Purvis Glacier Retreat, South Georgia Island

Purvis Glacier is on the norteastern coast of the island, terminating on land near Possession Bay. The British Antarctic Survey (BAS) has mapped many aspects of the island including glacier front changes. Their mapping indicated below shows that the Purvis Glacier terminus was on the coastline in 1974. Here we examine Landsat imagery from 1999 to 2014 to identify more recent changes. Cook et al (2010) quantified the change in these maps noting that 97% of the 102 coastal glacier retreated between the 1950’s and today.
purvis glacier map
BAS map of Glacier change.

purvis ge
Google Earth image

In 1999 the proglacial lake, red arrow, that the glacier terminated in was 300 m wide, indicating a retreat of 300-400 m since 1974. By 2002 the proglacial lake had expanded to a width of 600 m, exposing a peninsula at Point A. By 2013 the proglacial lake had expanded to 1050 m, further exposing the peninsula at Point A. By March 1, 2014 Landsat imagery indicates a retreat of 1100 m since 1974, with most of that retreat occurring since 1979. A closer look at the glacier from Google Earth highlights the issue. The glacier is fed by relatively low lying snowfields with quite limited areas above 500 m. Sugden, Clapperton and I in a 1989 paper identified the snowline a short distance from here at 400 to 450 m. As the 2011 Google Earth image indicates the remaining snowcover at the end of the melt season is minimal, too little to sustain this glacier (Pelto, 2010). Further a look at the terminus indicates the stagnant nature of the terminus region that will lead to continued retreat, blue arrows note ablation holes in the glacier that do not develop when a glacier is actively moving. The low slope and stagnant nature should preserve an excellent glacial geologic landscape.

The glacier is behaving in the same fashion as other land terminating glaciers Heaney Glacier and Konig Glacier. The retreat is less than that of calving glaciers on the island Neumayer Glacier and Ross-Hindle Glacier.
purvis glacier 1999
1999 Landsat image

purvis glacier 2002
2002 Landsat image

purvis glacier 2013
2013 Landsat image

purvis glacier 2014
2014 Landsat image

purvis glacier terminus
Google Earth image

Kluhor Glacier Retreat, Caucasus Mountains, Russia

Kluhor (Klukhor) Glacier is in the Caucasus Mountains west of Mount Elbrus. It drains into the Teberda River and then the Kuban River and eventually Krasnodar Reservoir and the Black Sea. The Krasnodar Reservoir is primarily a flood control and irrigation management reservoir. Here we examine three glaciers each experiencing the familiar pattern in the Caucasus Mountains of retreat with expansion of proglacial lakes. As the area and number of glacier is reduced, the number and area of alpine lakes is increasing, note Khimsa Glacier, Georgia, Psysh Glaciers, Russia, and Gora Bashkara, Russia. Stokes et al (2006) note that 94% of Caucasus Mountain glaciers retreated from 1985 to 2000 and it is clear from the aforementioned that the trends continues.
klukhori glacier ge lg

We examine Landsat imagery from 1998 and 2013 to identify the change. In each image the Kluhor Glacier terminus lake is indicated by the red arrow. The unnamed Glacier here named east Kluhor Glacier terminus lake is noted with a yellow arrow. Another unnamed glacier on Lednik Daut is identified here as north Daut Glacier is noted by pink and purple arrows. In 1998 there is small lake at the end of Upper Kluhor Glacier, 150 m long, and on east Kluhor Glacier, 50-100 m wide. At north Kluhor Glacier the glacier ends at the base of a steep icefall near a third lake, pink arrow. The purple arrow indicates the terminus of north Daut Glacier in each image. By 2013 Kluhor Glacier has retreated 300 m and the lake is 450-500 m long. The east Klhor Glacier has retreated 150 m and the lake is 250 m across. The north Daut Glacier has retreated to the top of the steep icefall slope, a 400 m retreat and is now quite distant from the lake below.

The 2007 Google Earth image of Kluhor Glacier there are a number of crevasses paralell to the ice front, indicating that some calving losses will continue to occur. The glacier overall extends from 2950 m to 3250 m, is narrow and has limited snowcover in both satellite images. The snowcover extent in the August satellite images, well before the end of the melt season is 30%, whereas typically 55-65% is necessary to sustain a glacier. In the 2007 Google Earth imagery the thin nature of the icefall at north Daut Glacier is evident, that has since melted away.
kluhor Glacier 1998
1998 Landsat image

kluhor glacier 2013
2013 Landsat image

klukhori glacier lake
2007 Google Earth image of Kluhor Glacier

klukhori glacier n
2007 Google earth image north Kluhor Glacier

Psysh Glacier Retreat, Western Caucasus, Russia

Psysh Mountain is in the western Caucasus just north of the Georgia-Russia border. This is the western most significant glacier complex in the Caucasus, here we focus on a glacier flowing east from the mountain and another on the north side. The east flowing glacier drains into the Psysh Valley and then to Arkhyz, while the north flowing glacier drains into the Zagedan River. The Caucasus region has been experiencing widespread significant retreat (Shahgedanova et al 2009), with average retreat of 8 m per year due in large part to increased summer temperatures. The larger glaciers of Mount Elbrus tend to garner most of the attention, but the retreat is widespread. This region has been an area of increased proglacial lake formation as well Stokes et al (2007). Psysh Mountain is 115 km east of Sochi, Russia. The glaciers mean elevation is 3000 m, more than 1000 m above the higher elevations of the Sochi Olympic skiing venues.

Here we examine the glacier retreat in Landsat imagery from 1998 to 2013. In 1998 the two glaciers of interest on the mountain ended in incipient proglacial lakes, less than 100 m across, yellow and red arrow. By 2013 the lake at the red arrow has expanded to a length of 400 m that the east flowing glacier ends in. The lake at the terminus of the north flowing glacier is now 350 m long. This indicates a retreat of 300 m for both glaciers. The pink arrow indicates the expansion of bedrock in the midst of the north flowing glacier. In the Google Earth image the most striking feature is how little of the glacier is above the snowline. In each image the snowline is indicated with pink dots. It is evident that neither glacier has a persistent significant accumulation area. These glaciers cannot survive without a persistent significant accumulation zone (Pelto, 2010). The blue arrow in the Google Earth image indicates an icefall in the east flowing glacier. Below the icefall the glacier has a low slope and is stagnant. This basin’s extent suggests the lake can expand another 1 km. The retreat of this glacier is similar to that of Gora Bashkara Glacier and Lednik Karugom.

psysh Glacier 1998
1998 Landsat image

psysh Glacier 2013
2013 Landsat image

psysh ge
2012 Google Earth Image

White River Glacier Disequilibrium Retreat, Washington

White River Glacier in the North Cascades of Washington is on the southeast flank of Glacier Peak. From 1955-1967 White River Glacier had a stable though thinning terminus. In 1967 the glacier descended from the summit area of Kololo Peak separating into two terminus tongues ending in two basins. In both basins the glacier terminus filled the basins and flowed a short distance beyond the basins. During my first visit to the glacier in 1988 there was the fringe of a new lake for both the northern and southern arm of the glacier at the yellow and red arrow respectively, with retreat of both termini into the basin, 60 m of retreat. The southern terminus is fed by an icefall green arrow.White River 67
1967 Image from Austin Post (USGS)

White River 88
1988 image

By 1995 when we returned the northern branch of the glacier, red arrow, had developed a lake that was 150 m across, and the terminus was in contact with the lake. The southern basin was still mostly ice filled, with 60 m of open water at the southeast corner. In 2002 we revisited the glacier the northern basin terminus had retreated 20 m from the lake. The southern basin was still filled with glacier ice, but this ice was now flat and floating in the water. There were numerous water filled cracks. The lake was 265 m across. By 2002 the terminus had retreated out of the southern lake basin ending at the base of the icefall slope. The lake is evident even with its floating glacier ice cover. In 2006 and 2009 Google Earth imagery the retreat of the southern terminus up the icefall slope is evident. In 2013 there is still floating glacier ice in the southern lake basin, image from Stefan Feller. The glacier retreat of the northern terminus from 1967-2013 has been 370 m, the southern terminus 450 m. The main issue for this glacier is that the upper part loses snowcover during many years. This means the glacier is having a disequilibrium response to climate and will not survive (Pelto and Hedlund, 2001). Thinning and retreat of the upper glacier indicates the lack of a persistent accumulation zone, hence the glacier cannot survive our greenhouse warmed climate, leaving mother nature less than pleased. Advertising Illustration A1
Mother Nature sketch from Megan Pelt-Savannah College of Art and Design

(Pelto, 2010). This glacier’s retreat paralells that of two adjacent glaciers Honeycomb and Whitechuck , but is greater than on adjacent Suiattle Glacier

White River Glacier 95
1995 view of northern terminus from 1967 terminus location

white river glacier 2002
2002 glacier view with southern terminus

white river 2006
2006 Google Earth image

white river2 2009
2009 Google Earth image

white river glacier 2013
2013 image from

Walker Glacier Retreat and Lake Development, Alaska

Walker Glacier terminates adjacent to the Alsek River, a popular rafting river route. Many rafting trips visit Walker Glacier since it is close to river, has a low slope and few crevasses.
walker glacier ge
Google Earth Image

In 1984 the glacier ended as a piedmont lobe separated from the river by meters. Today the terminus has retreated into a lake basin at the terminus. Here we examine Landsat imagery from 1984, 2011 and 2013 to identify retreat and lake development. In 1984 there is no lake at the terminus, red dots indicate glacier margin. The terminus particularly on the northwest side is debris covered. The yellow and red arrows indicate locations where the terminus is in 2013 and where new lakes have developed. The pink arrow indicates the end of a tributary that has fed the Walker Glacier. By 2004 the Google Earth imagery indicates a lake that is 400 m wide and 1500 m long. By 2011 the lake on the north side of the terminus is well developed, yellow arrow, but on the west side of the terminus no lake exists, red arrow. By 2013 the new lake is 750 m wide and 1800 m long. The glacier has retreated 800 m since 1984 on the north side, yellow arrow. A narrow lake has now developed on the west side. The combination of lakes indicates that the entire terminus lobe in the lake basin will soon be lost. The terminus remains quite debris covered, has a gentle slope and is relatively uncrevassed; hence, it is stagnant and will collapse-melt away. The last image is from Colorado River & Trail Expeditions , that shows low glacier slope looking north across new lake. This is similar to the collapse of glacier termini in proglacial lakes such as nearby East Novatak Glacier, Grand Plateau Glacier and Yakutat Glacier. walker glacier 1984
1984 Landsat image

walker glacier 2011
2011 Landsat image

walker galcier 2013
2013 Landsat image

walker glacier terminus
Google Earth image from 2004

Walker glacier lake
Colorado River & Trail Expeditions image-note low glacier slope looking north across new lake.

Mueller Glacier retreat Lake Expansion, New Zealand

Volume loss in New Zealand glaciers is dominated by 12 large glaciers. The NIWA glacier monitoring program has noted that volume of ice in New Zealand’s Southern Alps has decreased 5.8 cubic kilometres, more than 10% in the past 30 years. More than 90% of this loss is from 12 of the largest glaciers in response to rising temperatures over the 20th century. Three of these glaciers are the Tasman, Mueller and Hooker Glacier. Mueller and Hooker Glacier are one valley west of the Tasman Glacier and end in the same valley ending just 3 km apart. Description of the retreat and the role of glacier lakes in accelerating the reteat of Tasman Glacier is discussed in detail in Dykes et al (2011). If we look back to the 1972 Mount Cook Map no lakes are evident at the terminus of Hooker (H), Mueller (M) or Tasman Glacier(T), pink dots indicate terminus location, top image. In 2011 the Landsat image illustrates that this has become a new lake district, bottom image.. Mueller Glacier drains the eastern side of Mount Sefton, Mount Thompson and Mount Isabel. The lower section of the glacier is debris covered in the valley reach from the terminus at 1000 m to 1250 m. A comparison of the Mueller Glacier in a sequence of three Landsat images below from 2000 (top), 2004 (middle) and 2011 (bottom), indicates that the lake at the end of Hooker Glacier had developed by 2000. The lake at the end of the Mueller Glacier was just forming length of 400 meters. By 2004 the Mueller Glacier Lake had expanded to a length of 700 meters. By 2011 the lake had reached 1400 meters in length. The 1000 meter retreat from 2000-2011 will continue in the future as the lower section is stagnant. . A closer look at the lower Mueller Glacier indicates that the lower 2 km is stagnant as indicated by the formation of supraglacial lakes and considerable surface roughness (green arrow) that does not occur when a glacier is active and moving. The glacier has been fed by three different glaciers flowing off of Mount Sefton. Two of them Tuckett and Huddlesoton (pink arrow) are no longer delivering significant ice to the Mueller, only modest avalanching now spills onto the Mueller Glacier. Only the Frind Glacier (yellow arrow) is contributing to the Mueller Glacier. The result is that the end of truly active ice is at the purple arrow, this will develop into the terminus of the Mueller Glacier. In the 2011 image of the glacier the yellow-burgundy arrow indicates the snowline on the Frind Glacier is at 1900 meters, yielding too small of an accumulation zone to support the valley tongue of the Mueller Glacier. This is similar to the situation on nearby Murchison Glacier. Further the lack of ice connection from Huddleston and Tuckett Glaciers to Mueller is again evident, pink arrow. The lake will continue to expand through minor calving and downwasting. The lake has not been surveyed, but seems to lack the depth at the current terminus of Tasman Lake where calving can be more important.

Eagle Glacier Retreat, Juneau Icefield Alaska

eagle glacier changeAbove is a paired Landsat image from 1984 left and 2013 right indicating the 1100 m retreat during this period of Eagle Glacier.My first visit to the Eagle Glacier was in 1982 with the, ongoing and important, Juneau Icefield Research Program, that summer I just skied on the glacier. In 1984 we put a test pit at 5000 feet near the crest of the Eagle Glacier to assess the snowpack depth. This was in late July and the snowpack depth both years was 4.3 meters, checking this depth in nearby crevasses yielded a range from 4-4.5 meters. In 1984 the snowline at the end of the summer melt season in early September was at 1050 meters. In the image below the glacier is outlined in green, the snowpit location is indicated by a star and the snowline that is needed for the glacier to be in equilibrium at 1025 meters is indicated.
Eagle Glacier has experienced a significant and sustained retreat since 1948. The first map image below is of the glacier in 1948, at this time the glacier ended at the south end of a yet to be formed glacier lake. By 1982 when I first saw the glacier and when it was mapped again by the USGS (second image) the glacier had retreated to the north end of this 1 kilometer long lake. In the sequence of images the red line is the 1948 terminus, the magenta line the 1982 terminus, the green line 2005 terminus and the orange line the 2011 terminus. From 1982 to the 2005 image used in Google Earth the glacier retreated 500 meters, 21 meters/year (next image). The bottom image is from a 2011 Landsat image in May and indicates the terminus position once again with an additional retreat in six years of 400 meters, 65 meters/year. Going back to the 1948 map the terminus in 2011 is located where the ice was 500-600 feet thick in 1948The more rapid retreat follows the pattern of more negative balances experienced by the glaciers of the Juneau Icefield (Pelto et al, 2008). The Equilibrium line altitude which marks the boundary between the accumulation and the ablation zone each year is a good marker of this. On Eagle Glacier to have an equilibrium the glacier needs to have an ELA of 1050 meters. At this elevation more than 60% of the glacier is in the accumulation zone. Satellite imagery allows identification of the ELA each year, seen below is the elevation in 1984, 1998, 1999 and each year since 2003. The number of years where the ELA is well above 1050 meters dominate leading to mass loss, thinning and glacier retreat. This follows the pattern of Lemon Creek Glacier that is monitored directly for mass balance, which has lost 26 meters of thickness on average since 1953.

Grand Plateau Glacier Retreat, Alaska

Grand Plateau Glacier drains southwest from Mount Fairweather in southeast Alaska. The glacier advanced during the Little Ice age to the Alaskan coastline. Early maps from 1908 show no lake at the terminus of the glacier. The 1948 map shows three small distinct lakes at the terminus of the main glacier and a just developing lake at the terminus of the southern distributary terminus (D). By 1966 the glacier had retreated enough for the formation of one lake. The distance from the Nunatak N to the terminus was 12 km in 1948. The lake at D is 400 m wide.gp-terminus

gptribmap
USGS map displayed in Google Earth-1948 base images.

Landsat images from 1984, a Google Earth Mosaic of the 2003-2009 period and a Landsat image from 2013 indicate the substantial changes that have occurred. Here both the main terminus and a distributary (D) terminus draining south are examined. The main reference points in each image are the Nunatak, N, and and Island, I. The retreat from 1984-2013 is evident with the yellow arrows indicating the 1984 terminus and pink arrows showing the 2013 terminus location. The distance from the Nunatak to the terminus is 9.6 km in 1984, 6.8 km in the Google Earth image and 3.5 km in 2013. A six kilometer retreat at the glacier center in 30 years. On the north shore of the lake the retreat between arrows is 2.7 km from 1984-2013. From the island the glacier retreated 3.3 km from 1984-2013. The distributary tongue (D) retreated 2.2 km from 1984-2013. The offset of the terminus is 300-350 m indicating a five year retreat rate of 75-90 meters per year. The retreat has been driven by higher snowlines in recent years, the snowline had been reported at 3400 feet in the 1950’s. Satellite imagery of the last decade indicates snowlines averaging 1500 m, red arrows. The glacier snowline is evident in Landsat imagery in 2009 and 2013 red arrows. The combination of higher snowlines and increased calving into the terminus lake will continue to lead to retreat of this still mighty river of ice. This retreat parallels that of nearby Yakutat Glacier, Norris Glacier and Melbern Glacier
grand plateau 1984
1984 Landsat image

grand plateau 2013
2013 Landsat image

grand plateau ge
Google Earth images

Mer de Glace, Glacier Retreat-A Receding Sea

Mer De Glace drains the north side of Mont Blanc. This is the largest glacier in this section of the Alps, it is 12 km long. The “sea of ice” terms not only refers to the size of the glacier, but also to the ogives, curved color bands formed at the base of the icefall. This sea of ice is slowing down as well as thinning and retreating. This has led to the lowest 12% of the glacier being stagnant and appears ready to melt away in the coming decades. A new paper Vincent et al (2014) model Mer de Glace into the future and generate a retreat of 1200 m by 2040, this is likely a minimum.
Post has been relocated and update at
Mer de Glace

Devon Ice Cap

Two recent papers have examined the changes in flow, mass balance and volume of the Devon Ice Cap(Shepherd et al., 2007) (Dowdeswell, 2004). The Devon Ice Cap on Devon Island in the Canadian Arctic ice cap’s area has an area of 14,000 km2, with a volume of 3980 km3 . The ice cap area decreased by 332 km2 (2.4%) between 1960 and 2000.devon ice cap
The mass balance of the glacier has been assessed since 1960, the total mass loss due to surface melting and runoff between has been about 59 km3. Between 1960 and 1999 about 21 km3 of ice was lost from the ice cap by calving of icebergs, contributing 0.21 ± 0.02 mm to global sea level over this time. The long term mean net surface mass balance was 0.13 m from 1960-2000. From 1998-2007 the mean annual balance has been -0.23 m year, a substantial increase. belcher glacier The Belcher Glacier above is the principal outlet glacier calving up to 30% of the total iceberg volume from the ice cap.
Devon Ice Cap’s negative balance has been due to warming and greater ablation, as the upper part of the glacier has seen some increase in accumulation, which has been more than offset by increased melting. dic mbIn this case the mass balance record indicates a dramatic worsening after 1995. It will be interesting to see the ablation results from the summer of 2008, when record melting was noted both in northern Greenland and northern Ellesmere Island. The glacier is not alone in its behavior, the Prince of Wales Icefield has had a negative mass balance over the last forty years of -80 km3, equivalent to a mean-specific mass balance across the ice field of -0.1 m w.e. a-1, contributes 0.20 mm to global eustatic sea level rise (Mair et at., 2008).
Photographs of the fieldwork coordinated by the University of Alberta