Recent mass balance changes of the Agua Negra glacier in the Desert Andes of Argentina

MASIOKAS M; CORVALÁN ERNESTO; PITTE P.; RUIZ L.; GARGANTINI H.

JOURNAL OF GLACIOLOGY

INT GLACIOL SOC

Lugar: London; Año: 2021

0022-1430

The Desert Andes, in northern Argentina and Chile, contain >4500 icemasses but only a handful are currently monitored. We analysed AguaNegra, a small mountain glacier, with remote sensing and in situmeasurements. Between 1959 and 2019 the glacier lost 23 % of its areaand the glaciological measurements for 2014-2021 show an averageannual mass balance of -0.52 m w.e a-1, with 0.80 and -1.33 m w.e. a-1mean winter and summer balance. The ELA was 5100±100 m a.s.l.,which indicates an AAR of 0.28±21. Longer term geodetic data, fromSRTM X-band and PLEIADES satellite data showed a doubling of themass loss rate, from 0.32±0.03 m w.e. a-1 in 2000-2013, to -0.66±0.06m w.e. a-1 in 2013-2019. Comparatively, the mass losses at the Jáchalriver basin (25500 km²), derived from ASTER data, were les negative, -0.11±16 m w.e a-1 for 2000-2012 and -0.17±14 m w.e. a-1 for 2012-2018. Finally, climate data shows a warming since 1979 and a decline insnow accumulation. The ongoing extreme drought affecting this regionsince 2009 is enhancing the mass loss and highlights the importance ofsustained monitoring of glaciological and hydro-meteorological variablesin this extensive arid and mountainous region.