Corihuasi East Glacier Retreat, Peru

On January 19, 2013January 19, 2013 By mspeltoIn Glacier Observations1 Comment

In the Cordillera Centrale of Peru a series of glaciers extends north from Pariacaca. Pariacaca is the pre-Incan god of water, appropriate name in this dry region, that is draped with glaciers and has numerous alpine lakes. On the north side of Pariacaca Mountain is the Corihuasi East Glacier. The Corihuasi Glacier has been retreating and has developed a number of holes that penetrate the glacier to its bedrock base. The retreat of this glacier is similar to that of Manon Glacier and Chuecon Glacier in this same mountain range. The glacier flows northeast beginning at 5200 meters and ending at 5100 meters. The glacier is 1.3 km long and has an area of 0.8 square kilometers in 2010. This post examines Landsat imagery from 1998, 2005, 2011 and 2012 and Google Earth imagery from 2010, shown in that order below. The red arrow in each image indicates the 1998 terminus location which ended in a lake. The yellow arrow indicates the location of a bedrock exposure amidst the glacier that will develop and enlarge. By 2005 the glacier has retreated from the lake, 110 meters from 1998 and the bedrock exposure is evident. In 2011 and 2012 the glacier has retreated 200 meters from the 1998 position and the bedrock exposure has greatly expanded. The Google Earth imagery has much better resolution. The size of the bedrock exposure is 230 meters by 100 meters. What is of greater concern for the survival of this glacier is the development of a number of holes in the glacier that reach the glacier base, at the yellow arrows. There is a clear depression extending west from the main bedrock exposure to another depression reaching the glacier bed, this will allow expansion of the main bedrock exposure from 230 m to 400 m. In each case once bedrock at a glacier base is exposed this will speed up melting of the surrounding ice and demise of this glacier. This glacier will not survive current climate because in many years such as 1998 and 2010 the glacier has lost all its snowcover indicating a glacier that does not have a persistent accumulation zone. Without a persistent accumulation a glacier cannot survive. (Pelto, 2010).

Riggs Glacier Retreat from the Sea, Alaska

On January 16, 2013 By mspeltoIn Glacier Observations5 Comments

Riggs Glacier for most of the 20th century was a tributary to the Muir Glacier in Glacier Bay Alaska. The two glaciers separated between 1960 and 1963 as noted by the USGS in their detailed research led by Bruce Molnia . The USGS chronicled the changes of this glacier from 1940 to 2004 with pictures from the same location by Bruce Molnia. The Muir and Riggs are still joined in 1950 and the Riggs Glacier is retreating out of sight into its own valley by 2004.

Dan Lawson in a 2004 National Park Service brochure noted that Riggs Glacier was about 1.2 km wide at the terminus, had a 40 to 90 feet high ice face and was 15 miles long. The terminus that had been calving into Muir Inlet for the entire 20th century became mostly terrestrial during the mid-1980,s as an outwash delta built at the southern margin. In 2004 tidewater only reached the terminus during higher tides on either side of the bedrock knob that separates the glacier into two ice tongues. Riggs Glacier has been thinning progressively over the past two decades and is expected to continue thinning and slowly receding. Ice recession has been averaging about 20 to 30 feet per year for the last 5 years. This post examines changes as seen in Landsat images from 1990 to 2011.

In 1990 the two terminus tongues are still connected at the black arrow, and a prominent knob is just being exposed by retreat of the western terminus, red arrow. The terminus still reaches tidewater on the very northern margin. There is no vegetation evident on the knob separating the ice tongues. A tributary from the east at the orange arrow just reaches the Riggs Glacier. By 1999 the termini are separated the prominent knob is now fully exposed by retreat of the western terminus and the glacier is no longer tidewater except briefly at high tide. Vegetation has become to develop on the rock knob that separates the two ice tongues. By 2009 the glacier has retreated well back from tidewater. The delta building in front of the eastern terminus has expanded into the inlet some. Vegetation has spread over most of the rock knob that separates the two ice tongues. In 2010 in a late summer images the snowline of the glacier is at 975 m. The tributary from the east at the orange arrow has retreated 1 km from the Riggs Glacier. By 2011 the western terminus has retreated 600 meters since 1990 and the eastern terminus has retreated 800 meters from the black arrow where it used to connect to the main glacier. Examination of the snowline elevation on Riggs Glacier indicates that it now typically it is typically between 950 and 1050 m. This recent increase in the snowline is similar to the increase seen on Brady Glacier. This has led to the glacier retreat and it no longer reaching the sea.

Dodge Glacier and Storm Glacier Retreat, Northern Greenland

On January 12, 2013January 12, 2013 By mspeltoIn Glacier Observations3 Comments

The Dodge and Storm Glacier are two glaciers that separate 1.5 km from the ice front around Kap Alexander (Cape Alexander) in northern Greenland. The glaciers are fed not by the main Greenland Ice Sheet, but a local ice cap. Lauge Koch (1928) documented this in his map from the expedition to the region in 1920-1923. The black arrows in the map from his expedition indicate the highest point of the ice cap and the saddle separating the Greenland Ice Sheet from the Inglefield Land Ice Cap. Lauge Koch noted that the Dodge Glacier ended in an ice cliff, but did not seem to be calving any icebergs, though it probably did occasionally. He noted that Storm Glacier was a relatively crevasse free route onto the higher ice. In 1950 an aerial image from the USGS Satellite image At;as of Greenland, taken by the Danish glaciologist Anker Weidick, of the Dodge and Storm Glacier indicate the terminus of Dodge Glacier ending on northwest side of a valley entering from the valley from the north, red arrow. There is a small glacier flowing down the valley through a nunatak separating the Dodge and Storm Glacier, Dodge Cut, green arrow. The Storm Glacier ends at a small island, orange arrow. The pink arrow indicates an area where the ice slope increases, and bedrock knobs will later emerge. In the second image a Landsat from 1994 the Storm Glacier terminus appears to be at the same location as 1950. The Dodge Glacier has retreated approximately 200 meters from 1950 to 1994. There is still ice in the Dodge Cut, green arrow. There is one new rock outcrop that has emerged south of the pink arrow on the Storm Glacier. In the third image a Landsat from 2012 Storm Glacier has retreated from the island, 350 meters since 1994. Another rock outcrop has emerged from beneath the ice above the Storm Glacier terminus, pink arrow. There is no longer ice flowing through the the Dodge nunatak above Dodge Glacier, green arrow. The Dodge Glacier terminus has retreated 400 meters since 1994. This is a significant increase in retreat rate. Of more importance is that the glacier is now actively calving which was not the case during the Koch expedition or in 1950. The last image in the sequence is a Google Earth view from 2010. dodge and storm glacier 1950 </a

A closeup view of the Dodge Glacier terminus indicates the heavy crevassing near the calving front, indicating that calving will continue, this should lead to more retreat as well. A close up of Storm Glacier indicates the retreat from the small island, which is really a moraine emplaced by the glacier, and noted the brown color of the water entering the bay at the end of the glacier indicating runoff and erosion occurring from beneath Storm Glacier. Dodge and Storm Glacier are retreating like the glaciers to the north and south draining the main ice sheet, Humboldt Glacier and Kong Oscar Glacier.

Sepu Kangri Glacier Retreat, Tibet, China

On January 9, 2013 By mspeltoIn Glacier Observations

There are two glaciers that drain the north side of Sepu Kangri Peak in the Eastern Nyainqêntanglha Mountains of Tibet in China. Most of the peaks in East Nyainqêntanglha Mountains are unclimbed, Sepu Kangri the highest peak was not climbed until 2002. The Sepu Kangri Glaciers drain into thw Salween River.
In a recent study by Tobias Bolch et al (2010) in the western Nyainqêntanglha Mountains glacier area decreased by −6% between 1976 and 2001 and continued to shrink during the period 2001–2009. Li et al (2010) examined glacier change over the last several decades in China and found ubiquitous glacier retreat and commonly lake formation as glaciers retreated. In this case we compare Landsat images from 1988, 2003 and 2010 and Google Earth images from 2011. In 1988 the lakes at the end of the two glaciers are indicated by pink arrows form the main terminus the eastern glacier, and black arrow for the smaller western glacier. By 2003 there is limited terminus change for the main terminus. The western terminus has retreated 200 meters. By 2010 the terminus tongue is breaking up for the eastern glacier terminus. By 2011 the lake has expanded from a length of 600 meters in 1998 and 1300 meters in 2011. The western terminus has retreated another 100 meters. A closeup view in Google Earth of the eastern tongue indicates that this lake will quickly develop to an area of 1.7 km long and 0.8 km wide. Notice all of the icebergs in the lake. This glacier remains heavily crevassed and has a vigorous accumulation zone indicating that it is not in danger of disappearing with current climate.

The formation of lakes at the end of the glaciers is quite common. If we look 10 km east of Supa Kangri are two more developing lakes that we will focus upon later. All of the lakes are in the 4700 and 4800 meter elevation range. The lakes are also common features of retreat in the main Himalayan range for retreating Tibetan glaciers, Reqiang Glacierand Menlung Glacier

Glacier Blanc on Ecrins Retreat, France

On January 6, 2013January 6, 2013 By mspeltoIn Glacier Observations2 Comments

Glacier Blanc is on the east side of Barre Des Ecrins the southernmost of the 4000 m peaks in the Alps. It is the largest glacier on the peak. The glacier began a sustained retreat after 1870, that ceased in 1895-1900 , 1915-1920, 1935-1940 and 1980-1990 (Cossart et al, 2006). The glacier had a mass loss of 11 m from 1981-2005 (Rabatel et al, 2008), which is 5-10% of the total glacier volume. John Hessler, a physical geographer has an excellent series of images from Glacier Blanc, including the image above of terminus change from the Cossart et al (2006) paper. Glacier Blanc was joined with Glacier Noir in 1900, today Glacier Blanc has retreated 1.5 km from the former connection in the St. Pierre River valley, as seen in the image below from Cossart et al (2006).
The series of images below are used to examine the retreat over the last 27 of Glacier Blanc. The first image is a 2003 Google Earth image illustrating the 1985 terminus a pink line, 2003 a purple line and 2010 a red line. The images following are a 1985 Landsat image, pink arrow terminus and blue arrow snowline. The closeup of the terminus in 2003 and 2010 indicates the change in terminus position and stagnant ice. The last image from 2012 notes the 1985 terminus position with pink arrow and the snowline blue arrow. Retreat from 1985 to 2003 was 320 meters, 18 meters/year. From 2003 to 2010 retreat is 250 meters, 36 meters/year. The rate of retreat is increasing. This glacier largest area is the valley basin from 3000 to 3300 meters which is 2.7 km long and 0.9 km long. For the glacier to babove 3200 meters from 2002-2005 (Rabatel et al, 2008). This basin certainly is over deepened and would have a lake if the terminus retreats into it significantly. The glaciers retreat has been similar to that of Glacier de la Girose just 15 km north.

Glacier de la Girose Retreat, France

On January 3, 2013January 6, 2013 By mspeltoIn france glacier retreat, Glacier Observations1 Comment

Glacier de la Grirose (Girose) is one of the most travelled glaciers in the Alps. It is part of the Les 2 Alpes ski resort, used primarily for summer skiing. The main glacier serviced by a lift is Glacier Mantel just to the west of Girose. Despite the frequent visits to the glacier by skiers it has not been the focus of much study. The glacier is smaller than often visited but seldom skied Mer De Glace, similar to Glacier Blanc 15 km south and larger than the Grande Motte at Tignes ski area. Here we examine changes from 1984-2012 using Landsat images, Google Earth images and two photographs. Girose has three termini from west to east labelled A-C. The 1985 terminus location is marked by red arrows, the 2003 terminus is indicated by a purple line, the 2009 terminus by an orange line adn the lip of a key icefall here the middle branch (B) separates from the main branch (C). In 1985 this icefall lip is 500 m above the terminus. The two western termini A and B both extend well below the main icefield of Girose in 1985, by 2012 the tongues barely extend beyond the main glacier. The views of the terminus are in order a 1984 photograph, a 1985 Landsat, 2003 Google Earth, 2010 Google Earth and 2012 Landsat image. They are all viewed from the north. Retreat from 1985 to 2010 has been 420 m at terminus a, 500 m at terminus B and 350 m at terminus C. The overall rate is 15 meters/ year.

Of greater concern is the expansion of outcrops amidst the accumulation zone of the glacier from 2003 to 2010. This indicates thinning in the accumulation zone, which indicates the lack of a persistent snowcover even for many regions high on the glacier. The two images below identify three locations, at A and B the expansion of bedrock is evident. The scale is the same, at point A the rock outcrop is no longer a narrow linear feature. At Point B the rock outcrop is much longer. At point C there is a sharp reduction in crevassing, and the glacier surface is quite dark colored, this is not a rock amidst the glacier, instead the dark area indicates a portion of the glacier surface that has persistently lost its snowcover and where dirt at the surface has been preferentially enriched. This helps speed thinning, but in the former accumulation zone is a sign it is no longer an accumulation zone. The ski season is supposed to extend from mid- June to Sept. 1 for Les 2 Alpes on the glaciers, in many recent years the season is cut short on Girose.

Snowcap Creek Glacier Retreat, British Columbia

On December 31, 2012December 31, 2012 By mspeltoIn Glacier Observations

Snowcap Creek Glacier is one valley north of Stave Glacier in the Garibaldi Provincial Park Region of British Columbia. The retreat of glaciers in this region has been well documented by Koch et al (2009). The response varies from a glacier like the Helm Glacier which is melting away to the Snowcap Creek Glacier which is has been rapidly retreating but has remained vigorous.

Landsat images and Google Earth images are used to document the development of a lake at the terminus of the glacier. In 1992 there is no lake at the main terminus, red arrow or subsidiary terminus at the yellow arrow. There is also a connection between the terminus and the glacier to the north at the magenta arrow. By 2009 there is a new lake at the main terminus that is 700 meters across the glacier reaches the western shore of this lake. A smaller lake has formed at subsidiary terminus, yellow arrow. The terminus is no longer connected to the glacier to the north at the magenta arrow. By 2012 the glacier has retreated 800 meters from 1992 and no longer reaches the western margin of the new unnamed lake, red arrow. The subsidiary terminus lake has expanded but is still less than 100 meters across.

In each image the snowline is noted by a yellow-orange arrow, the glacier continues to have a persistent accumulation, which indicates it can survive current climate. A closer examination of the terminus in 2006 from Google Earth indicates the two new lakes, the detached ice remnant and active crevassing of the glacier surface close to the terminus. In 2006 the glacier terminus still reaches the newly formed lake. The active crevassing begins within 300 meters of the current terminus. The ice tongue reaching down to the lake has already retreated from it and this narrow tongue will be lost soon.

Roosevelt Glacier Retreat, Mount Baker, Washington

On December 27, 2012December 27, 2012 By mspeltoIn Glacier Observations1 Comment

Roosevelt Glacier is on the northwest side of Mount Baker, Washington with its accumulation zone joined with the Coleman Glacier. My first visit to Roosevelt Glacier was in 1984, when the glacier had just completed a 30 year period of advance from 1949-1979. Since 1979 the glacier has been retreating, image below. This post examines Google Earth imagery from 1993, 2003 and 2009 along with field observations from the glacier. The purple line indicates the advance moraine that the glacier emplaced during the 1949-1979 period of advance. We mapped the location of this moraine in 1985, when it was still recent and very evident. The red line is from 1993, yellow line from 2003 and green line from 2009. In 1993 the area below the lip of lava flow cliff is thin and stagnant, cliff noted by purple arrow. By 2003 the glacier has retreated to the top of the cliff and by 2009 the glacier has pulled back from the edge of the cliff. By 2012 the lower glacier, viewed from the edge of the Coleman Glacier, is thin and uncrevassed in the lower 350 meters of the glacier, up to the red arrow. The glacier retreated 190 meters from 1979 to 1993 and 220 meters from 1993 to 2009. The rate of 14 m/year has been relatively consistent.

The glacier is fed by three principal accumulation zones: 1) A glacier tongue that descends from the summit plateau at 3200 meters, 2) an avalanche fed and direct snowfall region beneath the north ridge, at 2200 meters 3) an avalanche and direct snowfall fed region beneath the northwest face, at 2400 meters. The annual snowline has averaged 2150 meters on Roosevelt Glacier from 1984-2010, which has led to a similar retreat of 14 m/year and mass balance loss -0.52 m/year of all Mount Baker glaciers, Pelto and Brown (2012). Each summer we investigate the retained snow depth retained in the crevasse stratified exposures on Mount Baker in the 2400 meter range. Below are several images from this investigation. In the second image the magenta arrows indicate specific annual layers that have been retained. Typical thicknesses are 1.75 to 2.25 m. The next two images are from when we are in an icefall looking for the best exposure to measure the annual layer stratigraphic thickness. The behavior of this glacier parallels that of Deming Glacier, Boulder Glacier and Rainbow Glacier all on Mount Baker.

December 2012 Glacier Post Index

On December 24, 2012 By mspeltoIn Glacier Observations4 Comments

Below is a list of the individual glacier posts examining our warming climates impact on each glacier. This represents the first 3.4 years of posts, 262 total posts, 240 different glaciers. I have worked directly on 46. The others are prompted by fine research that I had come across, cited in each post or inquiries from readers and other scientists. I then look at additional often more recent imagery to expand on that research. The imagery comes either from MODIS, Landsat, Geoeye or Google Earth. There is a consistent signal from the glaciers, mass balance loss, thinning and retreat. In many cases this leads to new lake formation or lake expansion for alpine glaciers. I will continue to record these changes here with a new post twice a week and in the field.

Himalaya
Ngozumpa Glacier, Nepal
West Barun Glacier, Nepal
Khumbu Glacier, Nepal
Imja Glacier, Nepal
Reqiang Glacier Retreat, Nepal
Kali Gandaki Headwaters, Nepal
Samudra Tupa, India
Malana Glacier, India
Sara Umaga Glacier, India
Zemu Glacier, Sikkim
North Lhonak Glacier, Sikkim
Changsang Glacier, Sikkim
Gangotri Glacier, India
Milam Glacier, India
Satopanth Glacier, India
Theri Kang Glacier, Bhutan
Zemestan Glacier, Afghanistan
Emend River Headwaters, Afghanistan
Yajun Peak Glacier, Afghanistan
Godur Glaicer, Pakistan
Tirich Mir, Pakistan
Longbasba Glacier, Tibet
Menlung Glacier, Tibet
Boshula Glaciers, Tibet
Urumquihe Glacier, Tibet
Lumding Glacier, Tibet
Matsang Tsanpo Glacier, Tibet
Dzhungharia Alatau, Kazakhstan
Petrov Glacier,Kyrgyzstan
Hailuogou Glacier, China
Himalaya Glacier Index

Europe
Taconnaz GLacier, France
Mer de Glace, France
Dargentiere Glacier, France
Grand Motte and Pramort Glacier Tignes Ski area, France
Saint Sorlin, France
Sommelier Glacier, France
Obeeraar Glacier, Austria
Rotmoosferner, Austria
Stubai Glacier, Austria
Hallstatter Glacier, Austria
Ochsentaler Glacier, Austria
Pitzal Glacier, Austria
Dosde Glacier, Italy
Presena Glacier, Italy
Forni Glacier, Italy
Careser Glacier, Italy
Lobbia Glacier, Italy
Sabbione Glacier Retreat, Italy
Triftgletscher, Switzerland
Gietro Glacier, Switzerland
Ried Glacier, Switzerland
Cavagnoli Glacier, Switzerland
Chuebodengletscher and Ghiacciaio-del-Pizzo-Rotondo, Switzerland
Peridido Glacier, Spain
Maladeta Glacier, Spain
Engabreen, Norway
Midtdalsbreen, Norway
Tunsbergdalsbreen, Norway
Lodalsbreen, Norway
Rembesdalsskaka, Norway
TungnaarJokull, Iceland
Langjökull, Iceland
Gigjokull, Iceland
Porisjokull, Iceland
Skeidararjokull, Iceland
Kotlujokull, Iceland
Lednik Fytnargin, Russia
Kirtisho Glacier, Georgia
Lednik Kauraugom, Russia
Irik Glacier, Mount Elbrus, Russia

Greenland and European Arctic
Mittivakkat Glacier
Ryder Glacier
Humboldt Glacier
Petermann Glacier
Kuussuup Sermia
Thrym Glacier Retreat
Tiningnilik Glacier Lake
Jakobshavn Isbrae
Zachariae Isstrom
Umiamako Glacier
Alison Gletscher
Kong Oscar Glacier
De Reste Bugt
Qaleraliq Glacier
Upernavik Glacier
Apuserajik Glacier
Epiq Sermia
Sarqardliup Seremia
Steensby Glacier
Sortebrae Glacier, Greenland
Severnaya Zemlya, Russian Arctic
Hansbreen, Svalbard
Nannbreen, Svalbard
Hornbreen and Hambergbreen, Svalbard
Olsokbreen, Svalbard
Albrechtbreen, Svalbard
Roze and Sredniy Glacier, Novaya Zemyla
Nizkiy and Glazova Glacier, Novaya Zemyla

South America
Colonia Glacier, Chile
Artesonraju Glacier, Peru
Nef Glacier, Chile
Tyndall Glacier, Chile
Alemania Glacier, Chile
Zongo Glacier, Bolivia
Sierra Nevade del Cocuy Glaciers, Colombia
Ritacuba Blanco Glacier, Colombia
Llaca Glacier, Peru
Joerg Montt Glacier, Chile
Nororeste Glacier, Chile
Arhuey Glacier, Peru
Seco Glacier, Argentina
Onelli Glacier, Argentina
Quelccaya Ice Cap, Peru
Manon Glacier, Peru
Chuecon Glacier
Glacier Gualas, Chile

Antarctica and Circum Antarctic Islands
Pine Island Glacier
Fleming Glacier
Hariot Glacier
Smith Glacier, Antarctica
Thwaites Glacier, Antarctica
Amsler Island
Stephenson Glacier, Heard Island
Neumayer, South Georgia
Ampere, Kerguelen
Lapparent Outlet, Kerguelen Island
Cook Ice Cap, Kerguelen Island
Nordenskjold Coast, Antarctic Peninsula
Prospect Glacier, Antarctic Peninsula
Ross Hindle Glacier, South Georgia
Vega Island Ice Cap
Rohss Bay, James Ross Island, Antarctica
Jones Ice Shelf, Antarctica

New Zealand
Tasman Glacier
Murchison Glacier
Donne Glacier
Mueller Glacier, NZ
Gunn Glacier, NZ
Douglas Glacier Neve, NZ

Africa
Rwenzori Glaciers
Tyndall Glacier, Kenya

North Cascade Glacier Climate Project Reports

Forecasting Glacier Survival
North Cascade Glacier Mass Balance 2010
Columbia Glacier Annual Time Lapse
North Cascade Glacier Climate Project 2009 field season
28th Field Season Schedule of the North Cascade Glacier Climate Project
North Cascade Glacier Climate Project 2011 Field Season
BAMS 2010 alpine glaciers
BAMS 2011 Alpine Glaciers
2011 Glacier mass balance North Cascades and Juneau Icefield
Taku Glacier TSL Paper
Glacier Ground Truth 2012 North Cascade Field Season
North Cascade Glacier Climate Project 2012 Field Season

Changsang Glacier Retreat and Lake Formation, Sikkim

On December 22, 2012February 8, 2013 By mspeltoIn Glacier Observations3 Comments

Changsang Glacier is a valley glacier just north of Kanchengjunga, the third highest peak, in Sikkim. A comparison of Landsat imagery from 1989 to 2012 identifies the formation of a lake at the end of the glacier. The red arrow indicates the downvalley end of the lake that will develop, the green arrow the upvalley end. In 1989 there is no evidence of a lake either on top of the glacier, supraglacial or proglacial, at the end of the glacier. In 2000 there are a several small lakes beginning to develop. In the 2006 Google Earth imagery the lake is 700 meters long with several other developing smaller lakes. By 2011 the main lake is 1000 meters long and has one debris covered ridge that separates it from a second lake. By 2012 the lake has expanded incorporated the second lake and is now 1500 meters long. The Changsang Glacier was reported to be retreating 22 m/year from 1976 to 2005 (Raina, 2009). In Sikkim 26 glaciers examined were retreating at an average rate of 13.02 m per year from 1976 to 2005 (Raina, 2009) is following the same path as South Lhonak Glacier just to the north and Zemu Glacier just to the south. Zemu Glacier to the south is fed by a higher accumulation zone, and has not been retreating as fast, but it should be anticipated that a lake will form near its terminus.

A closeup view of the terminus area in 2006 indicates the main lake and several smaller lakes that will join the main lake by 2012. The purple arrow indicates the outlet river from beneath stagnant debris covered ice. The orange arrows indicate the extent of the developing lake by 2012.

Kirtisho Glacier Retreat, Georgia

On December 17, 2012December 17, 2012 By mspeltoIn Glacier Observations

The southern flank of the Caucasus Mountains is in the nation of Georgia. Ten kilometers southwest of the Lednik Karaugom Glacier, Russia from the previous post is Kirtisho Glacier a 4.5 km long valley glacier, a small subglacier KS is also examined in this post. The glaciers in the Causcasus Mountains have been undergoing a significant retreat, the USGS, (2010) Satellite Image Atlas of Asia, noted that nearly all of the 65 glaciers examined in this region experienced significant retreat from 1987-2004. Shahgedanova et al, (2009) noted a 8 meters per year average retreat rate for the 1985-2000 period. To get a feel for the terrain watch the trailer for the On the Trails of the Glaciers- Caucasus 2011. The video does not show Kirtisho Glacier but does indicate the nature of the terrain. This is a project of an Italian group Macromicro, that had contacted me about an upcoming expedition to Alaska in 2013. Landsat images from 1986 (second image) and 2012 (third image) along with 2011 Google Earth imagery (top and bottom image) are shown below. Kirtisho Glacier has a top elevation of 3700 meters and a terminus that in 2012 is at 2600 meters, and was 2400 m in 1986. The snowline has typically been at 3300 meters, blue arrow, which is too high to sustain the terminus at 2600 m. The terminus position in 1986 is indicated by a red and yellow arrow that are also used in the 2012 imagery and the 2011 terminus closeup. The magenta arrow in the Landsat images indicates the beginning of a separation from an northern tributary, which is close to the snowline. The terminus itself is not crevassed in the lowest 400 meters, suggesting retreat will continue for this nearly stagnant section. KS the small glacier to the south, has decreased in area from 0.45 km2 in 1986 to 0.20 km2 in 2012. We also examine this more below.

The KS glacier viewed up close is quite thin, with limited crevasses. The red arrows indicate rock protruding through this glacier in many locations. These rocks indicate how thin the ice is, and will help absorb heat and hasten melting as the rock outcrops expand. In 2011 and in the 2012 imagery there is no remaining snow on the glacier. A glacier without a persistent accumulation zone cannot survive (Pelto, 2010). KS glacier will not survive much longer.

Lednik Karaugom Glacier Retreat Caucasus Mountains, Russia

On December 14, 2012February 22, 2014 By mspeltoIn Glacier Observations1 Comment

Lednik Karaugom Glacier is a large 13 km long, valley glacier in the Caucasus Mountains of Northern Ossetia, Russia. The glacier drains into the Urukh River which joins the Terek River and then flows into the Caspian Sea. This post compares Landsat imagery from 1986, 2010 and 2012, an image from the USGS in 2002 and Google Earth imagery from 2009. This glacier has experienced a general retreat like all the glacier draining north from the Caucasus Mountains. USGS, (2010) Satellite Image Atlas of Asia, noted that nearly all of the 65 glaciers examined in this region experienced significant retreat from 1987-2004, noting a retreat of Karaugom of 600 m. Maria Shahgedanova, has an ongoing project examining Caucasus glaciers. Shahgedanova et al, (2009) noted a 8 meters per year average retreat rate for the 1985-2000 period. The glacier retreat has led to an increase in debris cover and an increase in the number of proglacial and supraglacial lakes. (Stokes et al , 2007) This glacier begins at the Russia-Georgia border and extends up to the base of Gora Uilpata at 4200 meters. There is a substantial icefall separating the accumulation zone above 3500 meters from the ablation zone of the valley tongue beginning at 2500 m.from 1987-2002. In the series of images below the yellow arrow indicates the 1986 terminus position, the pink arrow the 2012 terminus position, the orange arrow the 2002 terminus position and the blue arrow the former connection with a tributary. The retreat from 1986 to 2012 is 1300 meters, about 50 meters/year. The retreat of the tributary from the main glacier has been 200 meters, or 8 meters/year.

A closeup of the terminus indicates the amount of debris cover, and the formation of ogives at the base of the icefall. The lateral moraine marking the previous ice surface elevation is also noted with a green arrow. This glacier remains vigorous in its flow, with substantial crevassing and ongoing crevasse formation. The retreat is ongoing but the end of the glacier is not stagnant, though the lower 300 meters has reduced crevassing and width. The degree of crevassing at the green arrows at a small icefall 300 meters above the terminus indicates both ice thickness and flow and suggest that the retreat will likely be reduced in the near future. The behavior is similar to that of Lednik Fytnargin and Irik Glacier on Mount Elbrus