A study published reports that the shifts in the timing and duration of ice cover, especially the possible lengthening of ice-free periods, may impact polar bears under projected warming.
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Shifts away from multiyear ice to annual ice cover throughout the region, as well as lengthening ice-free periods, may become critical for polar bears before the end of the 21st century with projected warming. Each polar bear population in the Archipelago may undergo 2-5 months of ice-free conditions, where no such conditions exist presently. Under business-as-usual climate projections, polar bears may face starvation and reproductive failure across the entire Archipelago by the year 2100. "We predict that nearly one-tenth of the world's polar bear habitat, as much as one-quarter of their global population, may undergo significant habitat loss under business-as-usual climate projections," said Stephen Hamilton.
Source-Eurekalert