The end of the eternal snows: Integrative mapping of 100 years of glacier retreat in the Venezuelan Andes

Venezuela will soon become the first Andean country to lose all of its glaciers, as the "eternal snows" of the Sierra Nevada de Mérida (SNM) disappear. Although documentation of glacier retreat in Venezuela commenced over a century ago, an updated reconstruction at sufficient spatial resolution is warranted. Our objectives were to (a) produce detailed multitemporal maps of glacier cover in the SNM since 1952 and revise historical estimates for 1910 and (b) document changes in cover and rates of glacier retreat of the last Venezuelan glacier at Humboldt Peak. We integrated multiple information sources, including topographic/geomorphic evidence, high-resolution aerial photographs, satellite images, historical maps, panoramic photos, and field observations. We present 1:5,000 maps of glacier cover between 1952 and 2019 and revise the maps of 1910. In Venezuela, glacial area has decreased 98 percent between 1952 and 2019 (from 2.317 km 2 to 0.046 km 2 ). Glacier retreat rates increased after 1998, with a maximum of −16.9 percent year −1 between 2016 and 2019. These new maps should provide an essential tool for biophysical, ecological, and historical studies and a key reference for promoting awareness on climate change in the tropical Andes, where glaciers are intimately linked with cultural identity.