The Andean Glacier and Water Atlas

have crossed the signifiant tipping point of peak water (Baraer et al., 2012)

Quelccaya ice cap, Peru Being situated at 13.5 degrees South latitude, Quelccaya Ice Cap in Peru is the world’s largest tropical ice cap. The ice cap has been retreating rapidly and these images captured by the Thematic Mapper on the Landsat 5 satellite show the difference in its extent over a period of 22 years – from 1988 to 2010. A good example of the shrinkage is the Qori Kalis glacier, which is located at the north-western part of the ice cap. Satellite imagery dating from 2010, shows that an especially large meltwater lake has been formed as result of glacial shrinkage. Altogether eight glacial lakes, seen in dark blue, have been formed between the first and second image and the Quelccaya Ice Cap is now smaller than 6,000 years ago. Aerial photographs indicate that from 1962 to 1970, there were a total of 722 glaciers in the Cordillera Blanca, covering an area of 723.4 km 2 (Ames et al., 1989). By the end of the 20th century this had been reduced to less than 600 km 2 (Georges, 2004). Glaciers in the Cordillera Blanca have been rapidly receding over the past few decades, though there have been brief periods of advancement (Vuille et al., 2008). Analysis of the Cordillera Blanca has found that many glaciers in the area

The second largest system, the Cordillera de Vilcanota is part of the eastern Oriental Cordillera. The Oriental Cordillera is reported to have lost half of its glacier area between the late 1970s and the early 2010s (Zubieta and Lagos, 2010; López-Moreno et al., 2014; Veettil & Souza, 2017).

Older lakes, which have a lower sediment content than more recently formed lakes, are seen in black.

Carbon dating of ancient plants further confirms that the advance of the ice cap 6,000 years ago was around 300 m over 1,600 years, whereas the current retreat is happening much faster at a pace of 300 m over 25 years (NASA, 16.09.2010; Thompson et al., 2013). Source (1988 image): Landsat-5 image courtesy of the U.S. Geological Survey. Path: 003, row: 070. Captured on September 3rd, 1988. Source (2010 image): Landsat-5 image courtesy of the U.S. Geological Survey. Path: 003, row: 070. Captured on September 16th, 2010.

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