We are close to a time when all of humankind will envision a global agenda that encompasses a kind of Global Marshall Plan to address the causes of poverty and suffering and environmental destruction all over the earth.

I have felt for a long time that the pathway to solving the climate crisis is through the building of a massive grassroots army of men and women who will go out there and win the conversation on climate, and persuade businesses, and universities, and towns to switch to renewable energy and to reduce emissions. And the big change from ten years ago is that people are way more receptive, not only to the message that we have to act, not only to the message that now we can act, we have the solutions now - that's the biggest change - but also willing to make a commitment that we will act.

It's as if we think the laws of physics are subject to debate and amendment and political contributions can sway the laws of physics.

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.

When you look at what has happened over the last few decades the natural fluctuations point in the opposite direction of what has actually occurred. When they run the models and plug in the man-made pollution, the correspondence is exact. Beyond that, the scale of natural fluctuations has now been far exceeded by the impact of man-made global warming.

Political will is a renewable resource, and everyone can have it in abundance if they so choose.

I just think that a much more important part of the problem we face, which was evident 10 years ago and is even more evident now, is that the way we share information among ourselves as American citizens has been radically transformed. The line between news and entertainment has almost dissolved, where ratings now have a big impact on what kinds of stories are covered and not stories.