Climate Change, Development & Aid, Energy, Environment, Global Governance, Headlines, Latin America & the Caribbean

SOUTH AMERICA: Glaciers – Going, Going…Gone?

Marcela Valente

BUENOS AIRES, Sep 6 2009 (IPS) - South America is perhaps most often associated with the Amazon jungle, the world’s largest tropical rainforest. But along its western edge, from Ecuador to southern Chile and Argentina, it also harbours huge glaciers which are rapidly melting due to global warming.

The 18,000-year-old Chacaltaya glacier in the Bolivian Andes disappeared in August. Experts had forecast that it would survive until 2015, but it melted sooner than predicted, and what used to be famed as the world’s highest ski run, 5,300 metres above sea level, is now a boulder-strewn slope with a few patches of ice near the top.

In Ecuador, an avalanche at the base of the Cayambe glacier killed three tourists and a mountain guide this year. And in May, an avalanche caused serious damage in the area of Pampa Linda, at the base of Monte Tronador (Thundering Mountain) in southern Argentina, when a glacier collapsed.

These isolated avalanches confirm the trend towards the collapse of the Andean glaciers, experts say.

“Glaciers in Ecuador, Peru and Bolivia have their days numbered,” Juan Carlos Villalonga, head of the Argentine chapter of the global environmental watchdog Greenpeace, told IPS. The ice sheets in Cuyo, in western Argentina, and the even larger ice sheets of Patagonia, shared between Argentina and Chile in the southwest of the continent, are also shrinking.

According to Greenpeace, the melting of the glaciers must be a cause for concern among the world leaders who will be meeting in Copenhagen in December for the 15th United Nations Climate Change Conference, and greater commitment is needed to curb the greenhouse gas emissions that cause global warming.

In an interview with IPS, glaciologist Ricardo Villalba of the Argentine Institute of Snow Research, Glaciology and Environmental Sciences (IANIGLA) said that the retreat of the glaciers’ enormous ice masses “is a global process which began in 1850 and has accelerated since 1970.”

However, this process “is not an even one,” he said. “In Ecuador or Bolivia, where the glaciers are smaller, they tend to collapse more quickly,” whereas in Argentina, some are shrinking at an alarming rate while others are surviving, depending on temperature and rainfall.

On average, however, glaciers in Patagonia have shrunk by between 10 and 20 percent in the last 20 years. “If this trend persists, the ice will all disappear within 60 or 70 years,” he said.

In a study updated in August, “Cambio Climático: futuro negro para los glaciares” (Climate Change: A Black Future for Glaciers), Greenpeace Argentina warns that the melting of glaciers in South America is accelerating. The report contains a reminder that the Intergovernmental Panel on Climate Change (IPCC) predicted this trend in 2007.

According to the IPCC, the average global temperature has risen by 0.74 degrees over the last 100 years, and the area permanently covered by ice and snow has shrunk. It also indicates that 11 out of the last 12 years have been the hottest since 1850, and global temperature is forecast to continue to rise this century.

“One of the effects climate change is expected to have is a massive loss of permanent ice cover on the earth’s surface, from the polar ice caps as well as from different bodies of continental ice,” the Greenpeace report says. This will have severe consequences, it stresses.

In first place, sea levels will rise, causing forced migration and the loss of coastal infrastructure. The proportion of reflecting ice on the earth’s surface will also shrink, increasing the amount of solar radiation absorbed by the earth and exacerbating global warming.

But above all, the melting of the glaciers means the loss of vast reserves of fresh water for human consumption, and for the rivers that provide hydroelectric power. These losses will particularly affect the Andes highlands in South America.

“South America has a surprising variety of glaciers along the length of the Andes mountain range, and the largest of them are found in Patagonia,” says the Greenpeace study. In Ecuador, “their disappearance is imminent,” and the significance of this is underlined by the fact that 50 percent of the water used by the population of Quito is glacier meltwater.

The report confirms the findings of a 2008 research study by the World Bank, titled “Impact of Climate Change in Latin America”, which points out that 70 percent of the world’s tropical glaciers are in the Andes mountains, in Ecuador, Peru and Bolivia.

In Peru alone, where millions of people depend on meltwater for their daily supply, 22 percent of the surface area of glaciers has been lost in little over 30 years. The Quelcaya ice cap has lost 20 percent of its volume since 1963, the study says. “It has retreated faster in the last century than in the previous 500 years,” according to Greenpeace.

“In the 1990s, the rate of retreat has risen to 30 metres a year,” Greenpeace said, referring to this glacier that supplies Lima with its water.

In Argentina, the immense ice sheets in Cuyo “are in a highly critical situation,” the report notes. Water is scarce in this part of the country: in the western province of Mendoza, for instance, only three percent of the land is oasis; the rest is desert and depends heavily on icemelt for water.

In Patagonia, some 20,000 square kilometres of glaciers are shared between Argentina and Chile. The Southern Ice Field in both countries spreads over 13,000 square kilometres, the Northern Ice Field in Chile covers 4,200 square kilometres, and the Darwin mountain range glaciers, also shared by the two countries, cover 2,500 square kilometres.

“Many of the largest glaciers in these ice fields have thinned alarmingly and retreated several kilometres,” except for two of them, the Perito Moreno glacier in Argentina and the Pío XI glacier in Chile, which are stable or even advancing, Greenpeace says.

In Villalba’s view, the fragile glacier ecosystem depends on the balance between the amount of snowfall and the temperature, which must be low, otherwise the glaciers collapse. He said that the recent retreat of the glaciers is associated mainly with the rise in temperature.

“The Upsala glacier, for instance, is retreating amazingly fast,” Villalba said. The glacier flows into Lago Argentino, in the southern province of Santa Cruz, and its contact with the lake accelerates its erosion. The same is true for the Viedma glacier, in the same province.

“As long as greenhouse gases continue to be released into the atmosphere, the ice will melt at an increasing rate, which is why we are calling for a reduction in the use of fossil fuels and the pursuit of alternative energies,” Villalba said.

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