Greenland’s glaciers are melting far faster than scientists expected
The Arctic Ice Crisis
by: Bill McKibben
Rolling Stone
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.
But in a series of scientific epiphanies beginning in 2002, researchers using GPS have found that melting on the ice's surface can cause large sections of the ice sheet to break free of its moorings in hours, not millennia. In 2006, scientists discovered that ice was suddenly pouring into the ocean at twice the rate previously measured, spurred by a pulse of warm ocean temperatures that undercut the glaciers from below. In two separate instances, Box correctly predicted which sections of a glacier would soon break off – sections, in each case, that were many times larger than the island of Manhattan.
(Continued here.)
by: Bill McKibben
Rolling Stone
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.
But in a series of scientific epiphanies beginning in 2002, researchers using GPS have found that melting on the ice's surface can cause large sections of the ice sheet to break free of its moorings in hours, not millennia. In 2006, scientists discovered that ice was suddenly pouring into the ocean at twice the rate previously measured, spurred by a pulse of warm ocean temperatures that undercut the glaciers from below. In two separate instances, Box correctly predicted which sections of a glacier would soon break off – sections, in each case, that were many times larger than the island of Manhattan.
(Continued here.)
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