new york — the extent of arctic sea ice this week shrunk to a new low in the era of satellite record-keeping that began in 1979. the increased expanse of water near the top of the world could have implications for global shipping, wildlife and even international diplomacy.
polar bears hunt seals from sea ice, but could drown if forced to swim long distances in open water. satellite photos released by america’s space agency, nasa, illustrate the daunting threat to such bears. an image shows the amount of arctic sea ice in 1979. another shows the recor
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