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

Success underwater depends mostly on how you conduct yourself. Diving can be the most relaxing experience in the world. Your weight seems to disappear. Space travel will be available only to a few individuals for some time, but the oceans are available to almost everyone - now.

There are now more than 4,000 places in the sea around the world that have some kind of protection. The bad news: You have to look hard to find them. What you find instead is destructive fishing, mining, gas and oil exploration.

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."

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

The burning of fossil fuels has altered the amount of carbon dioxide in the atmosphere so rapidly and so abundantly that now, we are driving not just the warming trend, not just the sea level rise that is a consequence of the warming trend that is melting polar ice and alpine ice, but also [ocean acidification].

The Arctic is a place that historically, during all preceding human history, has largely been an icy realm with an impact on ocean currents. That, in turn, influences the temperature of the planet. The Arctic is now vulnerable because of the excess carbon dioxide in the atmosphere, with a rate of melting that is stunning.