There is this sweet spot in time when we have an opportunity to stop killing sharks and tunas and swordfish and other wildlife in the sea before it's too late.

Health to the ocean means health for us.

The most important thing for people to know about the governance of the Arctic is that we have a chance now to act to maintain the integrity of the system or to lose it. To lose it means that we will dismember the vital systems that make the Arctic work. It's not just a cost to the people who live there. It's a cost to all people everywhere.

It isn't too late to shift from the swift, sharp decline of ocean systems in recent decades to an era of steady recovery. There is time, and there is a growing awareness, which is the best way to counter indifference. People who know might care.

We're still under the weight of this impression that the ocean is too big to fail, that the planet is too big to fail.

I've spent thousands of hours under water. And even in the deepest dive I have ever made, 2.5 miles (about 4 kilometers) down, I saw trash and other tangible evidence of our presence.

Forty percent of the United States drains into the Mississippi. It's agriculture. It's golf courses. It's domestic runoff from our lawns and roads. Ultimately, where does it go? Downstream into the gulf.