As I have said for many years throughout this land, we're borrowing money from China to buy oil from the Persian Gulf to burn it in ways that destroy the future of human civilization. Every bit of that has to change.

There are many who would much prefer that the word 'climate' never be mentioned and that the issue be eliminated from our national conversation.

The consensus is clear. We need an immediate and determined shift to a clean, renewable economy. The continued mass burning of fossil fuels is inconsistent with a healthy, prosperous future for our civilization.

Every nation has a moral obligation to safeguard the future.

The cumulative amount of man-made global pollution that's in the atmosphere now traps as much extra heat energy every day as would be released by 400,000 Hiroshima-class atomic bombs exploding every day. It's a big planet, but that's an awful lot of energy.

As human beings, we are vulnerable to confusing the unprecedented with the improbable. In our everyday experience, if something has never happened before, we are generally safe in assuming it is not going to happen in the future, but the exceptions can kill you and climate change is one of those exceptions.

I have always been fascinated with those who try to look over the horizon and see things that are coming at us.