Can we still avert climate chaos?

Nasa's James Hansen was the first to point out the perils of climate change to the US Congress. In The Observer today, he began a heated debate with experts from around the world, from China to the threatened Maldives, and argued that our leaders had to be shaken out of their complacency. But will they show enough courage at next week's Copenhagen summit to take the first steps to saving the planet? Read more here.