March 17, 2022
Cobre Glacier, Argentina in false color Sentinel 2 images from Jnauary 13, 2022 and March 16, 2022. Note the expansion of bedrock area amidst the glacier at Point A, glacier fragmenting at Point B and Point C.
Cobre Glacier drains east from Cerro Orejas a 3949 m peak on the Chile-Argentina border and discharges into the Rio Tordillo. The summer of 2022 has been a difficult season for glaciers in the Central Andes of Chile and Argentina as has been observed with early snowpack loss on Bajo del Plomo Glacier, Cortaderal Glacier, Palomo Glacier, Volcan Overo Glacier and Olivares Beta and Gamma Glaciers. Here we can utilize Sentinel 2 satellite imagery to observe the retreat from 2016-2022 and the area losses apparent during the summer of 2022.
In March 2016 Cobre Glacier terminated on the northern shore of a proglacial lake at ~3000m. By March 2022 the glacier had retreated 700 m from the lake in just six years. During this period thinning of the glacier had narrowed the connections at Point A-C, while a new lake basin is evolving at Point D. Early summer warmth led to a rapid loss of snowpack on Cobre Glacier in 2022. By January 13, 2022 ~5% of the glacier had small pockets of snowcover above 3800 m. Bare ice glacier surfaces melt more rapidly than snow covered surfaces. After over two months of bare ice ablation the small areas of emergent bedrock on January 13, near Point A have enlarged and merged with the margin of the glacier by March 16. At Point B a small ice cap is separating from the main glacier. At Point C a narrow tongue of ice that had connected the main glacier to a small terminus segment has been severed. At Point D margin retreat is leading to expansion of the proglacial lake along the margin of the glacier. In just two summer months the impact of a single warm summer is evident on Cobre Glacier. It is also evident that with no persistent accumulation zone this glacier cannot survive current climate( Pelto, 2010). Dussaillant et al (2019) identified slower mass loss -0.28 m/year in this region from 2000-2018, than further south in the Patagonia Andes or north in the Tropical Andes. In 2022 the Central Andes are experiencing a rapid loss.
Cobre Glacier in Sentinel 2 images from March 2016 and March 2022. Illustrating retreat from 2016 terminus (red arrow) to 2022 terminus (yellow arrow). Fragmentation of the glacier underway at Point A-C is evident. A new evolving lake is at Point D.