I'm haunted by the thought of what Ray Anderson calls 'tomorrow's child,' asking why we didn't do something on our watch to save sharks and bluefin tuna and squids and coral reefs and the living ocean while there still was time. Well, now is that time.

In the past few decades, Earth's natural systems have endured more pressure than in all preceding human history.

Many of us ask what can I, as one person, do, but history shows us that everything good and bad starts because somebody does something or does not do something.

Ocean acidification - the excess carbon dioxide in the atmosphere that is turning the oceans increasingly acid - is a slow but accelerating impact with consequences that will greatly overshadow all the oil spills put together. The warming trend that is CO2-related will overshadow all the oil spills that have ever occurred put together.

Health to the ocean means health for us.

I've always said, 'Underwater or on top, men and women are compatible.'

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.