Explain how polar bears may be indicators to climate change. Includes the words atmosphere and greenhouse gas.

The loss of sea ice affects polar bears ability to find food studies show. Polars bears feed in ringed seals that live at the ice edge, getting two thirds of the energy they need for the entire year in late spring and early summer. With the ice retreating earlier in spring and forming later in winter, the bears have time to hunt prey and have to go without food for longer