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.

My parents moved to Florida when I was 12, and my backyard was the Gulf of Mexico.

We are all together in this, we are all together in this single living ecosystem called planet earth.

We woke up some years ago about the consequences of ozone depletion, the hole in the atmosphere. You can't see it. You can't taste it. You can't smell it. But now we do regard that as a key issue. It's a scientific finding.

We have been far too aggressive about extracting ocean wildlife, not appreciating that there are limits and even points of no return.

Throughout all of human history we've enjoyed certain benign circumstances: an envelope of atmosphere, an envelope of temperature. A kind of resilience that if you cut down trees, then they'll grow back. You take fish, they recover. You put stuff into the atmosphere that you know is not good for us, but we can still breathe. We haven't awakened, generally, to the sense of urgency that does exist.

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.