Time: When it comes to polar melting, the Arctic hogs all the attention. And not without reason--last summer Arctic sea ice melted to its smallest extent on record, 49% below the 1979-2000 average. During the first two weeks of July, sea ice declined 61% faster than the 1981-2000 average, according to the National Snow and Ice Data Center. As sea ice melted, Arctic shipping set a record, with trips quadrupling in 2013 from the year before. The Arctic permafrost--the frozen soil that covers much of the...