There's a part of all of us whose impulse is to say, "Let's keep everything the same until I die and then you can do whatever you want afterward." And that's a difficult part.

We finally know where the red line for climate really is. After the rapid melt of arctic ice in the summer of 2007, our best scientists, led by NASA's Jim Hansen, went back to work and produced a series of papers showing that with more than 350 ppm (parts per million) of carbon dioxide in the atmosphere, we couldn't have a planet "similar to the one on which civilization developed and to which life on earth is adapted."

In the scientific community, the debate is over, for all intents and purposes, about whether or not the planet is heating and who is causing it. In fact, it's more or less been over since 1995.

We just see a sort of cascading amount of data of the damage that is being done by those increased temperatures.

Most of the men and women who vote in Congress each year to continue subsidies have taken campaign donations from big energy companies.

Look - every time is the wrong time and the perfect time to have a kid, and you just do it when you can.

In the last two years 24 countries have set new all-time temperature records. We've seen flooding on an epic scale in every continent .