The Arctic Ice Crisis
There's no place on Earth that's changing faster – and no place where that change matters more – than Greenland. Late last month, NASA reported that ice all across the vast glacial interior of the world's largest island was melting – a "freak event" that hadn't occurred for at least 150 years. The alarming discovery briefly focused the media's attention on a place that rarely makes headlines. RAPID ICE MELT BAFFLES SCIENTISTS, The Wall Street Journal declared.
In fact, scientists weren't baffled at all – a paper published just weeks before had predicted that an abrupt, islandwide melt was imminent. The rapid loss of ice is only the latest in a chain of events that have upended conventional understanding of how the Earth's "cryosphere" – its frozen places – behave. Taken together, the events offer new insight into how fast the world's seas are likely to rise as a result of global warming – and hence, the fate of major cities like New York and Miami and Mumbai.
Jason Box, a scientist at the Byrd Polar Research Center, has probably spent more time in Greenland than any American of his generation. He began his yearly treks to the island in the 1990s as an undergraduate at the University of Colorado, helping his professor install a series of automated weather stations; last month he was sleeping on a sailboat near the mouth of a huge glacier and traveling onto the ice by helicopter to install yet more sensors. The shift he and his team have measured over the course of the past two decades is startling. "When I took my first course in glaciology," Box says, "conventional thought had the reaction time of the ice sheets to heating on the order of 10,000 years." The ice sheet, scientists believed, was a mostly inert ice cube frozen fast at its bed; if the glaciers melted because of global warming, the process would be, well, glacial.
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But the future, pressing as it is, sometimes gives way to sheer awe at the scale of what we've already done. Simply by changing the albedo of the Greenland ice sheet, Box calculates, the island now absorbs more extra energy each summer than the U.S. consumes in a year. The shape and color of the ice sheet's crystals, in other words, are trapping more of the sun's rays than all the cars and factories and furnaces produce in the world's biggest economy. One of Box's collaborators, photographer James Balog, puts it like this: "Working in Greenland these past years has left me with a profound feeling of being in the middle of a decisive historic moment – the kind of moment, at least in geologic terms, that marks the grand tidal changes of history." Amid this summer's drama of drought, fire and record heat, the planet's destiny may have been revealed, in a single season, by the quiet metamorphosis of a silent, empty sheet of ice.
Read more: http://www.rollingstone.com/politics/news/the-arctic-ice-crisis-20120816#ixzz23pqUwrl3
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