I hope that someday we will find evidence that there is intelligent life among humans on this planet.

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.

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.

When you think about the real cost of so-called cheap energy that has driven our prosperity to unprecedented levels, for some of us, to our horror, we've realized that this has the potential for burning brightly and then snuffing out.

Throughout all of human history we have consumed the natural world. All creatures do. Birds do. Fish do. Earthworms do. We consume the natural world as a source of our survival. But no creature has ever consumed at the scale that humans have, and now there are seven billion of us. I think the good news is that a large percentage of those seven billion minds can work to make better decisions.

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.

Every time I slip into the ocean, it's like going home.