The climate has been changing. Of course it [has]. Evidence throughout history, [which] we can assess, especially during human history, shows there have been ups and downs. But the last ten thousand years have been relatively stable compared to now.

If you make the choice to just go with the flow, that is a choice to make a difference in a negative way.

Throughout all of human history we've enjoyed certain benign circumstances: an envelope of atmosphere, an envelope of temperature. A kind of resilience that if you cut down trees, then they'll grow back. You take fish, they recover. You put stuff into the atmosphere that you know is not good for us, but we can still breathe. We haven't awakened, generally, to the sense of urgency that does exist.

My first breath was just...it just seemed impossible that you could actually breathe underwater. I knew in my mind it was possible, but actually experiencing it was such a gulp of joy and I feel it every time I go under the ocean. I love doing it, to be able to feel weightless, to spin on one finger, to do somersaults, to be like a graceful ballerina - even with a huge tank on your back you can do the most extraordinary things.

We still have the illusion that the ocean will recover. That even if we do have to lose sharks, people don't understand why this matters. The evidence is in front of us, and we fail to take it in and say, "Now I get it. Now I understand."

Life in the ocean makes Earth hospitable. We are sailing along in the universe and we have a blue engine that is making everything alright.

The concept of 'peak oil' has penetrated the hearts and minds of people concerned about energy for the future. 'Peak fish' occurred around the end of the 1980s.