Disappearing Glaciers
The melting of glaciers worldwide is one of the starkest effects of global warming. In the Cordillera Real mountain range, part of the Andes, glaciers have lost 40 percent of their volume between 1975 and 2006. The glacier Chacaltaya, which sits approximately 20 miles from Illimani, has disappeared completely. Five years ago Chacaltaya was proudly heralded by Bolivian tour agencies as the highest ski slope in the world. Now the Bolivian Ski Club's welcome sign angles forlornly on a barren incline.
Bolivia, which is home to 20 percent of the world's tropical glaciers (glaciers that are located at high altitudes around the equator), is clearly panicked by the rapidity of glacial melt. Bolivia's tropical glaciers are especially susceptible to climactic changes: they depend on the increasingly erratic rainy season to regenerate, and their altitude compounds the effects of rising temperatures. Edson Ramirez, one of Bolivia's most respected glacier experts, predicted that Chacaltaya, at least, would last until 2015. Now, some scientists express doubt that any Andean tropical glaciers will exist in 30 years.
The trouble is that the tropical glaciers depend on seasonal regularity. In tropical zones south of the equator, seasons are generally divided into rainy and dry: dry is May through November (southern winter) and rainy is November through April (southern summer). During the rainy season, glaciers accumulate moisture and ice mass. This thaws during dry season, filling streams and rivers with fresh water precisely when it is most needed.
"Water Is Life."
When speaking about climate change, people in Bolivia use this refrain with reliable predictability. It is an uncomfortable, unavoidable aphorism. The glaciers are an indispensable part of the national water supply system; as much as 30 percent of the water supply for the 2 million residents of La Paz and its sister city of El Alto come from glacial melt. On a global scale, the U.S. National Snow and Ice Data Center estimates that 75 percent of the world's freshwater is stored in glaciers.
But warming temperatures mean that the glaciers are melting at a rate that outpaces their ability to accumulate mass during the rainy months. The consequence is that an important source of water is dwindling dangerously.
And Khapi isn't just struggling with a deteriorating water supply. As a community that relies on intimate knowledge of weather patterns in order to survive, erratic weather has introduced unforeseen challenges to food production. Sagrario Urgel, with Oxfam Bolivia, is particularly worried about the effect of unpredictable weather on rural communities like Khapi: "They don't have ways to anticipate things like they had before, for the times of planting and harvesting," she explains, "and all of this change in climate is causing considerable crop losses."
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