Receding Glaciers Threaten Bolivian Security
Researchers from the Manchester Metropolitan University in the U.K. published a study on October 24 that predicts potentially catastrophic flooding in the Bolivian Andes as a result of the region’s rapidly receding glaciers. Though largely tropical and flat, Bolivia is also home to a significant section of the Andes range, which contains appropriate environments for glaciers and vast high-altitude deserts. In total, Bolivia contains 20 percent of the world’s tropical glaciers. According to the study led by Dr. Simon Cook, a professor of physical geography at the university, Bolivian glaciers have reduced in size by about 43 percent in just 28 years. Such rapid deterioration has produced massive lakes and created the paradoxical threat of both flooding and water shortage.
MMU’s study measured glacial change between 1986 and 2014 using Landsat, the USGS and NASA’s Earth observation program, and examined the possible impact of this change on nearby communities. Concluding the study, the research indicated that the largest effect of the observed glacial recession would be the dangerous formation of large high-altitude lakes beneath the glaciers. According to Dr. Cook, “Glacier recession is leaving lakes that could burst and wash away villages or infrastructure downstream.”
Dr. Cook and his team identified 25 glacial lakes in the region that could pose a threat to communities or infrastructure, a phenomenon that has killed thousands in recent decades. These lakes are generally contained by rock and debris which, through rockslides or earthquakes, could be destabilized and unleash floods of up to 125,000 cubic meters per second.
Exacerbating the threat, the region already faces water scarcity issues, which will be compounded by the disappearance of glaciers. The 2.3 million residents of La Paz and El Alto, Bolivia’s largest urban centers, receive 15 percent of their water from glacial melting; this statistic increases to 30 percent in the dry season. If these glaciers disappear, irrigation, drinking water, and the survival of small communities in the area could disappear as well.