I think all countries need to aim to cut the CO2 emissions per person, taking account of externalities like imports and exports.
Martin ReesAll the atoms we are made of are forged from hydrogen in stars that died and exploded before our solar system formed. So if you are romantic, you can say we are literally stardust. If you are less romantic, you can say we're the nuclear waste from fuel that makes stars shine.
Martin ReesOne of the computer models for a four degree temperature rise would give rise to a 10 degree temperature rise in Africa. And bear in mind also that in the depth of an ice age the mean temperature drop compared to the present was five degrees.
Martin ReesCosmology does, I think, affect the way that we perceive humanity's role in nature. One thing we've learnt from astronomy is that the future lying ahead is more prolonged than the past. Even our sun is less than halfway through its life.
Martin Rees