Far and away, the greatest threat to the ocean, and thus to ourselves, is ignorance. But we can do something about that.

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.

Fortunately, we know more about the problems that we have than in all preceding history. We know now the consequences of the things that we put into the air, into the water - of the way we treat life on Earth.

Places change over time with or without oil spills, but humans are responsible for the Deepwater Horizon gusher - and humans, as well as the corals, fish and other creatures, are suffering the consequences.

When I write a scientific treatise, I might reach 100 people. When the 'National Geographic' covers a project, it communicates about plants and fish and underwater technology to more than 10 million people.

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 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.