Réchauffement climatique, Katrina et les dés pipés

Je vous ai dit tout le bien que je pense de realclimate.org dans ce billet la semaine dernière. Les scientifiques derrière ce blog nous ont pondu un autre article de grand intérêt avec Katrina comme toile de fond. Je n'ai pas les connaissances scientifiques nécessaires pour vous résumer intelligemment cet article, mais j'essaie quand même en trois lignes:

- C'est un fait scientifique, le climat se réchauffe.
- On ne peut pas lier directement Katrina à ce réchauffement.
- Cependant, il semble que le réchauffement influence déjà, à la hausse, la puissance des ouragans.

Citation:

[...]As we have also pointed out in previous posts, we can indeed draw some important conclusions about the links between hurricane activity and global warming in a statistical sense. The situation is analogous to rolling loaded dice: one could, if one was so inclined, construct a set of dice where sixes occur twice as often as normal. But if you were to roll a six using these dice, you could not blame it specifically on the fact that the dice had been loaded. Half of the sixes would have occurred anyway, even with normal dice. Loading the dice simply doubled the odds. In the same manner, while we cannot draw firm conclusions about one single hurricane, we can draw some conclusions about hurricanes more generally. In particular, the available scientific evidence indicates that it is likely that global warming will make - and possibly already is making - those hurricanes that form more destructive than they otherwise would have been.