Is it too late to save the Arctic? 13 December 06

You could call it A-Day - a sort of D-Day in the Arctic. It's the day the last fragment of ice disappears and the whole of the polar Arctic ocean - a shimmering white wasteland for more than a million years - becomes no more than open water.

Previous scientific predictions suggested that it might happen in about 2080. But, as so often seems to be the case with global warming science, the worst-case scenario just got worse. The latest scientific modelling, by the US-based National Centre for Atmospheric Research, has brought the final melt date forward by 40 years. We can now expect A-Day to happen by 2040.

This is bad news for polar bears, who will drown or starve long before the last ice floe trickles away. And without the “solar mirror” of Arctic ice, much more of the sun’s heat will be absorbed by the planet, boosting global warming still further. This could push the Earth past the “tipping point” beyond which climate change becomes effectively unstoppable.

So is there still time to save the Arctic? Probably not. This year scientists discovered that a sixth of the entire ice cap melted away in the space of a single summer, between 2004 and 2005. We have already pushed atmospheric carbon dioxide to levels which are unprecedented in 20m years, so in one sense temperatures are only catching up.

However, greenhouse gas emissions are the one part of the equation humanity can actually control. We can’t do anything to stop the Arctic melting directly, but we can stop pumping out ever more of the gases that we know beyond doubt will make things warmer still.

It always makes sense to take your foot off the accelerator, especially if the cliff is even closer than you thought.

First published in the Guardian. Original article free to view here