Klimaat-modellen onderschatten opwarming aarde

Door Joe Romm, Climate Progress, 17 juli 2009

A new PETM study is out (click here ) - which rational climate science activists understand is yet more evidence that most climate models underestimate likely future warming. Here is the Union of Concerned Scientists press release on the study:

'Several climate contrarian Web sites are misrepresenting the findings of a peer-reviewed study published in the July 13 issue of the journal Nature Geoscience. The study - by scientists from Rice University, the University of Hawaii and the University of California at Santa Cruz - provides evidence that current climate models are underestimating the amount of warming that an increase in atmospheric carbon dioxide can cause. In other words, the potential consequences of global warming are likely worse than what scientists are predicting.

The study examined the extent to which increased carbon dioxide levels could explain a 5 to 9 degree Celsius increase the Earth experienced 55.5 million years ago. The authors concluded that current estimates of how much carbon dioxide increases the average Earth temperature only explains 3.5 degrees of warming.

In a commentary published with the study, David Beerling, a paleobiologist at the University of Sheffield in England, writes: 'The upshot of the study. is that forecasts of future warming could be severely underestimating the extent of the problem that lies in store for humanity as greenhouse gases accumulate in the atmosphere.'

The study’s authors themselves note in the conclusion:

'Possible causes of the excess warming include increased production and levels of trace greenhouse gases as a consequence of the climatic warming (such as CH4)'.