The rise in the surface temperature of earth has been markedly slower over the last 15 years than in the 20 years before that. And that lull in warming has occurred even as greenhouse gases have accumulated in the atmosphere at a record pace.
The slowdown is a bit of a mystery to climate scientists. True, the basic theory that predicts a warming of the planet in response to human emissions does not suggest that warming should be smooth and continuous. To the contrary, in a climate system still dominated by natural variability, there is every reason to think the warming will proceed in fits and starts.
Já o galã Robert Redford não se deixa enganar e pressiona Obama para assumir a coragem das suas convicções.