Especially in recent years, the more and more we understand what we are doing, the more we have the science to tell us what we're doing, the fact that we continue to do it without taking steps to address it strikes me as, among many other things, irreverent in an extreme.

All the things that we've done as a species have had a limited scope. We're talking about melting the ice caps, raising the level of the seas dramatically, changing the distribution of every other species on Earth, perhaps wiping out one-third or half of them. The changes at work are geologic in scale. The level of change required to deal with it is enormous, too. It will require change in every country. It will require a degree of global cooperation that we haven't seen before.

The consumer culture in general has washed over our civilization. For the last 50 years, if you've had a credit card and some access to money, you don't really need neighbors around you. And as a result, they dwindled. The average American has half as many close friends as they did in 1950. Three quarters of Americans don't know their next-door neighbor. They may know their name, but they have no real relationship with them. That's an utterly new place for human beings to find themselves in - I mean, we're a socially evolved primate.

After a lifetime of nature shows and magazine photos, we arrive at the woods conditioned to expect splendor - surprised when the parking lot does not contain a snarl of animals attractively mating and killing each other.

The roof of my house is covered in solar panels. When Im home, Im a pretty green fellow.

We're putting more carbon into the atmosphere than the atmosphere can absorb. And everybody told us when we started, coz we knew nothing when we started - we still don't know very much - but everybody told us 'this is crazy, you don't use a scientific data point, it's a number, people don't respond to numbers'.

Do I think that people should in the best of all possible worlds have to go to jail for wanting the US government to pay attention to the warnings of scientists about climate change? Not really. I mean, in a rational world, if all the scientists said, "The worst thing that ever happened is about to happen and here's what you should do to stop it," you would expect any rational system to say, "Oh, sure, OK, let's do something about it." But that's not the world we live in. In the world we live in, you do need people willing to stand up, fight, march and sometimes go to jail.