Warming Sign: 1600 Years of Ice in Andes Melted in 25 Years

Researchers are documenting glacier ice in the Peruvian Andes. “Rapid melting there in the modern era is uncovering plants that were locked in a deep freeze when the glacier advanced many thousands of years ago,” reports Justin Gillis for the New York Times. “Dating of those plants, using a radioactive form of carbon in the plant tissues that decays at a known rate, has given scientists an unusually precise method of determining the history of the ice sheet’s margins.” In the case of Quelccaya, “the ice cap had reached its smallest extent in nearly five millenniums”; otherwise, previous melts would have led to plant decay. The researchers can drill into glacial ice, connecting patterns with food shortages and wars like the French Revolution. Global warming is taking its toll on high latitudes and altitudes. In the short term, the melt-off adds to regional water supplies and fuels urban population growth. In the long term, the region can expect water shortages during dry seasons. – YaleGlobal