Freeman Dyson ist einer der weltweit renommiertesten Physiker und ein bahnbrechender Kosmologe. Er ist zugleich ein wissenschaftlicher Berater der Global Warming Policy Foundation. Scientific American berichtet, warum einer der grössten Wissenschaftler unserer Zeit, Zweifel an der allgemeinen Klimahysterie hegt: Eminent physicist Freeman Dyson raised eyebrows a month ago when he told the New York Times Magazine that a little extra carbon dioxide—and global warming—might turn out to be good for the planet. So when we saw his name on an event around the corner from Scientific American’s offices we figured we’d go hear his criticisms, dubbed “Climate Disasters, Safe Nukes and Other Myths,” firsthand.

At the luncheon put on by the Cato Institute, when the talk turned to climate change Dyson started out sounding as if the whole thing was overblown, noting that the prospect of global warming is a problem that should be taken seriously. But he also said that no one should be alarmed about it yet.

Then he outlined his main criticism: Too much of the science of climate change relies on computer models, he argued, and those models are crude mathematical approximations of the real world. After all, a simple cloud—small in scale, big in climate effects, the product of evaporation and condensation, all of which it is difficult to create equations for—eludes the most sophisticated climate models.

So climate modelers turn to what they call parameters or, as Dyson likes to call them: “fudge factors.” These are approximations, such as the average cloudiness of a particular spot at a particular time, that are then applied globally. With the help of about 100 of these parameters, models can now closely match the world’s present day climate, Dyson says. These models then, like the one developed at Princeton University where Dyson is a professor emeritus, are “useful for understanding climate but not for predicting climate.”

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