The 5-year mean global temperature has been flat for the last decade, which we interpret as a combination of natural variability and a slow down in the growth rate of net climate forcing.

How long have we got? We have to stabilize emissions of carbon dioxide within a decade, or temperatures will warm by more than one degree... We don't have much time left.

Coral reefs, the rain forest of the ocean, are home for one-third of the species of the sea. Coral reefs are under stress for several reasons, including warming of the ocean, but especially because of ocean acidification, a direct effect of added carbon dioxide. Ocean life dependent on carbonate shells and skeletons is threatened by dissolution as the ocean becomes more acid.

Money has too big an influence on our politics in Washington and somehow we need to do something about that.

I've tried to be a straight scientist doing the science and reporting it as best I can.

Several times in Earth's history, rapid global warming occurred, apparently spurred by amplifying feedbacks. In each case, more than half of plant and animal species became extinct. New species came into being over tens and hundreds of thousands of years. But these are time scales and generations that we cannot imagine.

The evidence for human-made climate change is overwhelming.