"The shrinkage of the sea ice is no less a result of human hands than the ploughing of the prairies. It might even turn out as lucrative. But the costs will also be huge. Unique ecosystems, and perhaps many species, will be lost in a tide of environmental change. The cause is global pollution, and the risks it carries are likewise global. The Arctic, no longer distant or inviolable, has emerged, almost overnight, as a powerful symbol of the age of man."
Very good piece in the Economist about the opportunities and dangers of the melting Arctic.