Climate change has turned Peru's glacial lake into a deadly flood timebomb
Nestled beneath the imposing white peaks of two glaciers in Peru’s Cordillera Blanca, the aquamarine Lake Palcacocha is as calm as a millpond. But despite its placid appearance it has become a deadly threat to tens of thousands people living beneath it as a result of global warming.
A handful of residents of Huaraz, the city below the lake, can recall its destructive power. In 1941 a chunk of ice broke away from the glacier in an earthquake, tumbling into the lake. The impact caused a flood wave which sent an avalanche of mud and boulders cascading down the mountain, killing about 1,800 people when it reached the city.
Today the lake is even more potentially dangerous, swollen with glacial meltwater like an almost-overflowing bathtub. A temperature rise of 0.5-0.8C between the 1970s and the 2000s has seen a third of Peru’s ice caps vanish in the last four decades.