It's as if we think the laws of physics are subject to debate and amendment and political contributions can sway the laws of physics.

We're operating this planet like a business in liquidation.

The Himalayan Glaciers on the Tibetan Plateau have been among the most affected by global warming. The Himalayas...provide more than half of the drinking water for 40% of the world's population...Within the next half-century, that 40% of the world's people may well face a very serious drinking water shortage, unless the world acts boldly and quickly to mitigate global warming.

The existence of the EPA regulation will require large carbon polluters to look at their hole cards, and some of them have decided that they much prefer legislation.

A day will come when our children and grandchildren will look back and they'll ask one of two questions. Either they will ask: "what in God's name were they doing?" or they may look back and say: "how did they find the uncommon moral courage to rise above politics and redeem the promise of American democracy?"

I don't have the illusion that there's any position or role in the world with as much potential for bringing about change as that of president of the United States.

Hurricane Sandy is a disturbing sign of things to come. We must heed this warning and act quickly to solve the climate crisis. Dirty energy makes dirty weather.