Bearing the Changes

Photograph by Paul Souders

"A polar bear peers up from beneath the melting sea ice on Hudson Bay as the setting midnight sun glows red from the smoke of distant fires during a record-breaking spell of hot weather," writes Paul Souders, who submitted this winning picture to the 2013 National Geographic Photo Contest . "The Manitoba population of polar bears, the southernmost in the world, is particularly threatened by a warming climate and reduced sea ice."

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