October 26, 2021
Seven outlet glaciers of the Queulat glacier complex, Chile in 1987 and 2020 Landsat images. A=Rosselot Glacier and D=Colgante Hanging Glacier are the only ones in 1987 not terminating in a proglacial lake. The other five retreated from a proglacial lake since 1987 and Rosselot Glacier retreat has led to formation of two lakes.
Nevado Queulat, Chile is the centerpiece of the Queulat National Park in the Aysen Region. This massif is host to the Queulat glacier complex, which has a number of outlet glaciers. Rosselot Glacier is the largest glacier and it flows north draining into Lago Rosselot and then the Rio Palena. Colgante Hanging Glacier flows south and is the second largest terminating at the top of a cliff as a hanging terminus creating a spectacular waterfall. Paul and Molg (2014) observed a rapid retreat in general of 25% total area lost from glaciers in the Palena district of northern Patagonia from 1985-2011. Meier et al (2018) note a 48% reduction in glacier area in the Cerro Erasmo and Cerro Hudson region, since 1870 with half of that occurring since 1986. The 3.8 km retreat of Erasmo Glacier from 1998 to 2018 is a rate of ~200 m/year. Here we examined the changes from 1987 to 2021 of seven outlet glacier locations around the ice cap.
Seven outlet glaciers of the Queulat glacier complex in Queulat National Park in Chile in 2021 Sentinel 2 image. A=Rosselot Glacier and D=Colgante Hanging Glacier are the only ones in 1987 not terminating in a proglacial lake. The other five retreated from the proglacial lake since 1987 and Rosselot Glacier retreat has led to formation of two lakes.
In 1987 Rosselot (A) terminates against the valley where the valley turns to the east,and there is no lake at the terminus. In 1999 glacier retreat has exposed a new lake that is 900 m across. By 2015 the glacier has retreated south of a second lake that is 700 m across. In 2021 the glacier has retreated 250 m from the edge of the lake terminating at an elevation of 650 m. The total retreat from 1987-2021 has been 2100 m, ~60 m per year. This is the loss of 15% of the entire glacier length.
Seven outlet glaciers of the Queulat glacier complex, Chile in 1999 and 2015 Landsat images.
Outlet Glacier B terminates in a lake at 750 m. In 1999 the glacier has retreated to the top of a steep slope above the lake terminating at 850 m. In 2015 the glacier is terminating at 925 m and is receding up a north-south oriented valley. By 2021 the glacier has retreated 1100 m from the shore of the lake.
Outlet Glacier C terminates in a small fringing proglacial lake. By 1999 the glacier has retreated ~400 m to the base of a steeper slope, there is still ice cored moraine beyond the terminus. By 2015 a 500 m lake has formed beyond the terminus. In 2021 the glacier has retreated ~1000 m since 1987.
Colgante Hanging Glacier (D) terminates at the top of a steep cliff in 1987. The glacier reamins at the top of this cliff up to 2021, with considerable avalanching off the front into the valley below. A reconstituted glacier at the bottom of the cliff is thinning.
Outlet Glacier (E) terminated in a proglacial lake at 700 m elevation in 1987. By 1999 the glacier had a tenuous connection to the lake with a reconstituted stagnant area in contact with the lake. In 2015 the glacier no longer reaches the lake. In 2021 the terminus of the glacier is 400 m from the lake.
Outlet Glacier (F) terminated in a proglacial lake at 750 m elevation in 1987. In 1999 the glacier still connected to the lake. By 2015 the glacier had receded from this lake. In 2021 the glacier has retreated 350 m from the lake and terminates at 1000 m.
Outlet Glacier G is a stagnant debris covered glacier tongue that is in contact with a proglacial lake in 1987 and 1999. By 2015 the glacier has retreated from contact with the lake. In 2021 the glacier has retreated 600 m across an outwash plain from the lake.
Barcaza et al (2017) indicate that Colgante Hanging Glacier did not retreat from 2000-2015, while Rosselot Glacier lost 0.9 km2.