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.

Burning fossil fuels has given us the gift of seeing ourselves in new ways. But that very gift now enables us to see we've got to change our ways.

The image of Earth from space transformed our view of ourselves. It is maybe the most important image that exists - because we can see ourselves in context in a way that otherwise would be really hard to explain. It should inspire us to wonder about it, to want to know everything we can about it and do everything we can to take care of it.

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.

Some experts look at global warming, increased world temperature, as the critical tipping point that is causing a crash in coral reef health around the world. And there's no question that it is a factor, but it's preceded by the loss of resilience and degradation.

As a child, I was aware of the widely-held attitude that the ocean is so big, so resilient that we could use the sea as the ultimate place to dispose of anything we did not want, from garbage and nuclear wastes to sludge from sewage to entire ships that had reached the end of their useful life.

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.