I've tried to be a straight scientist doing the science and reporting it as best I can.

We're running out of time.

Imagine a giant asteroid on a direct collision course with Earth. That is the equivalent of what we face now with climate change, yet we dither.

We are on the precipice of climate system tipping points beyond which there is no redemption.

It would be immoral to leave young people with a climate system spiraling out of control.

Global warming has already triggered a sea level rise that could reach from 6 metres (19.69 ft) to 25 metres (27.34 yards).

What we are doing to the future of our children, and the other species on the planet, is a clear moral issue.

How long have we got? We have to stabilize emissions of carbon dioxide within a decade, or temperatures will warm by more than one degree... We don't have much time left.

What has become clear from the science is that we cannot burn all of the fossil fuels without creating a very different planet.

It's as certain that as long as fossil fuels are the cheapest energy, we will just keep burning them.

We have at most ten years—not ten years to decide upon action, but ten years to alter fundamentally the trajectory of global greenhouse emissions.

You have power over your mind - not outside events. Realize this, and you will find strength.

It is actually okay to stop trying to solve the problem of feeling bad. In fact it is wise because our habitual ways of solving problems almost invariably wind up making things worse.

Time can be an ally or an enemy. What it becomes depends entirely upon you, your goals, and your determination to use every available minute.

As long as we rationalize nuclear weapons as "necessary" in order to save American lives, then nuclear weapons will never be gotten rid of.

The whole process of writing a novel is having this great, beautiful idea and then spoiling it.

Preparing for battle, plans were essential. But once the battle was joined, plans were useless.

Half-truths are like half a brick - they can be thrown farther.

Don't be too proud to take lessons. I'm not.

But when one believes in the reality of things, making them visible by artificial means is not quite the same as feeling that they are close at hand.

You can’t answer what I said, so you’re going to talk about my saying it.