Change your diet, polar bear

World temperatures have been relatively stable for the last 17 years but now, according to the meteorologists, they are rising again.

This year and last, they predict, will be the warmest on record. The effects of global warming are most pronounced close to the poles; conditions there are changing rapidly. Areas ice-bound a few years ago are now clear, cruise-ships are negotiating the notorious Northwest Passage while, in Alaska, houses are sinking as the permafrost thaws beneath them. If humans are affected by climate change, how much more so are plants and animals?

Scientists at the University of Santa Barbara modelled the likely effects of ocean warming on 13,000 species. Many plants and animals, their research shows, will relocate towards the poles. But how will those already living in the far north cope? Some mammals seem to be changing their lifestyles. Perhaps Arctic creatures are more adaptable than we think.