A major new study says the Arctic is warming up at twice the pace of the rest of the planet, and warns that as early as 2050 all sea and coastal ice may disappear during the summer months. The report by more than 200 scientists concluded that large scale climate change is under was and would accelerate unless action is taken. In some places it finds the ice has virtually halved in thickness over the last 30 years. Computer models suggest that of trends continue, at some points, there will simply be no ice at all in summer months. That could come as early as 2050, through more likely a few decades later. People in the Arctic will feel a mixed impact from the warning. Staple food such as fish may disappear, on the other hand, the newly open ocean may enhance trade opportunities.