Snowcover loss on Cofto, Fiero and Del Humo Glacier in Sentinel images from January 13 and February 9, 2023, snowpack diminished from 45% to less than 3%.

Rio Atuel drains from the high Central Andes in Western Argentina and is a snow and glacier fed system In the headwaters region there are a series of glaciers that have been losing mass and retreating.The most negative mass balance rates from 2000–2018 in this region of Argentina were in the  Atuel basin at −0.70  m/year (Ferri et al 2020). Both minimum and annual discharge in the Rio Mendoza has diminished from 1980-2010 (Lauro et al 2019).

Here we examine the snowcover loss between January 13 and February 9, 2023 on four of these glaciers from south to north Fiero, Corto, Del Humo and La Laguna. In mid-January snowcovered 40-50% of these glaciers. After a significant heat wave from January 28-Feb. 9. the snowcover had declined to less than 3% with six weeks left in the melt season.  This is the second year in a row these glaciers have lost all snowcover. This has further concentrated light absorbing particles at the surface, decreasing albedo, and increasing glacier melt. The glaciers simply put look quite dirty.  This is a cumulative process that is enhanced by consecutive high melt years and causes rapid volume loss.  Shaw et al (2020) found a significant ongoing decline in ice albedo in these region of the Andes that is impacting their overall mass loss.  The increased frequency of heat events continues to enhance melting of Central Andean glaciers. This process is playing out this year on Sollipulli Glacier and in 2022 on many Central Andean glaciers.

Snowcover loss on La Laguna Glacier in Sentinel images from January 13 and February 9, 2023, snowpack diminished from 40% to less than 3%.

Volcan Overo is a 4619 m high Andean mountain in Argentina with a relatively low sloped broad summit region above 4000 m. The summit region is host to a glacier complex that is shrinking and fragmenting. In mid-January, 2022 the glacier has lost all of its snow cover. Volcan Overo in February 2023 the glacier complext has again lost all snowcover, which is leading to furtherfragmentation at the yellow arrows, even since 2022.

Volcan Overo in 2022 and 2023 having lost all of its snowcover. Expanding lakes at blue arrows.