With Speed and Violence Fred Pearce - Global Commons Institute

esults of a detailed satellite radar study of the ice sheet showing that it was
losing 180 million acre-feet more of ice every year than it was accumulating
through snowfall. That was double the estimated figure for a decade before.
And all this gives real substance to the evidence accumulating from
Greenland's glaciers, the ice sheet's outlets to the ocean.
Swiss Camp is in the upper catchment of a glacier known as Jakobshavn
Isbrae. It is Greenland's largest, flowing west from the heart of the ice sheet
for more than 400 miles into Baffin Bay. It drains 7 percent of Greenland.
Jakobshavn has for some decades been the world's most prolific producer of
icebergs. From Baffin Bay they journey south down Davis Strait; past Cape
Farewell, the southern tip of Greenland; and out into the Atlantic shipping
lanes. Jakobshavn was the likely source of the most famous iceberg of
all—the one that sank the Titanic in 1912. But it has been in overdrive since
1997, after suddenly doubling the speed of its flow to the sea. It is now also
the world's fastest moving glacier, at better than 7 miles a year.
Jason Box has installed a camera overlooking the glacier to keep track. It
takes stereo images every four hours throughout the year. As well as flowing
ever faster toward the sea, he says, the glacier is becoming thinner, and in
2003 a tongue of ice 9 miles long that used to extend from its snout into the
ocean broke off. "What is most surprising is how quickly this massive volume
of ice can respond to warming," says Box. There seems to be a direct
correlation between air temperatures in any one year and the discharge of
water from glaciers into the ocean. Long time lags, once thought to be a
near-universal attribute of ice movement, are vanishing. Jakobshavn, he
estimates, could be shedding more than 40 million acre-feet a year, an
amount of water close to the flow of the world's longest river, the Nile. Half