1975-2018: 43 Years of Glacial Retreat in the Incachiriasca Glacier (Nevado Salcantay, Vilcabamba Range, Peru)

Glaciers are sensitive indicators of climate change, especially small sized tropical glaciers, since they are the most susceptible to any minimal variation of climatic conditions. This study focuses on the analysis of the shrinkage of the Incachiriasca II glacier (72 degrees 32'W, 13 degrees 21'S; similar to 4950 m) from 1975 to 2018. The first reference of the glacier's delimitation is the annual topographies by Peruvian researchers between 2007 and 2018. This time sequence has been extended to 1975 by analysing 28 LANDSAT images. Our results show a loss of 51.4% (-0.271 km(2)) of the glacier's total area: from 0.528 km(2) (1975) to 0.257 km(2) (2018), equivalent to -0.0063 km(2)yr(-1) (1.2% yr(-1)). According to the observed trend, the annual rate of decline has increased considerably, especially since 2010, from 1% in 2001-2010 to 3% in 2010-2018.