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Global Warming debate Küresel Isınma Müzakeresi

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Along with Richard Somerville (UC San Diego) and Brenda Ekwurzel (Union of Concerned Scientists), I’ll be appearing at a debate on Wednesday (March 14th) about whether Global Warming is a crisis (or not). That might have gone without notice (like most of my public talks), except that our opponents are Michael Crichton, Richard Lindzen and Philip Stott. The preliminary position statements (from me and from Philip Stott) are available on the ABCnews site. It’s sold out, but the proceedings will be broadcast on NPR (for instance, WNYC 820 AM on Friday, March 23, 2007 at 2PM) and there will be a podcast (though I don’t know if it will stream live). There’s an online poll as well for what that’s worth.

I’m quite looking forward to this, but I have to admit to conflicting thoughts. Does participating help perpetuate the idea that global warming per se is still up for debate? Is this kind of rhetorical jousting useful for clarifying issues of science that most people there will only superficially grasp? Can this be entertaining and educational? Or does it just validate the least serious opposition? Is it simply a waste of time that would be better spent blogging? ;)

I’d be interested in any thoughts people might have.


Küresel Isınma Müzakeresi

Ingilizce’den çeviren Figen Mekik

Richard Sommerville (UC San Diego) ve Brenda Ekwurzel eşliğinde (Union of Concerned Scientists-Endişeli Bilim Insanları Birliği), 14 Mart Çarşamba günü küresel ısınmanın kriz olup olmadığını tartışacağımız bir müzakereye katılacağım. Bu pek farkına varılmadan geçip gidebilirdi (benim pek çok halka açık konuşmam gibi) ama bu sefer karşı tarafta Michael Crichton, Richard Lindzen ve Phillip Stott var. Iki tarafın da tezini savunan ayrı birer yazı (ben ve Stott yazdık) ABC news sitesinde var. Müzakere’ye biletler çoktan satılmış, bitmiş. Ama müzakere hem radyoda (NPR, mesela WNYC de Cuma-23 Mart- sabahı 8:20de) yayınlanacak hem de bir podcast hazırlanıyor (ama canlı olmayacak sanırım). Internet sitelerinde bir de anket var.

Ben buna pek hevesliyim, ama bazı çelişkili düşüncelerim de var. Böyle bir müzakereye katılmak, küresel ısınmanın olup olmadığının hala tartışmaya açık olduğunu savunmak mı oluyor? Bu tip çekişmeler, oradaki insanları bilimsel konularda eğitmeye yarar mı? Bu hem eğlenceli hem de eğitici olabilir mi? Ya da ciddi bir muhalefeti geçerli kılmaya mı yarıyor? Yoksa bloglarla uğraşmaya ayıracağım zamanı buraya giderek boşa mı harcamış olacağım? ;)

Tüm fikirlerinize açığım.

Swindled: Carl Wunsch responds Aldatıldık: Carl Wunsch Cevap Veriyor

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The following letter from Carl Wunsch is intended to clarify his views on global warming in general, and the The Great Global Warming Swindle which misrepresented them.

Partial Response to the London Channel 4 Film “The Global Warming Swindle”

Carl Wunsch 11 March 2007

I believe that climate change is real, a major threat, and almost surely has a major human-induced component. But I have tried to stay out of the `climate wars’ because all nuance tends to be lost, and the distinction between what we know firmly, as scientists, and what we suspect is happening, is so difficult to maintain in the presence of rhetorical excess. In the long run, our credibility as scientists rests on being very careful of, and protective of, our authority and expertise.
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Swindled! Aldatıldık!

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By William and Gavin

On Thursday March 8th, the UK TV Channel 4 aired a programme titled “The Great Global Warming Swindle”. We were hoping for important revelations and final proof that we have all been hornswoggled by the climate Illuminati, but it just repeated the usual specious claims we hear all the time. We feel swindled. Indeed we are not the only ones: Carl Wunsch (who was a surprise addition to the cast) was apparently misled into thinking this was going to be a balanced look at the issues (the producers have a history of doing this), but who found himself put into a very different context indeed [Update: a full letter from Wunsch appears as comment 109 on this post]

So what did they have to say for themselves?
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‘Cosmoclimatology’ – tired old arguments in new clothes ‘Cosmoclimatologia’ – argumentos velhos e ultrapassados em nova roupagem

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Image from cosmosIn a recent issue of the journal Astronomy and Geophysics (A&G), Henrik Svensmark coined a new term: ‘cosmoclimatology’ . I think ‘cosmoclimatology’ is a good and refreshing name for anything combining our cosmos with our climate. However, all other aspects of the article I found very disappointing. We have already covered most of these topics before, but the A&G articles provides us with some new aspects to discuss. Furthermore, Svensmark is the Director for Center for Sun-Climate Research, Danish National Space Center, and therefore influential. He is also the co-author of a recent book with Nigel Calder that received some attention. Furthermore, a laboratory experiment of his also managed to make some headlines. It seems that solar forcing is one of the sceptics’ last trenches in the debate about climate change. In my view the A&G paper therefore merits a comment as long as the same old and worn arguments resurface without discussing misgivings from the critics.

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Hurricane Heat Kasırga AteşiChaleur d’ouragan

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The big problem with much of the discussions about trends in hurricane activity is that the databases that everyone is working from are known to have significant inhomogeneities due to changes in observing practice and technology over the years. So it’s not surprising that a new re-analysis (Kossin et al, published yesterday) has been generating significant interest and controversy among the hurricane research community (see e.g. Prometheus or Chris Mooney). However, rather than this study being taken for what it is – a preliminary and useful attempt to make homogeneous a part of the data (1983 to 2005) – it is unfortunately being treated as if it was the definitive last word. We’ve often made the point that single papers are not generally the breakthroughs that are sometimes implied in press releases or commentary sites and this case is a good example of that.
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Round up and thanks

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A few tidbits from around that may be of interest:

  • Tom Yulsman is running a new blog (now linked in our blogroll) for the Center for Environmental Journalism at U. Colorado, Boulder, covering climate change as one of his ‘beats’.
  • The Global Roundtable on Climate Change (GROCC), made up of business leaders, NGOs and academics released a statement on climate change. (Coverage BBC, Reuters)
  • The UN Foundation (an independent NGO established to support the UN mission) has helped put together a site called ‘IPCC facts‘ to help with the outreach associated with the IPCC Fourth Assessment. We haven’t examined every page, so if there are any questions, this is as good a place as any to go over them.

On the lighter side, those people who are fond of the offsetting concept (usually applied to carbon emissions) may find this site interesting (hat tip to Yarrow).

Finally, the more multi-lingual of our readers may have noticed the proliferation of translations of RC posts in recent weeks. We now have regular contributors translating articles into French, Slovak, Swedish and Portugeuse (as denoted by the hybrid flags associated with relevant articles). We can offer them nothing more than our deep gratitude – recent contributions have been from: Valérie Masson-Delmotte, Fernando Manuel Ramos and Ivan Bergier Tavares de Lima (ClimaGaia), Alexander Ač, Olivier Daniélo, Etienne Pesnelle, Jacob Wallström and Yves Fouquart. Many thanks to all!

(And if anyone else would like to help out on an occasional basis translating posts to their native language, please let us know. )

Update: And now turkish! (thanks to Figen Mekik).

Climate Reporting in Physics World Reportagem sobre o Clima na Physics World

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PhysicsWorld cover, Volume 20, no. 2, February 2007 The February 2007 issue of PhysicsWorld contains several articles relevant to climate research, with a main feature article on climate modelling written by Adam Scaife, Chris Folland, and John Mitchell, and a profile on Richard Lindzen as well as an article on geoengineering in the ‘News & Analyses’ section. The magazine also contains an article (‘Living in the greenhouse’) under ‘Lateral Thoughts’ that brings up a bunch of tentative analogies to a wide range of topics completely unrelated to the greenhouse effect in a technical sense, and an editorial comment ‘Hot topic‘, arguing that it would be wrong of PhysicsWorld to ignore those outside the mainstream. To be more precise, the editorial comment devotes a few lines justifying the profile on Lindzen and the report on geoengineering, with a reference to a Feynman quote: “There is no harm in doubt and scepticism, for it is through these that new discoveries are made”. Wise words! Nevertheless, I cannot resist making some reflections.

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Aerosols: The Last Frontier? Aerossóis: A Última Fronteira?

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Guest commentary from Juliane Fry, UC Berkeley

The recently released IPCC 2007 Fourth Assessment Report Summary for Policymakers reminds us that aerosols remain the least understood component of the climate system. Aerosols are solid or liquid particles suspended in the atmosphere, consisting of (in rough order of abundance): sea salt, mineral dust, inorganic salts such as ammonium sulfate (which has natural as well as anthropogenic sources from e.g. coal burning), and carbonaceous aerosol such as soot, plant emissions, and incompletely combusted fossil fuel. As should be apparent from this list, there are many natural sources of aerosol, but changes have been observed in particular, in the atmospheric loading of carbonaceous aerosol and sulphates, which originate in part from fossil fuel burning. While a relatively minor part of the overall aerosol mass, changes in the anthropogenic portion of aerosols since 1750 have resulted in a globally averaged net radiative forcing of roughly -1.2 W/m2, in comparison to the overall average CO2 forcing of +1.66 W/m2.
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Save the World! Earn $25 million! Dünya’yı Kurtar! 25 Milyon Dolar Kazan!Sauvez la planète ! Gagnez 25 millions de dollars !

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Guest commentary from Juliane Fry, UC Berkeley

On February 9, The Virgin Group chairman Sir Richard Branson announced a $25 million prize for anyone who can demonstrate “a commercially viable design which results in the removal of anthropogenic, atmospheric greenhouse gases so as to contribute materially to the stability of Earth’s climate.” At the press conference announcing this “Virgin Earth Challenge”, Branson was joined by Al Gore, and the panel of judges for the competition includes additional climate change celebrities: James Hansen, James Lovelock, Tim Flannery, and Sir Crispin Tickell.

The goal of the competition is to find a method that will remove at least 1 billion tons of carbon per year from the atmosphere. It will be very interesting to see what ideas come to the fore to scrub CO2 from the atmosphere. $25m should encourage some creativity! (and of course, once working should bring in a significant amount of carbon offset money). A ruckus was caused last year when discussion of injecting SO2 into the stratosphere to form reflective sulfate aerosols to mask global warming made scientists feel they needed to state their position on this controversial, poorly understood proposal. During the discussion, a New York Times feature (described here ) discussed various “geo-engineering” alternatives to exert a cooling effect to mask global warming. At least in this case, we are not seeking to add something new and uncertain to the atmosphere, but rather, remove something that we added.

Comentário convidado de Juliane Fry, UC Berkeley (tradução de F. M. Ramos e I. B. T. Lima)

No dia 9 de fevereiro, o presidente do Grupo Virgin, Sir Richard Branson, anunciou um prêmio de US$ 25 milhões para quem demonstrar “a viabilidade comercial de algum projeto para retirada da atmosfera de gases de efeito estufa de origem antropogênica, para contribuir materialmente para a estabilidade do clima da Terra”. Na coletiva de imprensa que lançou o desafio, batizado de “Virgin Earth Challenge“, Branson estava acompanhado de Al Gore, e o corpo de jurados da competição incluía outras celebridades das mudanças climáticas como James Hansen, James Lovelock, Tim Flannery, e Sir Crispin Tickell.

O objetivo da competição é encontrar um método que seja capaz de remover pelo menos 1 bilhão de toneladas de carbono por ano da atmosfera. Será muito interessante observar que idéias surgirão para varrer CO2 da atmosfera. US$ 25M devem suscitar alguma criatividade! (e naturalmente, uma vez implementado, proporcionar muito dinheiro na forma créditos de compensação de carbono). No ano passado, o barulho causado pela proposta de injeção de SO2 na estratosfera para formar uma camada refletiva de aerossóis de sulfato, de modo a neutralizar o aquecimento global, forçou muitos cientistas a tomar uma posição clara a respeito desta proposta controvertida e pouco compreendida. Durante os debates, uma matéria do New York Times (descrita aqui) discutiu várias alternativas de “geo-engenharia” para criar um mecanismo de resfriamento de mascarasse o aquecimento global. Pelo menos neste caso, não estamos procurando adicionar algo novo e incerto na atmosfera, mas ao contrário, retirar algo que foi adicionado.



Misafir yazar Juliane Fry, California Üniversitesi, Berkeley (Ingilizce’den çeviren: Figen Mekik)

9 Şubat gunu, The Virgin Group’un (Bakir Grup) başkanı, Sir Richard Branson 25 milyon dolar ödüllü bir yarışma açıklamasında bulundu. Yarışmanın amacı dünya’nın küresel iklimini dengeleyebilecek yeni bir tasarım üretmek. Insanlar tarafından atmosferdeki yoğunluğu artırılan sera gazlarını eksiltebilen ve bunu en ucuz şekliyle başarabilen tasarımcıya 25 milyon dolar ödül verilecek. Bu Bakir Dünya Yarışmasının açıklandığı basın toplantısına, Branson’a Al Gore eşlik ettiği gibi, yarışmada hakemlik yapacak panelde yer alan diğer iklim meşhurları da katıldılar: James Hansen, James Lovelock, Tim Flannery ve Sir Crispin Tickell.

Yarışmanın amacı yılda en az 1 milyar ton karbonu atmosferden çekebilen bir yöntem geliştirmek. Atmosferdeki fazla karbon dioksidi yok etmek için ne çeşit fikirlerin ortaya atılacağını görmek çok ilginç olacak. Eh, 25 milyon dolar biraz yaratıcılığı teşvik eder herhalde (ve tabii ki, bu yeni yöntemler uygulandığında kâr da artar). Geçen sene küresel ısınmayı maskelemek amacıyla stratosfere SO2 aktarılarak yaratılacak parlak sülfat taneciklerinin (aerosol) iklimi soğutma etkisi tartışıldığında bir hayli gürültü koptu. Bilimciler çok tartışmaya sebep olan ve pek iyi anlaşılamayan bu konu hakkındaki tutumlarını açıkça beyan etmek istediler. Bu tartışma dahilinde New York Times’da çıkan bir yazı (tarifi burada) küresel ısınmanın etkilerini azaltmayı amaçlayan başka jeo-teknik çözümler önerdi. En azından bu sefer, bu 25 milyon dolarlık yarışmayla atmosfere yeni ve etkisi henüz tam kestirilemeyen bir şey eklemeyen bir çözüm aranıyor.


Juliane Fry, UC Berkeley, Traduit par Etienne Pesnelle

Le 9 février dernier, Richard Branson, président du groupe Virgin, a annoncé qu’il offrait 25 millions de dollars à quiconque pourra présenter « une invention commercialement viable qui permette de retirer de l’atmosphère les gaz à effet de serre d’origine anthropique, de façon à contribuer sensiblement à la stabilisation du climat de la Terre ». A la conférence de presse où il annonçait son « « Défi Virgin pour la Terre » », Branson a été rejoint par Al Gore, et le comité des juges de ce concours comprend d’autres célébrités du réchauffement climatique : James Hansen, James Lovelock, Tim Flannery, et Sir Crispin Tickell.

L’objectif du concours est de trouver une méthode qui pourra retirer de l’atmosphère au moins un milliard de tonnes de carbone par an. Il va être très intéressant de voir quelles idées de nettoyage de l’atmosphère vont émerger. 25 millions de dollars devraient encourager la créativité ! (et bien sûr, quand ça fonctionnera, ça devrait rapporter une somme significative en crédits de compensations d’émissions de carbone). Il y eut du grabuge l’année dernière, quand le débat à propos de l’injection de SO2 dans la stratosphère, visant à produire des sulfates en aérosol réfléchissant la lumière solaire qui contreraient le réchauffement climatique, a donné l’impression aux scientifiques qu’ils avaient besoin d’exposer leur position sur cette proposition mal comprise et controversée.

Durant ce débat, un article de fond du *New York Times* (décrit ici) a commenté les différentes options de « géo-ingénierie » ayant un effet refroidisseur contrant le réchauffement climatique. Au moins cette fois-ci, on ne cherche pas à ajouter quelque chose de nouveau et d’incertain à l’atmosphère, mais bien à en retirer ce qu’on y a ajouté.

What triggers ice ages? O que Dispara as Eras Glaciais? Buzul Çağlarını Tetikleyen Nedir?Qu’est ce qui déclenche les glaciations?

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by Rasmus Benestad, with contributions from Caspar & Eric

In a recent article in Climatic Change, D.G. Martinson and W.C. Pitman III discuss a new hypothesis explaining how the climate could change abruptly between ice ages and inter-glacial (warm) periods. They argue that the changes in Earth’s orbit around the Sun in isolation is not sufficient to explain the estimated high rate of change, and that there must be an amplifying feedback process kicking in. The necessity for a feedback is not new, as the Swedish Nobel Prize winner (Chemistry), Svante Arrhenius, suggested already in 1896 that CO2 could act as an amplification mechanism. In addition, there is the albedo feedback, where the amount of solar radiation that is reflected back into space, scales with the area of the ice- and snow-cover. And are clouds as well as other aspects playing a role.

por Rasmus Benestad, com contribuições de Caspar & Eric

Em um artigo recente da Climatic Change, D.G. Martinson e W.C. Pitman III discutem uma nova hipótese que explica como o clima pode mudar abruptamente entre eras glaciais e períodos interglaciais (quentes). Eles argumentam que as mudanças na órbita da Terra ao redor do Sol em isolado não são suficientes para explicar as altas taxas de mudanças estimadas, e que deve necessariamente haver a ação de um mecanismo de feedback (ou retro-alimentação) amplificando o processo. A necessidade de um feedback não é nova, pois o sueco ganhador do Prêmio Nobel (Química), Svante Arrhenius, já havia sugerido em 1896 que o CO2 deveria agir como um mecanismo de amplificação. Além do mais, existe o feedback do albedo, pelo qual a quantidade de radiação solar que é refletida de volta ao espaço é escalonável com a área de cobertura de gelo e neve. E existem nuvens bem como outros aspectos envolvidos.

Orbital forcing A hipótese de Martinson & Pitman III formula que a entrada de água doce funciona em consonância com o ciclo de Milankovitch e o feedback de albedo. Eles concluem que os ‘maiores’ términos podem somente acontecer após um acúmulo de gelo grande o suficiente para isolar o Artico, inibindo o fluxo de entrada de água doce até um ponto em que o aumento da salinidade na camada superficial, através de um vagaroso e contínuo crescimento do gelo marinho, causa uma inversão das águas marinhas do Ártico (pelo efeito na circulação atmosférica e nas correntes oceânicas). A inversão vertical traz água quente de baixo para cima, promovendo condições mais favoráveis ao degelo. A salinidade também tem um papel, mas a hipótese não menciona variações de gases de efeito estufa (GEE). Algumas questões: Martinson e Pitman III esqueceram disso? Ou os GEE representam somente uma pequena contribuição? E, não poderiam as mudanças nos GEE explicar boa parte da variabilidade? Por outro lado, parece plausível que mudanças na salinidade e na entrada de água doce poderiam afetar a formação de gelo marinho e a convecção profunda. Contudo, até o presente, a hipótese proposta por Martinson and Pitman III é meramente uma especulação, e estamos aguardando para ver se a hipótese pode ser testada através de experimentos de modelos numéricos (o que pode requerer modelos oceânicos e de gelo marinho com maior resolução que os atualmente usados em modelos climáticos globais). Seria interessante conduzir experimentos para avaliar a significância individual da água doce, dos GEE e o efeito combinado.

Uma reação ao trabalho de Martison e Pittman é: Onde está o cálculo de energia? Gases de efeito estufa contribuem somente com alguns W/m2, em contraste com uma forçante >40 do ciclo sazonal de Milankovich. Para esta nova idéia ter mérito, teria sido melhor ter no mínimo fluxos de calor em paralelo com a forçante radioativa do CO2. Estudos de modelagem anteriores encontraram que GEE produzem aproximadamente 50% de todo Último Máximo Glacial (inglês, LGM) para a resposta da temperatura atual (veja por exemplo Broccoli & Manabe), a outra parte sendo o albedo, etc., que respondem ao ciclo sazonal de irradiância. É muito difícil isolar completamente as causas individuais pois as mudanças nos GEE podem produzir alterações na distribuição de nuvens e gelo marinho. Mas a grosso modo, se você rodar um LGM e somente somente reduzir o nível do mar, introduzir as calotas de gelo, mudar a vegetação, adicionar alguma poeria (embora esta ainda seja grosseira), então você alcançaria ao redor de 50% do caminho que você quer ir. Mude a concentração de GEE e você chegaria mais próximo. Isso é mais ou menos o que Manabe e Stouffer mostraram há quinze anos atrás. A questão é se realmente precisamos de algo mais, e se esse ‘algo mais’ tem força suficiente.

traduzido por Ivan B. T. Lima e Fernando M. Ramos.


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