From Greenland to Andes, signs mount of climate shift

A new report in the journal Science finds that the contraction of Greenland's ice sheet has accelerated over the past years. Using computer modeling and satellite data, the team concluded that the ice mass shrank by 273 billion tons a year during the warm summers from 2006 to 2008—a roughly a 70% increase over the average 166 billion tons a year from 2000 to 2008. "It is clear from these results that mass loss from Greenland has been accelerating since the late 1990s and the underlying causes suggest this trend is likely to continue in the near future," said researcher Jonathan Bamber, one of the authors of the study. The Greenland ice sheet is the second largest in the world after Antarctica, and could increase sea level by 7 meters were it to completely melt. (Planet Earth Online, AFP, Nov. 13)

Meanwhile in South America, water levels on the world's highest navigable lake have dropped 81 cm (2.6 ft) in just seven months since April this year, according to the Lake Titicaca Authority (ALT), jointly overseen by the governments of Peru and Bolivia. The lake is now at its lowest level since 1949 according to the findings, released at a press conference in La Paz.

The lake's water level rises and falls frequently, the sharper fluctuations caused by heavy rains and droughts in years affected by El Niño weather phenomenon. Although El Niño is expected to be mild to moderate this year, November through January, it will likely mean much less rainfall for the southern Andes.

Over the past four years, the seasonal rainfall and the flow into Lake Titicaca from feeder rivers have not been sufficient to compensate for the loss of water from evaporation and the discharge of water from the lake into the Rio Desaguadero. The result is that every year since 2005, the water levels have not recovered the previous year's level. The Titicaca Authority says 95% of the lake's inflow is now evaporating. About 2.6 million people depend on the lake for their sustenance.

Felix Trujillo, chief of Bolivia's National Meterological and Hydrological Service, noted that the area's rainy season has been reduced from six to three months in recent years. The drought has prompted water rationing in some Bolivian cities. (Peruvian Times, Nov. 13; AP, Nov. 12)

The findings come on the heels of a regional summit on the impacts of climate change in the Andes, held in Lima weeks earlier.

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Greenland going fast...

From AFP, Aug. 12:

Environmental watchdog Greenpeace said Thursday it was expecting the disintegration of the Petermann glacier in north-western Greenland, from which a massive ice island four times the size of Manhattan broke off earlier this month.

"We had been expecting since last year that unavoidable break of the edge of the glacier, which we studied closely with an international team of researchers during an expedition in July and August 2009," Mads Flarup Christensen, who heads Greenpeace in the Nordic countries, told AFP.

He said the expedition had found "breaches in the glacier" that foretold the coming disintegration.

Early on August 5, "an ice island four times the size of Manhattan was born in northern Greenland," after breaking off from Petermann, Andreas Muenchow at the University of Delaware said in a statement Friday.

He added that the last time the Arctic lost such a large chunk of ice was in 1962.

More recently, the glacier has lost smaller islands of ice, said Jason Box, of the polar research centre of the University of Ohio, who took part in Greenpeace's expedition.

Box and colleagues David Decker et Russ Benson found the Petermann glacier has in total retreated 21 kilometers (13 miles) in just 10 years.

Greenpeace's Christensen said Petermann has retreated to a "historical level" and is putting out "more icebergs, at an accelerated pace."