German Climatologist on Criticism of IPCC: 'We Received a Kick in the Pants' - SPIEGEL ONLINE - News - International

[German physicist Hans Joachim Schellnhuber] 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.
...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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SPIEGEL: But the public has gained the impression that superstorms with previously unheard of destructive power will devastate our cities in the future. Shouldn't climatologists at least make it clear that they are still largely in the dark?

Schellnhuber: The simple answer is yes. In fact, we are very much in the dark on this issue. On the other hand, that fact is by no means reassuring.
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Schellnhuber: Believe it or not, I don't practice self-censorship, and as a physicist, I'm accustomed to recognizing that new studies might correct my point of view, even if this translates into intellectual defeat. I wouldn't hesitate to tell the chancellor that there is a new study that suggests we are all backing the wrong horse and that humans are not to blame for climate change. Or perhaps we'll discover in 20 years' time that we can easily master a five-degree increase in global temperatures. I would be very happy about that. But from today's perspective there is no reason for such optimism.
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SPIEGEL: Why then have you, as one of the creators of the two-degree target, imposed such a magical limit to which all countries must slavishly adhere?

Schellnhuber: Politicians like to have clear targets, and a simple number is easier to handle than a complex temperature range. Besides, it was important to introduce a quantitative orientation in the first place, which the 1992 Framework Convention on Climate Change managed to elegantly wangle its way out of. And let's be honest: Even if we aim for the two-degree target, we'll end up somewhat higher. Whenever there's a speed limit, most drivers tend to go a little faster.