People are finally able to look around and say, 'I can see the drought, I can see the rising sea levels, I can see the crops dying. Okay, now I get it.' It is finally beginning to sink in that there has been a lot of damage.

He has the attention span of a lightning bolt.

Have a strong vision about the story you want to tell and how you want to tell it.

Hollywood was not a place I dreamed of getting to. I never could take seriously the obsession people have about being a celebrity or getting to Hollywood - I was born next door.

I try to avoid giving advice. The only advice I will give is to pay attention. I don't mean to the screen in your hand. I'm talking about the natural world. I spent a lot of time educating my children about nature by putting them in nature. I said, "I want you to listen; I want you to look." There's so much technology coming into our lives that takes us away from the natural stuff, so I'm pushing the other way.

The way I deal with arthritis is to keep moving. As long as I can play hard tennis, as long as I can ski or ride a horse - all kinds of things can come your way. As long as you can, do it. People who retire die. My dad retired and died shortly after. Just keep moving.

I think documentary filmmakers need as much protection as possible under journalist's privilege. How else is the public to know what is going on?