We need to put a price on carbon, and that's what cap-and-trade does and that's also what a CO2 tax does. As long as our current valuation in the marketplace tells us every minute of every day that it's perfectly all right to dump 90 million tons of global warming into the thin atmosphere surrounding the planet every 24 hours as if that atmosphere is an open sewer, then the individual actions are not going to solve the problem.

The conversation on global warming has been stalled because a shrinking group of denialists fly into a rage when it's mentioned.

Each and every one of us can make changes in the way we live our lives and become part of the solution [to climate change]

The truth is that climate change is presenting the greatest challenge humanity has ever faced.

The role of campaign contributions in our political system and the role of lobbyists have now reached levels that are quite unhealthy for the operations of our democracy. But the antidote, as in past eras of lobbyist excess, is for more involvement by citizens to build pressure on members of the House and Senate to serve the public interest.

The moral imperative to make big changes is inescapable...that what we take for granted may not be here for our children

We sometimes emphasize the danger in a crisis without focusing on the opportunities that are there.