As a student of conservation biology, I believe that characteristics with survival value will ultimately prevail. There is no survival value in pessimism. If you think failure is inevitable, that view will probably become self-fulfilling.

Build high-speed, electrified trains over the most-traveled corridors. It'sreally hard to power carbon-free airplanes, but electrified trains are much easier. We'll be a half century behind the Japanese, but better late than never.

f the government is going to put money into the automobile sector, it should break up GM and Chrysler as a condition of financial aid, and it should be even-handed in its treatment of start-up firms like Tesla, Miles, Fisker, and others. It would be terrible to kill the entrepreneurs who have taken great risks to bring new automotive technologies to market by pumping tax dollars into the behemoths that have done everything wrong for the last years.

The easiest way to make something cool is to get cool people to do it. Part of this might mean the president has to forget tensions with opponents, or people like Arnold Schwarzenegger who has actually been decent with oil issues. Maybe he needs to pull some of the cool people in and make them model the right behaviors.

That said, I'm embarrassed and furious that so many coal-state Democrats in the U.S. Senate are paralyzing international progress to protect the short term interests of a dying industry that ravages the environment from mine to slag heap.

By the year 2000, such renewable energy sources could provide 40 percent of the global energy budget; by 2025, humanity could obtain 75 percent of its energy from solar resources.

We've made some heroic efforts, but the Earth as a whole is in worse shape today than 30 years ago, ... There's been 30 more years of greenhouses gases, species extinctions and population growth.