We're mathematically past the point where the accumulation of individual actions can add up quickly enough to make a difference. The individual action that actually matters is not being an individual. It's joining together with other people in groups large enough to change the political dynamic around climate change.

All the science in the last few years, or almost all of it, really serves to show that the [climate] effects are larger and more rapid than we had thought even a decade ago.

We have to get our states to adopt what are called "renewable portfolio standards" pledging to use a lot of renewable energy by 2015 or 2020. We have to work with businesses and shops to get them engaged in the same way.

I think [George W.] Bush has done nothing right about global warming.

On the top of these mile thick slabs of ice the water is percolating quickly to the base and greasing the skids, as it were, for the slide of that ice into the ocean.

If Apple is enslaving Chinese to make its iPhones, you don't need to eat the i-Phone, you need to make sure that Apple is paying a living wage to someone, and then it adds a dollar to the cost of iphones, and everybody's cool.

We finally know where the red line for climate really is. After the rapid melt of arctic ice in the summer of 2007, our best scientists, led by NASA's Jim Hansen, went back to work and produced a series of papers showing that with more than 350 ppm (parts per million) of carbon dioxide in the atmosphere, we couldn't have a planet "similar to the one on which civilization developed and to which life on earth is adapted."