/yr or more due to rapid economic growth in the developed world. Growth rates averaged 4.7%/year between 1945 and 1973 for instance. It would be negligent not to include scenarios that are in some sense a worst case as long as other scenarios with different assumptions were also explored. We regularly use scenarions that are different from the standard IPCC ones for precisely this reason. However even the moderate scenarios which have eventual stabilisation give more warming than 0.8C. Even in the extremely unlikely event that there is no further growth in emissions, the current planetary energy imbalance (estimated to be almost 1W/m2) (due to the ocean thermal inertia) implies that there is around 0.5 C extra warming already in the pipeline that will be realised over the next 20 to 30 years. Any growth of emissions above that will lead to more warming. Thus the probability of a warming as low as 0.8C over the next 100 years is extremely low. – gavin
While I thought the book was poorly written, I actually appreciate what I took to be it’s central message.
It is clear that we, collectively, still do not know what is happening to the world’s climate at the moment. Unfortunately, that does not stop journalists, environmentalists, politicians, and even scientists from speculating and pressing for us all to “do something”. The fact that the impact of these “somethings” is even less understood than the problem doesn’t seem to cause anyone any concern.
Personally, I believe in a century we will look back on the global warming crisis as a low point in the history of our society. It seems to be impossible to express an opinion on the issue without attempting also taking a shot at any dissenters. It’s quite common to hear people justify their belief in global warming as “Well, a whole bunch of people say it’s true”.
The fact that so many people in the world believe, without understanding even the basic concepts, that global warming is indeed an issue should be a point of concern, not cause for celebration.
Once again, Michael Crichton exaggerates and in fact reverses the evil. In Disclosure, he pretended that the danger of a woman sexually harrassing a man (which occurs very rarely in real life) was far far far worse than that of a man sexually harrassing a woman (which happens far too often). Now he blames ecologists for terrorism. Didn’t Tom Clancy already do that in Rainbow Six? Just like Crichton ripped off Connie Willis’s Doomsday Book for his Timeline.
I am interested in understanding the accuracy of the IPCC model. There are graphs showing the model
predicting observed climate changes, but these are not enough to give an observer any confidence unless
answers to the following points are given:
a) Are components (eg the ocean model) developed separately and used unchanged, or re-parameterised?
b) Are parameters adjusted by comparing predicted and observed values? How exactly?
c) How much of the existing data has been used to fit the model parameters?
d) How many model parameters (tweakable, not fixed by the underlying physics) are there?
e) Are those scientists who evaluate the model aware of which data has been used in fitting?
f) Has any attempt at cross-validation or other regularisation of the model been made?
If these questions have not been considered then the model has been poorly evaluated and may be worthless.
Answering these questions will also allow the accuracy of the predictions to be estimated.
Have these questions been answered?
Response: Modelling groups spend pretty much all their time trying to answer these kinds of questions. A summary of results can be seen in the IPCC reports of course. However, we intend to expand upon this in future posts. Watch this space! – gavin
[Response: you say *the* IPCC model. This is wrong. Thre are several, not just one. Different groups would answer the various questions you have above differently. For example, HadCM3 was built to produce a stable control climate resembling the average of, say, the last 30 years. It wasn’t tuned to fit the temperature change over the last century or so – William]
Bruce, simple question for you and other skeptics. Given these three alternatives,
(a) Everyone goes to university and studies climate science until they are capable of assessing the evidence themselves
(b) Most people use the heuristic that “a lot of people” (i.e. a lot of climate scientists) believe that anthropogenic climate change is real, and go with that
(c) We ignore all the climate scientists and believe noted founts of wisdom like Michael Chrichton, Rush Limbaugh, and George W. Bush (no wait, even he now agrees that global warming is real – as do the CEOs of two big oil companies – so you’re more extremist than Bush, if you don’t)
…which alternative do you think we should go for? Or do you have a better alternative?
Second in terms of the effects of political measures. All sorts of political policies have effects that are difficult to measure precisely. However, you can make broad-brush claims. A massive global move towards sustainable energy sources is likely to hurt the oil companies, but not the US economy as a whole, for example.
Also, what many environmentalists argue is that we have to look more at quality of life measures than at GDP. Oil spills may increase GDP, but not many people would argue that oil spills are a good thing. Therefore, GDP is not a perfect measure of what economic policy should aim towards. Plausibly, we can improve on GDP as a measure of “well-being”, by augmenting it with things other than money. Which makes sense, because pretty much nobody accross the entire political spectrum thinks that money is the only thing that matters in life.
Let me begin with a caveat-the unsubtle distinction between my views on climate change and those of a certain other Seitz are set forth in the summer 1990 issue of The National Interest.
Mike Crichton’s latest pageturner has drawn on my earlier critique of the epic overselling of “Nuclear Winter” , but fails to mention how I categorized the media hype in dialog with Steve Schneider at a 1987 symposium:” Nuclear Winter is a joke played at the expense of the credibility of the climate modeling community on the eve of the global warming debate”
Plus de ca change, two decades later we have ‘The Day After Tomorrow’ with its title extending that of the seminal Freeze Movement TV extravaganza of the Reagan years slugging it out with Mike’s latest opus. As paradigms of how to educate the public, they differ no more in quality than Godzilla and Mothra.
The raillery both film and book evoke from the politically offended, or the ideologically scandalized ought to be cause for introspection. At least Mike represents an intelligent Republican _trying- to think about science, and I believe a bipartisan duty exists to acknowledge that science politicized is science betrayed.
Dick Lindzen will be amused to know that Crichton’s sense of humor is still in gear- the MIT protagonist Kenner is the namesake of the conservative Yale professor tasked with teaching several generations of Bush’s English, but more generally famed as the author of ‘A Rhetoric Of Motives’ .
Perhaps some public spirited NSC type will incorporate that excellent book into some morning’s PDB.
It never makes sense to me, those who attach evil agenda to environmentalism. What is the supposed motivation behind “eco-terrorism”?
Let me pose a simple question, and follow it up: if Michael Crichton had written a book which supported mainstream climate science on global warming, would he potentially sell as many copies as he will with “State of Fear,” a book which tells the story of a global warming conspiracy? Or putting it another way, “Which will sell more copies: Crichton’s ‘State of Fear’ or the IPCC’s ‘WG1 Report?'”
Couldn’t we who prefer the scientific mainstream convince authors equal to Michael Crichton to write novels?