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Tuesday, June 23, 2009

Patagonian glaciers of Chile and Argentina are losing ice mass at higher altitudes at much faster rates

CHILEAN GLACIERS MELTING AT UNPRECEDENTED RATES




by Natalie Muller, Santiago Times, 23 June 2009

NASA Scientists Reveal Patagonia Glaciers Are Losing Ice Mass In Higher Zones

The latest research expedition to the Southern Patagonia Ice Field revealed that alpine glaciers in the Chilean and Argentine Andes are disappearing at much faster rates than previously anticipated by the scientific community.
glaciar_grey_chile
Grey's Glacier meets Lake Grey in Patagonia's Torres del Paine National Park.
Photo courtesy of Flickr, bigeoino
A preliminary analysis by a team of scientists from NASA and Chile’s Valdivia-based Center of Scientific Studies (CECS), which commenced an expedition to the Ice Field in October 2008, sheds light on the alarming speed at which the glaciers are depleting.

The scientists discovered that the masses of ice in the Patagonia are melting in larger proportions and in much higher alpine zones than in any other part of the world, including Alaska and the Himalayas. Glacier ice accounts for around 75% of the world’s fresh water.

“The loss of ice mass in the higher zones is the really new phenomenon,” said Gino Casassa, a CECS glaciologist. “At least this is what we are seeing with the preliminary results which we have just received.”

Until recently, it was believed that glacial loss occurred from lower areas, and that snowfall on the higher sections of glaciers would compensate for loss of ice at lower altitudes.

“One hypothesis we put forward was that there could be a positive balance of ice in the high zones because of higher rates of snowfall in these areas,” said Casassa.

But with ice thinning high up and down low, too, loss in glacial mass in Patagonia is likely to be much greater than what has previously been calculated by scientists.

The new findings are also curious because they contradict some former studies.

For example, a previous study found that the Chilean glaciers Trinidad and Pio XI (the biggest glacier in the southern hemisphere outside of Antarctica) had advanced instead of receded, while the Perito Moreno glacier in the Los Glaciares National Park in southern Argentina had maintained a volume balance.

Between 1944 and 1986 glacial ice in the Southern Patagonia Ice Field was recorded as retreating at an average of 57 meters per year.

Most of Chile’s 3,500 identified glaciers can be found in the Patagonia Region. And most have experienced significant losses in volume and surface area due to climate change and are in danger of disappearing altogether.

“This loss contributes significantly to sea levels,” noted Casassa. “Between 1995 and 2000, Patagonian glaciers made up 9% of the total glacier contribution to sea levels.”

The shrinking mass of the Patagonian glaciers, especially the accelerated melting of the sections of glaciers in lower altitudes, was established by 1996 satellite studies and the more recent work of Japanese scientists and Eric Rognot from NASA in 2003.

The Southern Patagonia Ice Field has the third largest concentration of continental ice, after Antarctica and Greenland. Many of the Patagonia glaciers are protected under different National Parks, including Torres del Paine and Bernardo O’Higgins in Chile, and Los Glaciares in Argentina.

The higher temperatures associated with glacier meltdowns and climate change are largely caused by CO2 or “greenhouse gas” emissions. Chile’s failure to develop a sensible renewable energy policy has resulted in a green light to highly-polluting coal and diesel fuel energy production.

State authorities confirm that the nation’s CO2 emissions will quadruple in the next 20 years if no mitigating actions are taken.

SOURCE: EL MERCURIO
By Natalie Muller ( editor@santiagotimes.clThis e-mail address is being protected from spam bots, you need JavaScript enabled to view it )

Link to article: http://www.santiagotimes.cl/santiagotimes/index.php/2009062216532/news/environmental-news/chilean-glaciers-melting-at-unprecedented-rates.html

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