Very few people on earth ever get to say: 'I am doing, right now, the most important thing I could possibly be doing.' If you'll join this fight that's what you'll get to say

One degree turns out to be enough to really unhinge all sorts of earth's ecosystems.

In 50 years, no one will care about the fiscal cliff or the Euro crisis. They'll just ask, "So the Arctic melted, and then what did you do?"

The most blatant examples are increased power and frequency in hurricanes and the increased depth and frequency of heat waves.

If one wanted to stigmaitise, that's how one would do it - lots and lots of people saying "we're severing our ties".

We have to transition to new technologies, making it more expensive to continue with the old and polluting technologies and cheaper to go to the clean ones.

I'm probably the wrong person to ask. My partner in much of this work [climate movement], who really came up with the divestment campaign with me, Naomi Klein, I think has written powerfully about this.