Chile glacier in rapid retreat
Thu, Dec 8, 2011
The Jorge Montt glacier is seen in Southern Patagonia, some 1,800 km south of Santiago. T
he Jorge Montt glacier in southern Chile is melting at a rate of a kilometer (0.6 miles) per year, making it one of the world's most visible milestones of global warming, according to researchers. (AFP Photo/)
The Jorge Montt glacier is seen in Southern Patagonia, some 1,800 km south of Santiago. …
Chile's Center for Scientific Studies (CECs) said Wednesday that several glaciers in the country's south have shrunk because of global warming but that the 454-square-kilometer Jorge Montt is one of those shrinking the fastest. The withering glacier is part of the 13,000-square-kilometer (5,020 square mile) Southern Ice Field, the third largest frozen landmass after Antarctica and Greenland.
During the 1990s, the glacier retreated some seven kilometers, but its rate of melting has "accelerated," releasing an increasing number of icebergs into the fjord where the glacier lay, according to Andres Rivera, of the CECs. The latest study of the glacier took place between February 2010 and January of this year, during which two stationary cameras timed to shoot four times a day took some 1,445 pictures of the glacier.
Baraer and his colleagues examined satellite views of the Cordillera Blanca glaciers and levels of water discharge, as well as how much the flow varied over time. They found that peak discharge from the glacier is over, Baraer said. That means that less water will reach the Rio Santa Valley during the June to November dry season, when rain is minimal and communities rely on meltwater to supply towns and agricultural fields. If the glaciers disappear completely, Baraer said, water discharge from the mountains during the Rio Santa dry season may shrink by another 30 percent of the current level. Dams could save up wet season precipitation in reservoirs for the dry season, Baraer said, but liquid reservoirs evaporate faster than solid ice glaciers, meaning that the lakes wouldn't be able to provide as much water as the glaciers have traditionally stored.
"Dams, of course, can be seen as a solution for some very particular projects, but we have to know that these dams will never ever replace the hydrological systems that are in place today," he said. Other South American regions in Bolivia, Chile and Ecuador may soon face similar challenges, he said. Peruvian officials expected this day to come, Baraer added, but many expected to have decades to plan for the end of peak water.
"What it means now for the population is that instead of having 10, 20, 30 years' perspective to find some solution for water use and allocation, in fact, these years do not exist," Baraer said.
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http://news.yahoo.com/chile-glacier-...171225862.html