Category: chile glacier melt

Sollipulli Volcano Glacier Recession Snow Cover Deficit

On By mspeltoIn chile glacier melt, chile glacier retreat

Landsat images of Sollipulli from 1986 and 2022. Point A-D are locations where the glacier spilled out of the caldera in 1986, but no longer does so in 2022.

Nevados de Sollipulli is a volcano, is in the central Andes of Chile near the border with Argentina in Parque Nacional Villarica, Chile. The 4 km wide summit caldera at ~2100 m is filled by a glacier. The volcano is dormant last producing lava flows 700 years ago and last erupting 2900 years ago (NASA, 2017). Reinthaler et al (2019) identified a 27% decline in glacier area from 1986-2015 on 59 volcanoes in the Andes. The study included Sollipulli where the area declined from 16.2 km2 in 1986, 20 12.5 km2 in 1999 and 11.1 km2 in 2015 (Reinthaler et al 2019). Here we examine Landsat imagery illustrating the recession from 1986-2022 and the loss of all snowcover for most of the summer of 2022. The summer of 2022 led to early summer loss of most/all the snowpack on Central Andes glaciers from 30-40 S. (Pelto, 2022)

In 1986 a Landsat 5 image illustrates that the glacier not only fills but overflows the caldera at Points A-D, with Point A and B feeding significant glacier area. The glacier is also almost completely snowcovered in late February. In 2003 the glacier is still spilling over at Point A, and is almost entirely snowcovered in mid-February. On January 8, 2022 the glacier is already 95% free of snowcover with some snow patches on the NW margin. By January 24 the glacier is 99% snow free and remains snow free through mid-March in a Landsat and Sentinel image from 3-13 and 3-16 respectively. There is a small patch of relict glacier ice near Point B, while the former glacier at Point A has disappeared. The annual layering preserved in the glacier ice as seen in the Landsat Band 5 image will continue to evolve as the glacier thins.  The dirty nature of this ice enhances solar radiation melting, particularly compared to snowcover.  Two months of exposure at the 2100 m elevation ice cap will have led to several meters of ice loss. The extent of the glacier has declined to 10.2 km2 in March 2022 a 37% decline since 1986.

Landsat images indicating the near complete snowcover in Landsat 7 image from 2003 and the loss of all snowcover that continued from January until at least March 13 2022. Note the annual layers preserved in the glacier ice now exposed at the surface.

Sollipulli Glacier in early January with only a fringing area of snowpack along the northwest margin. Sixty-four days later the glacier is still bare of snowpack.

Central Andean Glaciers Laid Bare for Last Half of Summer 2022

On By mspeltoIn argentina glacier retreat, chile glacier melt

Volcan Overo in Sentinel image continues to fragment with no retained snowcover this summer, and bedrock expansion at Point A.

For an alpine glacier to survive it must remain mostly snowcovered throughout the year, even at the end of the summer. This is one reason for the majesty of glaciated mountains, they shine brightly even in summer.  This year in the Central Andes of Argentina and Chile I have chronicled the near total loss of snowpack in January due to early summer warmth, leading to dirty/dark glaciers.  This is a similar story to what we saw in the Pacific Northwest last summer. Here is an update at the end of the summer using Sentinel imagery to highlight that these glaciers have remained largely bare for two months. The darker surfaces of the glacier melt faster leading to more rapid area and volume loss.  This includes fragmentation and rapid expansion of bedrock areas amidst the glacier. Earlier observations indicate this is a regional issue this summer with snowpack lost from Bajo del Plomo Glacier,  Cortaderal Glacier, Palomo Glacier, Volcan Overo Glaciers, Volcan San Jose Glaciers , Cobre Glacier and Olivares Beta and Gamma Glaciers across the Central Andes of Chile and Argentina

Cortaderal Glacier in Sentinel image with no retained snowcover this summer, and bedrock expansion at Point A.

Volcan San Jose Glaciers in Sentinel image continues to fragment with ~5% retained snowcover this summer, and bedrock expansion at Point A.

Las Vacas Glaciers in Sentinel image continues to fragment with no retained snowcover this summer, and bedrock expansion at Point A.

Olivares Beta and Gamma Glacier  in Sentinel image with no retained snowcover this summer, retreating away from proglacial lakes and bedrock expansion at Point A.

Bajo del Plomo Glacier in Sentinel image with no retained snowcover this summer, and rapid bedrock expansion at Point A.

Palomo Glacier in Sentinel image with no retained snowcover this summer, and bedrock expansion at Point A.

Volcan Peteroa Glacier in Sentinel image continues to fragment with ~2% retained snowcover this summer, and bedrock expansion at Point A.

Volcan San Jose, Central Andes Glacier Decline and Snowcover Loss in 2022.

On By mspeltoIn argentina glacier retreat, chile glacier melt

Volcan San Jose, Chile/Argentina Glacier change in Landsat 5-7-9 images from 1991, 2001 and 2022. Red arrows indicate the 1991 terminus location of three glaciers draining from the summit region, including Nieves Negras Glacier (NN). Point A-D are locations of expanding bedrock amidst the glacier.  Snowpack very limited in 2022.

Volcan San Jose is a 5850 m glacier draped volcano that straddles the Argentina-Chile border. Here we focus on the glaciers on its souther flank including the Nieves Negras Glacier. Nieves Negras drains into Rio Volcan a tributary of Rio Maipo, while the Argentina terminating glaciers drain into Rio Salinillas.  Ayala et al (2020)  examined glacier change from 1955–2016 in the Rio Maipo Basin and found a decreasing glacier mass balance trend and that glacier volume decreased by 20%. 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. Here we examine glacier changes from 1991 to 2022 with Landsat imagery and the low snowpack conditions of 2022 with Landsat and Sentinel images.

In 1991 Nieves Negras and the Rio Salinillas headwater glaciers terminated between 3100 and 3200 m.  The snowline is at 4500 m, and there is insignificant bedrock exposed at Point B and C.  By 2001 limited retreat had occurred, while bedrock exposure is apparent at Point B. The snowline is at 4600 m in 2001. In February of 2022, the glacier has retained less than 10% snowcover, with the snowline at 5200 m. The surface is notably dirty, which has enhanced melting during this summer.  Bedrock area at Point A is now 0.25 km2. Bedrock exposed at Point B has now generated two medial moraines. The bedrock exposed at Point C now has an area of 0.1 km2. At Point D there is nearly continuous bedrock extending along the ridge that marks the International boundary and the east margin of Nieves Negras. Glacier retreat of Nieves Negras is 1.7 km, there is stagnant ice below the current terminus. The debris cover obscures the actual terminus of the glacier at the headwaters of Rio Salinillas. While the northern terminus location indicates a retreat of 900 m.

The lack of snowcover matches that seen in other glacier of the Central Andes in summer 2022 such as ate the runoff into the Rio Plomo  Earlier observations indicate this is a regional issue this summer with snowpack lost from Bajo del Plomo Glacier,  Cortaderal Glacier, Palomo Glacier, Volcan Overo Glacier and Olivares Beta and Gamma Glaciers across the Central Andes of Chile and Argentina

Volcan San Jose glaciers in Feb. 17, 2022 Sentinel image. This highlights just how dirty the ice surface is and how limited the retained snowcover is.

Palomo Glacier, Chile Snow Cover Loss in 2022 and Accelerating Retreat

On By mspeltoIn chile glacier melt, chile glacier retreat, Chile glaciers and hydropower

Palomo Glacier, Chile in Landsat 5, 8 and 9 images illustrating retreat from 1987 position, red arrow, and expansion of bare rock areas amidst the glacier at Point A,B and C. Note lack of retained snowcover in 2022.

Palomo Glacier is a large valley glacier in Central Andes of Chile. Adjacent to the Cortaderal Glacier and Universidad Glacier, it flows east from Volcan Paloma (4860 m)  and drains into the Rio Cortaderal. Rio Cortaderal is in the Cachapoal River watershed that supplies two Pacific Hydro projects; a 110 MW run of river project at Chacayes and the 78 MW Coya run of river project a short distance downstream. The glacier is an important water resource from December-March. Bravo et al (2017) quantified this resource for nearby Universidad Glacier that supplied 10-13% of all runoff to the Tinguirica Basin during the melt season. La Quesne et al (2009) reported that Palomo Glacier retreated 1160 m from 1955-1978 and advaned ~50 m from 450 m 1987-2007. They reported that Palomo Glacier had an equilibrium balance durng the 1987-2000 period, which drove the lack of retreat. Here we examine the changes of this glacier from 1987-2022 using Landsat 5, 7, 8 and 9 images, and the unusually high snow lines during the winter of  2022 due largely to a January heat wave (Washington Post, 2022). This is the first post using Landsat 9, that extends this invaluable data record.

 

In 1987 Palomo Glacier terminus had been in slight advance over the previous decade. The area of bare rock at Point A was 0.25 km2. At Point B and C limited exposed rock was evident on two rock ribs.  The snowline is below Point A at 3300 m. By 2002 there is minor retreat and the area of exposed rock at Point A has expanded, with the snowline at 3600 m. By 2015 the terminus has retreated 700 m to the north end of steep slope on the east margin of the glacier. The exposed bedrock area at Point A is now 1 km2. the snowline is at 3800 m.  By mid-January 2022 the glacier has only ~10% snowcover remaining, mostly above 4000 m. Retreat since 1987 is now ~1200 m. The bedrock area at Point A is 1.5 km2. Point B is expanding ridge of bedrock and the rib or rock at Point C now separates the glacier from flow on the south facing slope east of Point C.

By February 8, 2022 with six weeks left in the melt season there is no evident retained snowpack. This will accelerate both retreat, thinning and area loss of this glacier.  This story is playing out at glaciers across the region such at Olivares Glacier, Chile,  Cortaderal Glacier, Chile and Volcan Overo, Argentina

Palomo Glacier, Chile in Landsat 7 and 9 images illustrating retreat from 1987 position, red arrow, and expansion of bare rock areas amidst the glacier at Point A,B and C.

Olivares Beta and Gamma Glaciers, Chile Bare of Snowcover in 2022

On By mspeltoIn chile glacier melt, chile glacier retreat, Chile glaciers and hydropower

Olivares Beta (B) and Olivares Gamma (G) Glacier in Sentinel image from 1-23-2022, illustrating the lack of retained snowcover with 8 weeks left in the melt season. The yellow arrow marks proglacial lakes below each glacier. The red arrow an area of emerging bedrock on the upper Beta, X marks a location where the glaciers were joined in 1986 and now have separated. 

Olivares Beta and Olivares Gamma Glacier are adjacent glaciers 50 km NE of Santiago Chile in the central Andes of Chile. The glaciers are at the headwaters of the Olivares River, which drains into the Coloardo River. The Alfalfal Hydropower Planton the Colorado River is a 178 MW run of river plant completed in 1991 and owned by AES Andes. Malmros et al (2016) identified the retreat and area change of te Olivares glaciers for the 1955-2013 period. They noted a retreat of 979 m from 1955-1994 on Olivares Beta and 753 m on Olivares Gamma Glacier. The identified area loss from 1955-2013 was 21% on Olivares Beta and 34% Olivares Gamma.  Dussaillant et al (2019) identified a 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. Here we examine Landsat imagery from 1986-2020 and Sentinel Imagery from 2020-2022 to identify changes in area and snowcover.  The lack of retained snowcover indicates mass balance losses which will drive further retreat.

Olivares Beta (B) and Olivares Gamma (G) Glacier in Landsat images from 1986, 1993, 2015 and 2020. The yellow arrow marks the terminus location in 1993 of both glaciers, the red arrow an area of emerging bedrock on the upper Beta, X marks a location where the glaciers were joined in 1986 and now have separated. 

In  1986 and 1993 both glaciers terminated in small proglacial lakes, yellow arrows, and were connected adjacent to Point X.  There is no evident bedrock emerging on the upper Beta. In 1986 there is limited retained snowcover, ~10% of total area by early March. In 1993 there is 30% snowcover on the glaciers in March. By 2015 the glacier had receded from the proglacial lakes, bedrock is emerging at the red arrow on the upper Beta, and the glaciers are barely connected at Point X. Snowcover is ~10% of total area in mid-February.  In 2020 the glaciers have disconnected at Point X and there is less than ~10% retained snowcover by mid-February. The proglacial lakes are also quite brown suggesting high runoff from the dirtier/darker glacier. By January 23, 2022 both glaciers have again lost almost all snowcover with 8 weeks left in the melt season. The dirtier firn and ice at the surface melts at a faster rate than snow for the same weather conditions.  The result will be large mass balance losses in 2022 that will further lead to glacier thinning and recession. Both glaciers currently extend from ~3800 m to ~4800 m, with areas below 4600 m consistently being in the ablation zone.

The early loss of snowcover has been seen on other nearby glaciers Cortaderal Glacier, Chile and Volcan Overo, Argentina due to the unsually warm conditions in the region, particularly in the first half of January.

Olivares Beta (B) and Olivares Gamma (G) Glacier in Sentinel image from 2-18-2020 illustrating the lack of retained snowcover with 4 weeks left in the melt season. The yellow arrow marks proglacial lakes below each glacier. The red arrow an area of emerging bedrock on the upper Beta, X marks a location where the glaciers were joined in 1986 and now have separated. 

Olivares Beta and Olivares Gamm

 

Cortaderal Glacier, Chile 2022 Heat Wave Reduces Snow Cover, Retreat Continues

On By mspeltoIn chile glacier melt, chile glacier retreat, Chile glaciers and hydropower3 Comments

Cortaderal Glacier in Landsat images from 2014 and 2022. The glacier retreated 1400 m during this interval. The snowline in January 2014 is at 3750 m. On January 15, 2022 the snowline averages 4100 m with less than 15% snowcovered with 2.5 months left in the melt season. Red arrow is 2014 terminus and yellow arrow is 2022 terminus.

Cortaderal Glacier is a large valley glacier in Central Andes of Chile. Adjacent to the Universidad Glacier, it flows from Volcan Paloma (4860 m) and Nevado Penitente (4350 m) and drains into the Rio Cortaderal. Rio Cortaderal joins the Cachapoal River, that supplies two Pacific Hydro projects; a 110 MW run of river project at Chacayes and the 78 MW Coya run of river project a short distance downstream. The glacier is an important water resource from December-March. Bravo et al (2017) noted for Universidad Glacier that it supplied 10-13% of all runoff to the Tinguirica Basin during the melt season. La Quesne et al (2009) reported that Cortaderal Glacier retreated 110 m from 1970-2000 and 450 m from 2000-2007. Here we examine the retreat of this glacier from 2014-2022 and the unusually high snow lines in mid-January of 2022 due to the recent January heat wave (Washington Post, 2022).

Cortaderal Glacier in Sentinel images from 2016 and 2022. Point A is the bedrock area that emerged in 2016 and was at the glacier front by 2022. Point T marks the 2016 terminus position, Point B is at 3750 m and Point C is at 4200 m. Snowline on January 22, 2016 is at 3200 m and averages 4100 m on January 13, 2022.

In February of 2014 the glacier terminated on the outwash plain at 2800 m. The snowline in mid January was at 3750 m. On January 9, 2016 the snowline was at 3200 m.  At Point A a small bedrock area has emerged from beneath the ice  1 km upglacier of the terminus. On January 16, 2017 the snowline is at 3750 m. On January 19, 2019 the snowline is at 3700 m. The bedrock exposed at Point A is no longer surrounded by ice due to expansion and glacier retreat. On December 14th the snowline is at 3700 m and the glacier is 50% snowcovered. By January 15 there is less than 15 % snowcover, and the snowline averages 4100 m, nearly at the top of the glacier. With 10 weeks left in the melt season snowcover will decline further. This is reminiscent of reduced snowcover on glaciers in the Pacific Northwest due to the summer 2021 heat wave (Pelto, 2021).

The glacier has retreated to Point A, with an average frontal recession of 1300 m from 2014-2022. This is greater than the retreat from 1990-2014 of ~800-900 m (Pelto, 2014).  The glacier now terminates at 3050 m in a region of much steeper slope that will reduce the retreat rate in the near future.

Cortaderal Glacier snow covered area change in two Landsat images one month apart. Snowcover declined from ~50% to 15%.

Cortaderal Glacier in Sentinel images from 2017 and 2019. Point A is the bedrock area that emerged in 2016 and was at the glacier front by 2022. Point T marks the 2016 terminus position, Point B is at 3750 m and Point C is at 4200 m. Snowline on January 16, 2017 is at 3750 m and averages 3700 m on January 19, 2019.

Landsat image indicating retreat from 1990-2014 of Cortaderal Glacier, red arrow 1990 position, yellow arrow 2014 position.

Oriental Glacier, Chile Retreats from Island Poised for Rapid Lake Expansion

On By mspeltoIn chile glacier melt

Oriental Glacier in 1986 and 2021 Landsat imagery illustrating retreat from the island (I) and diminishing width and flow of tributaries at P0int A and B. A marginal lake has formed at Point M as the glaciers terminus section has thinned and narrowed.

Oriental Glacier terminates in an expanding proglacial Lago Oriental at the northeastern margin of the Southern Patagonia Icefield (SPI). The glacier had terminated on an island in this lake for several decades until 2019. In this region glaciers thinned ~0.5 m/year from 2000-2012 with Oriental Glacier thinning 0.5-1.0 m/a (Falaschi et al 2017)..  Mouginot and Rignot (2014) identified a velocity peak at 1 km/year extending from the Cerro Azul (3018 m) eastward to the northward terminus bend.  Oriental Glacier had a slower retreat than most SPI  glaciers from 1870-2011 at 0.1-0.15 km/a, and the fastest rate from 2001-2011 Davies and Glasser (2012). Here we examine Landsat imagery from 1986 to 2021 to illustrate glacier changes and Sentinel imagery from 2020 and 2021 illustrating island separation and retreat acceleration.

In 1986 the glacier terminates on the island with a small proglacial outwash plain in front of the eastern tongue, marginal connection is 1.5 km long. Tributary A and B are both significant contributors to the terminus tongue. At Point M the glacier is 1.75 km wide.  The surface slope of the lower 6 km of the glacier in from 1986-2002 is ~4-5%, this is a low surface slope, suggesting this section of the glacier occupies a basin, a continuatin of the current Lago Oriental.  In 1998 there is little evident change.  By 2002 the glacier connection to the island has a similar length, but the ice is thinner than in 1986. In 2015, tributary A and B are narrower, contributing less ice to the terminus region. The connection to the island is reduced to ~1 km, while the proglacial outwash plain is still similar in size. In January of 2019 the connection to the island is almost gone and the proglacial outwash plain is significantly reduced. The marginal lake is ~0.05 km2. By February of 2020 the connection to the island has been lost and the marginal lake has expanded to 0.1 km2. In 2021 the glacier has retreated 150 m from the island and a rift has formed that will lead to a signficant calving event ~0.125 km2, probably this summer. The marginal lake has expanded to 0.2 km2 . Tributary B has essentially separated from the main glacier in 2021.

Calluqueo Glacier retreat and Lucia Glacier retreat have been significantly larger; however, Oriental Glacier is poised for a rapid retreat and lake expansion. The lake basin likely extends at least 5 km from the present terminus. At that point Lago Oriental would be 9 km long.

Oriental Glacier terminus reach in 2019, 2020 and 2021 Sentinel 2 imagery illustrating retreat from the island (I) and expansion of the marginal lake at Point M. Note tributary B has essentially disconnected in 2021. A rift is forming at yellow arrow, poised for a calving event this summer.

Oriental Glacier in 2002 and 2015 Landsat imagery illustrating connection remaining to the island (I). A small marginal lake has formed at Point M as the glaciers terminus section has thinned and narrowed.

Oriental Glacier in 1998  Landsat image and topographic map of area. Elevation contours indicates low slope of termius reach from 600 m to terminus. Blue arrows indicate glacier flow. 

 

Steffen Glacier, Chile Drainage of Laguna de Los Tempanos

On By mspeltoIn chile glacier melt, chile glacier retreat

Laguna de los Tempanos full on February 9, 2021 and drained on December 6, 2021 in Sentinel 2 images. Point A marks the western margin when full. Point C marks the western margin when drained. 

Steffen Glacier is the south flowing glacier from the 4000 km2 Northern Patagonia Icefield (NPI). Several key research papers have reported on the spectacular retreat of this glacier in recent years.  Glasser et al (2016) reported that Steffen Glacier proglacial lake area expanded from  12.1 km2 to 20.6 km2 from 1987 to 2015, due tin part to a 100 m snowline rise. noted to have risen ~100 m.  Dussaillant et al (2018) determined the annual mass loss of NPI at ~-1 m/year for the 2000-2012 period, with Steffen Glacier at -1.2-1.6 m/year. Millan et al (2019) indicate the area of tributary glacier convergence near the northwest terminus and above the glacier is 700 m thick, and that the glacier has been retreating along an area where the glacier bed is below sea level, though the terminus now is close to sea level. Steffen Glacier retreat from 1987-2019 was 4.4 km, ~137 m/year (Pelto, 2019). Aniya et al (2020) reported on 19 glacier drainage events from 1974-2020, with most occurring in late summer or early Fall. They noted the largest in 2016 and 2017 were the first to expose much of the lake bottom.

There are two large ice dammed proglacial lakes on the west side of the glacier.  Laguna de Los Tempanos is the southern one 6 km upglacier of the current terminus and 11 km upglacier of the 1987 terminus position. Here we utilize Landsat and Sentinel imagery to examine the evolution of the lake from 1987-2021, Including the 2021 drainage event.

Laguna de los Tempanos in Landsat images from 1987, 1999, 2012 and 2019. Yellow arrow is western extent of the lake in 1987 and 1999, while Point A is the western extent in 2012 and 2019.

In 1987 the area of the lake is 5.2 km2 extending west past point A to the yellow arrow. In 1999 the water level is lower leading to a peninsula developing at Point A, with a lake area of 5.0 km2.  By 2012 the water level had dropped further and the west margin of the lake was now at Point A and the lake area was 4.8 km2.  The filled size remained unchanged for most of the 2012-2021 period, though there was large drainage events in 2016 and 2017 the lake rapidly refilled.

I

On November 17, 2016 the lake is full, but it is drained on April 16, 2017 with evident icebergs on the bottom, the drainage event occurred on March 30/31 2017 (Aniya et al 2020) . 

By January 21, 2018 the lake is again full and is full again on December 7, 2018 in Sentinel 2 images.

The lake is full on March 27, 2019 and on Feb. 20, 2020 in Sentinel 2 images.

 

On March 31, 2021 the lake is still full, by November 16, the lake area had declined from 4.5 km2 to 1.9 km2, in Sentinel 2 images.

The drainage event appears to have been in the early spring as the lake is full on May 20, 2021 at the start of the winter season and at the end of the winter season on August 8, 2021 in Sentinel 2 images. The lake remained largely filled on Sept. 7, 2021, but had drained by Oct. 7, 2021.

By October 7, 2021 the  lake had drained and two months later the lake is still not filling.  As Steffen Glacier thins, its ability to impound this lake has diminished from 1987 to 1999, from 1999 to 2012 it diminished again.   Now we may have another evolution in this process, with the more complete drainage starting in 2016 and now in 2021 the first event where refilling is not progressing.

Bernardo Glacier, Chile Retreat Yields 15 km2 Lake Expansion 1986-2021

On By mspeltoIn chile glacier melt, chile glacier retreat1 Comment

Bernardo Glacier in Landsat images from 1986 and 2021 illustrating retreat at the southern (S), middle (M) and northern (N) terminus respectively. Red arrows are 1986 terminus locations, yellow arrows are 2021 terminus locations. Separation from Tempano occurs at S, while lake expansion occurs at M and N.

Bernardo Glacier is an outlet glacier on the west side of the Southern Patagonia Icefield (SPI) that  currently ends in an expanding proglacial lake system, with three primary termini.  Here we examine changes from 1986 to 2021 using Landsat images. Davies and Glasser (2012) indicate that over the last century the most rapid retreat was from 2000 to 2011. Willis et a (2012)  note a thinning rate of 3.4 meters per year during this period of the Bernardo Glacier region, which drives the retreat. Mouginot and Rignot (2014) illustrate that velocity remains above 200 m/year from the terminus to the accumulation zone on Bernardo Glacier. Eñaut Izagirre visited the glacier in 2019 and provided images of the middle terminus of Bernardo Glacier, below.

Bernardo Glacier in Landsat images from 1998 and 2020 illustrating retreat at the southern (S), middle (M) and northern (N) terminus respectively. Red arrows are 1986 terminus locations, yellow arrows are 2021 terminus locations. Separation from Tempano occurs at S, while lake expansion occurs at M and N.

In 1986 Bernardo the southern terminus of the glacier was in tenuous contact with Tempano Glacier.  The middle terminus primarily ended on an outwash plain with a fringing proglacial lake developing.  The northern terminus had retreated a short distance south from a peninsula that had acted as a pinning point.  By 1998 the northern terminus had retreated into the wider,deeper portion of the lake basin that was now filled with icebergs. The middle terminus remained grounded on an outwash plain, with proglacial lake expansion at the NW corner of the terminus.  A small lake has developed completely separating Bernardo Glacier and Tempano Glacier. By 2003 the northern terminus had retreated 2 km from 1986, the middle terminus 1.5 km and the southern terminus 1.2 km in an expanding proglacial lake.  By 2015 the lake between Tempano and Bernardo Glacier had drained, but a fringing proglacial lake at the margin of Bernardo Glacier was forming.  In 2015 the northern terminus had retreated 3.5 km since 1986, the middle terminus 2.5 km and the southern terminus 2.75 km.   From 2015 to 2020 the change of the southern terminus was limited to a limited expansion of the fringing proglacial lake, a limited retreat of the the northern terminus, while the middle terminus had retreated significantly into a wider portion of the lake basin.  By 2021 the southern terminus had retreated 3 km since 1986, the middle terminus 4.6 km and the norther terminus 4.1 km.  This led to a 8.7 km2 lake expansion at the middle terminus and a 7.8 km2 lake expansion at the northern terminus. Gourlet et al (2016) identify Bernardo Glacier as having thinner ice than other large outlet glaciers such Jorge Montt or O’Higgins, which helps lead to rapid terminus change. The retreat is similar to the extensive retreat observed at Dickson Glacier and Upsala Glacier.

Southern Andean huemel an endemic deer on the foreland beyond Bernardo Glacier (photograph from Eñaut Izagirre).

Middle terminus of Bernardo Glacier in 2019 taken by Eñaut Izagirre who considers this a condor-view.

Bernardo Glacier in Landsat images from 2003 and 2015 illustrating retreat at the southern (S), middle (M) and northern (N) terminus respectively. Lake expansion and then drainage occurs at S. Red arrows are 1986 terminus locations, yellow arrows are 2021 terminus locations.

Queulat Glacer Complex, Chile Recession 1987-2021

On By mspeltoIn chile glacier melt, chile glacier retreat

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.

HPN4 Glacier, Chile New Lake Forms and Drains in 2021

On By mspeltoIn chile glacier melt, chile glacier retreat

Glacier dammed lake formation at HPN4 Glacier, Chile between Landsat images of Feb. 2020 and Feb. 2021, yellow arrows indicating new calving fronts on either end of lake. 

HPN4 Glacier drains the southern side of NPI just east of Steffen Glacier. The terminus retreated little from 1987-2015, see below (Pelto, 2015 and 2017). The main change is in the eastern tributary 1-2 km north of the terminus. In 1987 there were five separate feeder ice tongues descending from the ice cap into this valley.  By 2015 there was just one.  Further this tongue has narrow and downwasted and a new lake is developing.

In February 2020 the lake has still not formed, note yellow arrows. In February 2021 the lake has formed between the yellow arrows and is 2 km long and has an area of 1.1 km2. The drainage of this lake was reported by on Claudio Bravo Lechuga comparing PlanetLab images from 2-15-2021 and 2-23-2021.

HPN4 and glacier dammed lake in Sentinel2 Image from 2-9-2021.

HPN4 Glacier in 1987 and 2015 Landsat imagery.  Red arrow indicates 1987 terminus, yellow arrow 2015 terminus, purple arrows indicate medial moraines

The below is from Pelto (2015 and 2017). In 1987  and 2004 there were five contributing glacier tongues to the downwasting tributary, see below. It is like a bathtub being filled with five taps at once. The purple arrow indicates a medial moraine at the mouth of the valley, signaling the lack of current contribution of the downwasting tributary to HPN4 Glacier.  The medial moraine has shifted east indicating that the main HPN4 Glacier is now flowing into the valley instead of the downwasting tributary being a contributing tributary to HPN4.  By 2015 there is only one contributing glacier tongue to the downwasting tributary, only one tap for this draining bathtub, the other four contributing tongues have retreated from contact with the downwasting tributary.  The medial moraine has spread eastward and some fringing proglacial/subglacial lakes are evident  A closeup 2013 Digital Globe image indicates both fringing ponds-blue arrows, rifts caused by varying flotation-green arrows and expanding supraglacial ponds, red arrows.  The rifts are a sign of instability and typically lead to break up of this portion of the terminus. The downwasting tributary continues to demise faster than HPN4 Glacier, which crosses the valley mouth, hence it is likely that a glacier dammed lake will form and that HPN4 Glacier will continue to flow further east up this valley.

Schaefer et al (2013) discuss the HPN4 Glacier because the main terminus has changed little given its modeled mass balance, and the modeled mass balance to the east appears too negative, which they suggest indicates wind redistribution from the HPN4 to the Pared Sud Glacier just east. Davies and Glasser, (2012)  identify this region of the icefield as retreating faster from 2001-2011 than during any measured period since 1870.  This has led to the formation and expansion of many lakes in the basin Loriaux and Cassasa (2013) . Glasser et al (2016) observed that proglacial and ice-proximal lakes of NPI increased from 112 to 198 km2. The largest expansion this century being at San Quintin Glacier at ~24 square kilometers.

hpn-4 2004

2004 Landsat image showing five contributing tributaries

hpn4-ge

Google Earth image 2013

Tres Puntas Glacier, Chile Loses 50% of its Length this Century

On By mspeltoIn chile glacier melt, chile glacier retreat

Tres Puntas Glacier, Chile in 1999 and 2021 Landsat imagery. Red arrow is 1999 terminus location, yellow arrow the 2021 location, Point A is where tributaries joined in 1999 and Point B is where an adjacent glacier drains west.

Tres Puntas Glacier flow south from Cerro Tres Puntas draining south into Lago O’Higgins in Patagonia. The icefield is east of the Patagonia icefields where Davies and Glasser (2012) noted the nearby (50 km se) Lago Del Desierto glaciers lost 0.6% of its glacier area from 2001-2011, a much higher rate than from 1986-2000.

In 1999 the glacier is 5.6 km long with two significant tributaries joining at 850 m (Point A) before terminating in a proglacial lake at 600 m. The glacier shares a broad divide near Point B with glacier flowing west. In 2002 the snowline is at 1100 m, the terminus is still terminating in the proglacial lake. By 2020 the glacier tributaries have separated and now terminates at 900 m, above Point A. At Point B there is a separation between this glacier and the glacier draining west. By mid-February of 2021 the west tributary has retreated 2.8 km, 50% of its 1999 length, while the eastern tributary has retreated 2.4 km of its 5.0 km length. The snowline in mid-February of 2020 and 2021 has been at 1200 m, above the median glacier elevation. Further retreat of the eastern arm should lead to an additional alpine lake forming.

The retreat of this glacier is more extensive than that of the nearby Sierra Sangra glaciers,  Argentina.  The retreat from an expanding proglacial lake also has played out at Cordillera Lago General Carrera Icefield, Chile

Tres Puntas Glacier, Chile in 2002 and 2020 Landsat imagery. Red arrow is 1999 terminus location, yellow arrow the 2021 location, Point A is where tributaries joined in 1999 and Point B is where an adjacent glacier drains west.