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German Climatologist on Criticism of IPCC: 'We Received a Kick in the Pants'

German physicist Hans Joachim Schellnhuber is one of Angela Merkel's advisers on climate change. In an interview with SPIEGEL, he discusses extreme weather events, global warming's winners and losers, and the effects of the crisis of confidence in climate research.

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SPIEGEL: Mr. Schellnhuber, Russia is burning and floods have inundated Pakistan. Are such extreme weather phenomena increasing because of gradual climate change?

Hans Joachim Schellnhuber: Such events certainly do correspond to what we expect from a warmer world. We have seen record average global temperatures for more than a year now, and that increases the likelihood of regional heat waves like the one in western Russia at the moment. Besides, our climate models show that the South Asian monsoon is becoming more temperamental as a result of anthropogenic changes to the environment.

SPIEGEL: There have also been forest fires and floods in the past. Isn't it too easy to automatically link natural disasters to climate change?

Schellnhuber: Of course it would be wrong, from a scientific perspective, to establish this relationship indiscriminately. But it would be just as unscientific to stop searching for such relationships, merely because the public's interest in climate change has temporarily diminished.

SPIEGEL: In Russia, in particular, fire prevention has failed. The forest service was abolished, and fire departments in many places are in terrible condition. Do these major fires show that extreme weather situations don't necessarily lead to catastrophes, but that poor crisis management is really to blame?

Schellnhuber: That's undoubtedly correct. In most cases, it's social mismanagement that creates the conditions for social catastrophes. Often one can get away with having inadequate precautionary measures, provided the weather plays along. But extreme weather relentlessly exposes human mistakes and our crimes against nature. The German state of Brandenburg (editor's note: where the Potsdam Institute for Climate Impact Research is based) offers an example of the right way to do things. Even though there are more forest fires here than in the past, due to global warming, the surface area burned by the fires has decreased substantially, thanks to improved monitoring with smoke detectors.

SPIEGEL: As climate adviser to the chancellor, you have a particularly high profile. Because of your frequently ominous predictions, critics have dubbed you the "Cassandra of Potsdam," after the figure in Greek mythology whose predictions always went unheard. Why do you always have to scare people?

Schellnhuber: Let me answer your provocative question in an objective way. As an expert, it's possible that I tend to point to dangers and risks more than to opportunities and possibilities -- similarly to an engineer who builds a bridge and has to make people aware of everything that could cause it to collapse. Warning against a possible accident is in fact intended to reduce the likelihood of an accident. And a sudden shift in the climate could have truly catastrophic consequences. Besides, in Greek mythology Cassandra was always right -- unfortunately.

SPIEGEL: Does that justify constantly predicting the end of the world?

Schellnhuber: Naturally, we have to be careful not to dramatize things. After all, scientific credibility is our unique selling point. But I do confess that when you have the feeling that people just aren't listening, it becomes very tempting to turn up the volume. Naturally, we have to resist this temptation. On the other hand, the media often portray my statements in one-sided ways…

SPIEGEL: Can you give us an example?

Schellnhuber: Take agriculture, for example. If temperatures rise, harvests will suffer, in cereal crops, for example. But at the same time the higher level of CO2 in the atmosphere will lead to improved fertilization of plants. This fertilization from the air will make up for a large portion of the heat damage, perhaps even overcompensating for it. In other words, we could even get higher yields for a certain amount of time, provided there is enough water. In talks I give on the subject, I always mention both effects: the heat damage and the CO2 fertilization. But such subtleties are lost when it comes to how the issue is perceived by the general public.

SPIEGEL: It wasn't just misunderstandings that shook public confidence in climate research in recent months. A number of statements in a report by the Intergovernmental Panel on Climate Change (IPCC), such as one on the supposedly rapid melting of the Himalayan glaciers, turned out to be appalling errors.

Schellnhuber: There were only a few slip-ups, but they were extremely vexing. The IPCC is in the public eye, and there is so much at stake that we cannot allow mistakes of this magnitude to be made. The IPCC now needs to do its homework to overcome the credibility crisis that's occurred. We received a kick in the pants that probably did us a lot of good.

SPIEGEL: A scientific investigation panel in the Dutch parliament accuses the IPCC of overemphasizing the negative consequences of climate change.

Schellnhuber: On balance, this accusation is unjustified. It's not like the IPCC is hiding its true face, which is characterized by ugly exaggerations, behind a mask. For example, the IPCC has deliberately made cautious and restrained predictions regarding the rise in sea levels. The IPCC is set up in such a way that it smoothes things out as much as possible and uses conservative wording, so that all scientists involved can ultimately support the report.

SPIEGEL: Anyone who soberly asks for a cost-benefit analysis of climate change is demonized as a heretic. Why is it such a taboo to talk about the advantages of global warming?

Schellnhuber: You're right -- we do have to highlight the opportunities and benefits for some regions of the world more than we have done so far. There will certainly be winners, at least temporarily, especially in the northern latitudes. At a conference in Moscow, Russian Prime Minister Vladimir Putin told me quite openly: We are looking forward to global warming. We won't need to heat as much, our fleet will be able to operate in an ice-free sea, and we'll have more fertile land to farm. But is this really true? The current forest and peat fires show that global warming could also have drawbacks for Russia. The problem is that the consequences of climate change, both good and bad, have not been adequately studied yet. More than 90 percent of funding is still being used to investigate scientifically if humans are responsible for climate change. But this question has already been answered a long time ago: They are.

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1. Is CO2 the only cause of warming?
billryan 08/18/2010
A climatologist writes at length about the problems of global warming, but the only solution presented is a system of taxing industry and rebuilding the world industry. Not one word about the recent activity of the sun, we have had a very unusual condition. The lack of sunspots in 2008, made it a century-level year in terms of solar quiet. Remarkably, sunspot counts for 2009 have dropped even lower. As of March 31st, there were no sunspots on 78 of the year's 90 days to date (87%). The lack of solar activity and the resulting changes in the upper levels of our atmosphere may be a cause of the solar warming. No political actions punishing the evil industries will have any effect on solar warming.
2. What really matters is the scientific method
GeraldoLino 08/18/2010
The kernel of all this stuff is related to a simple application of the scientific method to the anthropogenic warming hypothesis. The hypothesis is that Mankind is affecting the climate dynamics with its carbon emissions released since the 18th century Industrial Revolution. In order to corroborate it there would have to be at least some perceivable and conspicuous changes in the evolution of certain climate parameters like temperatures, or climate-influenced factors like the sea level, as compared to their behaviour before the Industrial Revolution, in such a way that the human interference could be clearly identified. Such conspicuous index of change would be the long sought after “smoking gun” of the anthropogenic hypothesis. On to the facts: according to the 2007 IPCC report (AR4), the average atmospheric temperature has increased 0.8 degree centigrade, and the sea level has raised 0.2 m since 1870. Well, it happens that during the Holocene, the 12,000 years-old geological epoch in which our Civilization has existed, there have been several periods hotter than the current one and sea levels also higher than the current ones. For example, during the Middle Holocene, some 5,000-6,000 years ago, the sea levels were 3 to 4 meters higher than the current ones, while the average temperatures were at least 2 degrees centigrade higher, as indicated by hundreds of researches carried out in dozens of countries and in all continents. Also, the temperature rise since 1870 means a rising rate of 0.06 degree centigrade per decade, one order of magnitude lower than the warming transition to the Holocene 12,000 years ago, when the temperatures raised 6-8 degrees centigrade in less than a century. Well, dung and firewood were the only fuels used by Mankind during the Middle Holocene. If there were higher temperatures and sea levels then, and if the global warming was much faster 12,000 years ago, hence it is simply not possible to distinguish the little variations occurred since the late 19th century from the much wider natural oscillations that happened before. The only conclusion arising from these facts is that the anthropogenic hypothesis has no basis in the real world evidences, remaining a mere fabrication from mathematical models. As a corollary, any proposal of changing the entire energy structure of the world economy, which is 80% dependent from fossil fuels, can only be regarded as preposterous (or motivated by something different from the real science).
3.
BTraven 08/23/2010
Zitat von GeraldoLinoThe kernel of all this stuff is related to a simple application of the scientific method to the anthropogenic warming hypothesis. The hypothesis is that Mankind is affecting the climate dynamics with its carbon emissions released since the 18th century Industrial Revolution. In order to corroborate it there would have to be at least some perceivable and conspicuous changes in the evolution of certain climate parameters like temperatures, or climate-influenced factors like the sea level, as compared to their behaviour before the Industrial Revolution, in such a way that the human interference could be clearly identified. Such conspicuous index of change would be the long sought after “smoking gun” of the anthropogenic hypothesis. On to the facts: according to the 2007 IPCC report (AR4), the average atmospheric temperature has increased 0.8 degree centigrade, and the sea level has raised 0.2 m since 1870. Well, it happens that during the Holocene, the 12,000 years-old geological epoch in which our Civilization has existed, there have been several periods hotter than the current one and sea levels also higher than the current ones. For example, during the Middle Holocene, some 5,000-6,000 years ago, the sea levels were 3 to 4 meters higher than the current ones, while the average temperatures were at least 2 degrees centigrade higher, as indicated by hundreds of researches carried out in dozens of countries and in all continents. Also, the temperature rise since 1870 means a rising rate of 0.06 degree centigrade per decade, one order of magnitude lower than the warming transition to the Holocene 12,000 years ago, when the temperatures raised 6-8 degrees centigrade in less than a century. Well, dung and firewood were the only fuels used by Mankind during the Middle Holocene. If there were higher temperatures and sea levels then, and if the global warming was much faster 12,000 years ago, hence it is simply not possible to distinguish the little variations occurred since the late 19th century from the much wider natural oscillations that happened before. The only conclusion arising from these facts is that the anthropogenic hypothesis has no basis in the real world evidences, remaining a mere fabrication from mathematical models. As a corollary, any proposal of changing the entire energy structure of the world economy, which is 80% dependent from fossil fuels, can only be regarded as preposterous (or motivated by something different from the real science).
Please, inform me, which civilisation lived during the Middle Holecene. Were it forced to relocate its cities because of the rising water level of the oceans? It makes no sense to claim that there was a time when it had been much worse when nobody was affected. It sounds a bit nerdy to resort to such examples.
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About Hans Joachim Schellnhuber

DBU
Physicist Hans Joachim Schellnhuber, 60, is a world famous physicist and climate researcher. After working in Germany and California, he was appointed founding director of the Potsdam Institute for Climate Impact Research (PIK) in 1991, which he still leads today. He is an adviser to German Chancellor Angela Merkel on climate-related issues as chair of the German Advisory Council on Global Change (WBGU).


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