Study quantifies link between greenhouse gases, polar bear survival

Washington (AFP) - Polar bears have long symbolized the dangers posed by climate change, as rising temperatures melt away the Arctic sea ice they depend upon for survival. But quantifying the impact of a single oil well or coal power plant on the tundra predators had eluded scientists, until now. A new report published in the journal Science on Thursday shows it is possible to calculate how much new greenhouse gas emissions will increase the number of ice-free days in the bears' habitats, and how that in turn will affect the percentage of cubs that reach adulthood. By achieving this level of g...