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This photograph from July 4, 2010, shows NASA scientists carefully navigating the Arctic melt ponds and sea ice in the Chukchi Sea. On a five-week field trip as part of NASA's ICESCAPE Mission (Impacts of Climate change on the Eco-Systems and Chemistry of the Arctic Pacific Environment), a multi-year shipborne project, these scientists were sampling the "physical, chemical and biological characteristics of the ocean and sea ice," according to NASA.

Situated between Russia and Alaska, the Chukchi Sea is typically navigable for only about one-third of the year. As the climate warms, though, and more carbon dioxide is absorbed by the oceans, that period is growing. While a welcome change for fishermen in the area, it's made life difficult for the polar bears, one of five distinct Eurasian populations of the species.

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Image: NASA.

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