Index of Glacier Posts June 2009-June 2011

On June 25, 2011June 26, 2011 By mspeltoIn Glacier Observations1 Comment

New Zealand
Tasman Glacier
Murchison Glacier
Donne Glacier
Africa
Rwenzori Glaciers
Himalaya
Zemu Glacier, Sikkim
Theri Kang Glacier, Bhutan
Zemestan Glacier, Afghanistan
Khumbu Glacier, Nepal
Imja Glacier, Nepal
Gangotri Glacier, India
Satopanth Glacier, India
Menlung Glacier, Tibet
Boshula Glaciers, Tibet
Urumquihe Glacier, Tibet
Sara Umaga Glacier, India

Europe
Mer de Glace, France
Dargentiere Glacier, France
Obeeraar Glacier, Austria
Ochsentaler Glacier, Austria
Pitzal Glacier, Austria
Dosde Glacier, Italy
Maladeta Glacier, Spain
Presena Glacier, Italy
Triftgletscher, Switzerland
Rotmoosferner, Austria
Stubai Glacier, Austria
Ried Glacier, Switzerland
Forni Glacier, Italy
Peridido Glacier, Spain
Engabreen, Norway
Midtdalsbreen, Norway
TungnaarJokull, Iceland
Gigjokull, Iceland
Skeidararjokull, Iceland
LLednik Fytnargin, Russia
Rembesdalsskaka, Norway

Greenland
Mittivakkat Glacier
Ryder Glacier
Humboldt Glacier
Petermann Glacier
Kuussuup Sermia
Jakobshavn Isbrae
South America
Colonia Glacier, Chile
Artesonraju Glacier, Peru
Nef Glacier, Chile
Tyndall Glacier, Chile
Zongo Glacier, Bolivia
Llaca Glacier, Peru
Seco Glacier, Argentina
Antarctica and Circum Antarctic Islands
Pine Island Glacier
Fleming Glacier
Hariot Glacier
Amsler Island
Stephenson Glacier, Heard Island
Neumayer, South Georgia
Ampere, Kerguelen

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

Gilkey Glacier Ogive Spacing and Retreat

On May 29, 2011April 1, 2014 By mspeltoIn alaska glacier retreat, Glacier Observations3 Comments

The Gilkey Glacier is a 32 km long outlet glacier flowing west from the Juneau Icefield. From 1948 to 1967 the Gilkey Glacier retreated 600 m and in 1961 a proglacial began to form. By 2005 Gilkey Glacier has retreated 3900 m from the 1948 terminus location. The glacier is currently terminating in this still growing lake, notice the new bergs and rifting at the glacier terminus. The retreat has been resulted from and in a thinning of in the lower reach of the glacier and the separation from Battle and Thiel Glacier. A major tributary to Gilkey Glacier, is Vaughan Lewis Glacier. At the base of the Vaughan Lewis Icefall where the Vaughan Lewis Glacier joins the larger Gilkey Glacier ogives form, as seen from above and below the icefall (Scott McGee). The ogives form annually and provide a means to assess annual velocity in this section of the glacier. Aerial photography of the ogives from the 1950’s combined with current satellite image provide the opportunity to assess ogive wavelength over a 50 year period, providing a long term velocity record for Gilkey Glacier. An ogive is a bulge-wave that forms annually due to a seasonal acceleration of the glacier through an icefall. The acceleration is enhanced in icefalls that are horizontally restricted. In most cases we do not have specific measurements of velocity through all season to ascertain the timing of the accelerated period, though typically spring would be the fastest. After formation the bulges move down glacier and a new bulge is formed the following year. The resulting train of ogives extending down glacier can be used to estimate the ice velocity by measuring the peak to peak separation between adjacent waves. Ogives can be visually identified as a series of arcuate wave crests and troughs pointing down glacier. Downglacier from this formation point the crests and troughs gradually flatten until the ogives are merely arcuate light and dark bands on the surface of the glacier. The dark bands are dense, blue and dusty ice that is compressed during summer, whereas the light bands are bubbly, white, air-filled ice that is compressed during winter.
In 1981 one of my tasks was to ski out through the top of the icefall inserting stakes in the crazily crevassed region to track summer velocity for the Juneau Icefield Research Program (JIRP). This has been completed often but not most years by JIRP. What we discovered was that velocity in 1981 had not changed from the 1960’s and 1970’s. Today we have frequent satellite imagery of the ogives to ascertain annual velocity that can be compared to the few aerial photographic records, in this case from 1056 and 1977. In several recent years Scott McGee of JIRP has specifically surveyed the distance between the first 11 ogive crest below the icefield. A comparison of the the ogives in 1956, 1977 and 2005 is possible by overlaying the images below. . The distance from the first to the 40th ogive has gone from 6.8 km in 1956 to 6.75 km in 1977 to 6.2 km in 2005. In 1956 and 1977 the first ten ogives spanned 1500 meters indicating an annual glacier velocity of 150 meters. From 2003-2007 the distance of the first ten ogives averaged 1440 m, or 144 meters per year. The change in velocity is quite small, compared to the large retreat of the glacier. One other key measure of the ogive surveying program is the surface elevation. A longitudinal profile containing 179 survey points was established at the base of the Icefall in 2001-2007. This profile begins in the trough immediately upglacier of the crest of the first wave ogive and continues downglacier nearly 1.8 kilometers to a point where the amplitude of the ogives becomes zero (Graphs and data from JIRP) During this six year time period, the surface has lowered an average of 17 meters – nearly 3 meters per year – along the longitudinal survey profile, with a maximum of 22 meters. This substantial thinning at the base of the icefall indicates reduced discharge through the icefall from the accumulation zone above. This will lead to further retreat and velocity reduction of Gilkey Glacier.

Llaca Glacier Retreat, Peru

On December 2, 2010December 2, 2010 By mspeltoIn Glacier Observations

The Cordillera Blanca, Peru has 27 peaks over 6,000m, over 600 glaciers and is the highest tropical mountain range in the world. Glaciers are a key water resource from May-September in the region, Mark (2008). The glaciers in this range have been retreating extensively from 1970-2003, GLIMS identified a 22% reduction in glacier volume in the Cordillera Blanca. Vuille (2008) noted that the retreat rate has increased from 7-9 meters per year in the 1970’s to 20 meters per year since 1990. One of the glaciers that is continuing to recede is Llaca Glacier descending the west slopes of Ranralpaca. This glacier has retreated 1700 m from its Little Ice Age moraine, outlined in lime green. Llaca Laguna is impounded by this moraine. The glacier still has a significant consistent accumulation zone and can survive current climate. Stagnant pockets of debris covered ice no long connected to the glacier fill much of the valley between the laguna and the current glacier. The terminus despite ending on a steep slope lacks significant crevassing indicating a lack of vigorous flow which will lead to continued retreat of 20-30 meters per year. This glacier drains into the river which then flows into the Rio Santa in Huarez, Peru. Mark (2008)note the importance of glaciers to the Cordillera Blanca watersheds in the Huarez region receive 35% of their runoff from glaciers, and the upper Rio Santa likely receives 40%.

Stephenson Glacier retreat, Heard Island

On November 4, 2010November 4, 2010 By mspeltoIn Glacier Observations

The Australian Antarctic Division manages Heard Island Island and has undertaken a project documenting changes in the environment on the island. One aspect noted has been the change in glaciers. The Allison, Brown and Stephenson Glacier have all retreated substantially since 1947 when the first good maps of their terminus are available. Fourteen Men by Arthur Scholes (1952) documents a year spent by fourteen men of the Australian National Antarctic Research Expedition. Their visit to the glacier noted that they could not skirt past the glacier along the coast. After crossing Stephenson Glacier they visited an old seal camp and counted 16,000 seals in the area Ensuing mapping and aerial photography has enabled a sequence of glacier boundary maps to be created that illustrate the changes in the glaciers. Thost and Truffer (2008) noted a 29% reduction in area of the Brown Glacier from 1947-2003. They also observed that the volcano Big Ben that the glaciers all drain from has shown no sign of changing geothermal output to cause the melting and that a 1 C warming has occurred over the same time period. Stephenson Glacier extends 8-9km down the eastern side of Big Ben. it 1947 it spread out into a piedmont lobe that was 3 km wide and extended to the ocean in two separate lobes around Elephant Spit. A picture from the Australian Antarctic Division taken in 1947 shows the glacier reaching the ocean and then in 2004 from the same location. around then broadens to form a piedmont lobe up to -3 km wideKiernan and McConnell (2002) an order of magnitude increase in the rate of ice loss from Stephenson Glacier after 1987. Retreat from the late 19th century to 1955 had been limited. As Kiernan and McConnell observed retreat began to increased and by 1971 the glacier had retreated 1 km from the south coast and several hundred meters from the northern side of the spit. This retreat by 1980 caused the formation of Stephenson Lagoon and by 1987 Doppler Lagoon had formed as well. After 1997 the two lagoons have joined as Stephenson Glacier has retreated rapidly. The terminus is now 2.2 km from the south coast and 3.1 km from the north coast. The highly crevassed area above the terminus indicates the rapid ongoing flow of the glacier. The terminus is highly fractured in Google Earth Imagery indicating this section will continue to retreat via calving of icebergs into the lagoon, which is quite full as it is. The first image below shows the terminus location over the last 60 years from the Australian Antarctic Division. The second image are the AAD overlays that can be imported into Google Earth. The last image is a closeup of the still disintegrating terminus into the combined lagoons from 2008. The Stephenson Glacier is undergoing a rapid calving retreat that began due to ongoing mass balance loss. This mass balance loss is shared by the other glaciers on the island are observations, though the actual terminus retreat may be less the volume losses of Brown Glacier recently have been large.

Ried Glacier Rapid Glacier loss, Switzerland

On October 14, 2010October 14, 2010 By mspeltoIn Glacier Observations

Ried Glacier is beneath the Durrenhorn in the Pennine Alps of Switzerland. The glacier was 6.3 km long in 1973. In 2010 the glacier is 5.1 km long. From the Swiss Glacier Monitoring Network annual measurements, Ried Glacier retreated 300 m from 1955-1990, 8 meters/year. From 1990-2008 retreated an additional 300 m, 30 m/year. Than in 2009 the glacier retreated 500 m. A comparison of a 2004 image taken by M. Funk and a Sept. 2008 image from D. Gara indicate why the change was so abrupt. The glacier had been retreating upvalley with a long gentle terminus tongue. This section of the glacier separated from the glacier in late 2008, with the terminus now ending on a steep rock slope. There is still stagnant ice in the valley below the end of the current glacier. It is heavily debris covered and no longer connected to the glacier system. This glaciers recent rapid retreat parallels that of Dosde Glacier, Italy and Triftgletshcer, Switzerland and Rotmoosferner, Austria. A look at the glacier system and the terminus in Google Earth imagery provides a broader view of the glacier behavior. The terminus in this image still extends downvalley with the low sloping tongue that is now separated. Current terminus marked with red-T.
In the imagery above the glacier is still connected to the terminus tongue. It is evident that the glacier has two primary icefalls at that time. The upper icefall is the location of the annual snowline, where accumulation tends to persist throughout the year. Below this point only seasonal snowfall is retained. The retreat history from the Swiss Glacier Monitoring Network is seen below.

Lemon Creek Glacier Retreat Juneau Icefield Alaska

On July 26, 2010December 8, 2013 By mspeltoIn Glacier Observations2 Comments

Above is a paired Landsat image with 1984 left and 2013 right, indicating a 300 m retreat in this interval.

Annual balance measurements on the Lemon Creek Glacier, Alaska conducted by the Juneau Icefield Research Program from 1953 to 2013 provide a continuous 61 year record. This is one of the nine American glaciers selected in a global monitoring network during the IGY, 1957-58 and one of only two were measurements have continued. These show cumulative ice losses of –13.9 m (12.7 m we) from 1957-1989, of –19.0 m (-17.1 m we) from 1957-1995 and –24.4 m (–22.0 m we) from 1957-1998. The mean annual balance of the 61 year record is -0.43 m/a and a loss of at least 30 m of ice thickness for the full 61 year period from 1953-2013. In the second graph the similarity with other North American glaciers is evident (Pelto et al, 2013).

This negative mass balance has fueled a terminal retreat of 800 m during the 1953-1998 period, and an additional 200 meters of retreat by 2013. Below is a picture of the terminus enroute to Camp 17 in 1982, and below that from 2005. The annual balance trend indicates that despite a higher mean elevation and a higher elevation terminus, from thinning and retreat, mean annual balance has been strongly negative since 1977 (-0.60 meters per year). Dramatically negative mass balances have occurred since the 1990’s, with 1996, 1997 and 2003 being the only years with no retained accumulation since field observations began in 1948.

These data have been acquired primarily by employing consistent field methods, conducted on similar annual dates and calculated using a consistent methodology. The research is conducted from Camp 17 on a ridge above the glacier. This is a wet and windy place with three out of four summer days featuring mostly wet, windy and cool conditions in the summer. The camp was initially built for the IGY in 1957, and Maynard Miller and Robert Asher saw to its continued improvements through the 1980’s. The mass balance record have been were until 1998 precise, but of uncertain accuracy. Then two independent verifications indicated the accuracy (Miller and Pelto, 1999). Comparison of geodetic surface maps of the glacier from 1957 and 1989 allowed determination of glacier surface elevation changes. Airborne surface profiling in 1995, and comparative GPS leveling transects in 1996-1998 further update surface elevation changes resulting from cumulative mass balance changes. Glacier mean thickness changes from 1957-1989, 1957-1995 and 1957-1998 were -13.2 m, -16.4 m, and –21.7 m respectively. It is of interest that the geodetic interpretations agree fairly well with the trend of sequential balances from ground level stratigraphic measurements. The snowline of the glacier lies a short distance above a tributary glacier from the north that has separated from the main glacier since 1982. The snowline on the glacier was just below this juncture in the 1950’s and 1960’s but now has typically been above this former juncture. The two images below are looking down and upglacier from this former tributary in 2005.

At the head of the glacier is a supraglacial Lake Linda, which now drains under the ice. Robert Asher in the late 1970’s and 1980’s mapped this lake system when it drained under the head of the glacier not down under the terminus of the glacier.

On July 8, 2010February 5, 2013 By mspeltoIn Glacier Observations, Uncategorized4 Comments

The Lower Curtis Glacier on Mount Shuksan advanced from 1950-1975 and has retreated 150 meters from 1987-2009. A longitudinal profile up the middle of the glacier indicates that it thinned 30 meters from 1908-1984 and 10 m from 1984-2008. Compare the 1908 image taken by Asahel Curtis (glacier named for him) in 1908 and our annual glacier shot in 2003. The thinning has been as large in the accumulation zone as at the terminus, indicating no point to which this glacier can retreat and achieve equilibrium with the present climate. However, the glacier is quite thick, and will take 50-100 years to melt away. This glacier is oriented to the south and fed by avalanches from the Upper Curtis Glacier and the southwestern flank of Mt. Shuksan. This allows it to survive in a deep cirque at just 5600 feet. Because of its heavy accumulation via avalanching the glacier moves rapidly and is quite crevassed at the terminus. Image below is a 2009 sideview, note the annual dark layers in the ice. The number of crevasses in the nearly flat main basin of the glacier has diminished as the glacier has thinned and slowed over the last 20 years. The glacier lost nearly all of its snowcover in several recent years 2005, 2006 and 2009. In one month we will back on this glacier investigating its mass balance and terminus position. It is a key glacier this year, as the winter was quite warm yet wet, spring was not. Thus, snowpack was much below average below 5000 feet and likely above average above 7000 feet, where the transition will be is the key. In the google earth images below Lower Curtis Glacier is in the left center. The terminus is exposed bare glacier ice and is heavily crevassed. Typically the terminus loses its snowcover in mid-June. Below the terminus there are frequent ice and rock falls, so it is best not to go below the terminus. For our measurements we need to, but we always finish by 9 am. .

Boulder Glacier Retreat, Mount Baker

On January 9, 2010June 7, 2013 By mspeltoIn Glacier Observations

Boulder Glacier flows down the west side of Mount Baker a strato volcano in the North Cascades of Washington. This steep glacier responds quickly to climate change and after retreating more than 2 kilometers from its Little Ice Age Maximum, it began to advance in the 1950’s as observed by William Long. The glacier advance had ceased by 1979. From 1988-2008 we (NCGCP) have visited this glacier at least every five years recording its changes. In 1988 the glacier had retreated only 25 meters from its furthest advance of the 1950-1979 period. By 1993 the glacier had retreated 100 m from this position. At this time the lower 500 meters of the glacier was clearly stagnant. By 2003 the glacier had retreated an additional 300 m. In 2008 the glacier had retreated 490 meters from its 1980 advance position, a rate of 16 meters per year. The glacier as seen in 2008 despite the steep slope has few crevasses in the debris covered lower 400 meters of the glacier. This indicates this section of the glacier is stagnant and will continue to melt away. The transition to active ice in at the base of the icefall on the right-north side of the glacier. Below is the glacier in 1993 note the darkened cliff at adjacent to and right of the terminus. The picture below that is from 1998 again note cliff, than in 2003 from the same location as the 1993. Than an image from 2008 of the terminus from further upvalley, as it is not clearly in view from the previous location. And a picture from Asahel Curtis taken in 1908. This glacier after 25 years of retreat is still not approaching equilibrium and will continue to retreat. This is a reflection of continued negative mass balance as measured on the adjacent Easton Glacier. It does respond fast to climate change, and the climate has not been good for this glacier. The glacier does have a consistent accumulation zone and can survive current climate.Picture from August, 1993 of the terminus of Boulder Glacier Picture from August 1998 of the terminus of Boulder GlacierPicture from August 2003 of the terminus of Boulder Glacier.Boulder Glacier in August 2008. Boulder Glacier in 1908 viewed across the glacier at the present terminus location during a Mountaineers trip taken by Asahel Curtis. A satellite image from 2009 (green=2009, brown=2006, purple=1993 yellow=1984), shows additional retreat now at 515 meters from 1984 to 2009, 20 meters per year. An examination of the same view of the terminus in 1993 and 2009 indicates the extent of the retreat and the reduction in crevassing below the icefall. (

For 30 years the North Cascade Glacier Climate Project has focused on observing the response of glaciers to climate change.

Grasshopper Glacier, Montana-nearly gone

On November 25, 2009February 21, 2026 By mspeltoIn Uncategorized

Grasshopper Glacier, the largest is located about 19 km. north of Cook, Montana within Custer National Forest. The glacier on Iceberg Peak occupies a north facing cirque at nearly 3300 m. (11,000 ft.). In 1940, it was about 1.6 km. wide and on its northwest side terminated in a 15-m. cliff. In 1966, seen below, the glacier had an area of 0.42 square kilometers. The name of the glacier is derived from the myriads of grasshoppers that were embedded in the ice. These grasshoppers either were downed by sudden storms or were carried over the glacier by strong air currents, where the cold forced them onto the ice surface. The grasshoppers are an extinct type of Rocky Mountain grasshoppper Melanoplus spretus. They perished here, were buried by new snow and preserved. At the time the glacier ended in a small lake. Progressively the glacier has retreated. By 1966 it was 0.6 km long, in 1994, seen below, 0.36 km long and in 2006 0.27 km long.

In 2005 this glacier has ceased to exist as an active glacier, there are a few remnant perennial snow and ice patches the largest with an area of 0.05 km2. In the majority of recent summers the glacier has lost all of its snowcover. Glacier survival is dependent on consistent accumulation retained on the glacier each summer, this glacier will not survive. The glacier has continued its rapid recession and the further segmentation into small disconnected segments, heralds the end of an active glacier. We do have a gorgeous new alpine lake in its place. Notice the basin is still largely devoid of plant life and the surface still has the color of newly exposed-deposited sediments.

Grasshopper Glacier in 2001 with a few crevasses near the ice front (A.Lussier Image).

Gilkey Glacier Retreat, Juneau Icefield

On November 1, 2009June 30, 2013 By mspeltoIn Glacier Observations

Above is a paired Landsat image from 1984 left and 2013 right indicaing the 3200 m retreat during this period of Gilkey Glacier.The Juneau Icefield Research Program has long monitored the mass balance of the Lemon Creek and Taku Glacier on the Juneau Icefield. This program begun by Maynard Miller in 1946 and continuing through today has also monitored the terminus behavior of the icefields outlet glaciers. Of the 17 significant outlet glaciers 5 have retreated more than 500 m since 1948, 11 more than 1000 m, and one glacier the Taku has advanced. I have a chance to visit the glaciers during a number of summers over the last 25 years as part of this ongoing annual program. The Gilkey Glacier is a 32 km long 245 km2 outlet glacier flowing west from the Juneau Icefield. In 1948 it terminate at the head of a braided outwash plain. At that time it was joined 5 km above the terminus by the Battle and Thiel Glaciers from the south. gilkey 1948 All three of these glaciers drain from the Juneau Iceifeld accumulation zone between 1500 and 2000 m, which maintain consistent snow cover. From 1948 to 1967 the Gilkey Glacier retreated 600 m and in 1961 a proglacial lake began to form. By 2005 Gilkey Glacier had retreated another 3200 m , generating a proglacial lake that is now 3.9 kilometers long, which is approximately the amount of retreat in the last 60 years as well. gilkey 2005 The lake is partly filled with large icebergs from disintegration of the, note below in an image from Scott McGee of JIRP,Gilkey terminus. The lake is currently terminating in this still growing lake. Approximately half of this retreat occurred after a 1991 satellite image indicated the lake was close to half its current size. The retreat has been resulted from calving icebergs into the new lake as well as thinning from melting in the lower reach of the glacier. The extensive debris cover and lack of crevassing in the lower 1500 meters of the glacier indicates that this section is stagnant and will break up soon. Gilkey-Terminus

Gilkey Glacier was in 1955 joined by the tributary glaciers Battle and Thiel Glacier. A visit to the Battle Glacier in 1982 indicated that it had separated from the Gilkey Glacier and the Thiel Glacier, but the Thiel Glacier was still connected. By 1991 the Thiel Glacier had separated. Today these glaciers terminate 3200 m and 1700 m up their respective valleys from Gilkey Glacier. Thiel has retreated 1700 m from the Gilkey Glacier. A retreat of 3200 m has created a glacier 70 % its former length. The vast bare valley beyond the terminus is in stark contrast to the map above. Thiel Glacier has extensive lateral moraines extending above the glacier terminus indicating the ongoing retreat. The lower 3 kilometers of this glacier are flat and are downwasting, indicating a substantial retreat is still underway. A view up the valley from the Gilkey toward the terminus of Battle Glacier indicates that most of the area deglaciated was a flat low elevation valley. Now that the glacier is retreating up a steeper slope, the retreat rate of Battle Glacier should slow. battle terminus

Columbia Glacier year by year

On September 14, 2009June 2, 2011 By mspeltoIn North Cascade Glaciers2 Comments

The following pictures give a year by year view of Columbia Glacier within one day of August 1. The best year was 1999, the worst, 2005.The snowy peaks of the Monte Cristo region can be seen from the Everett area. With 30 glaciers many at low altitudes, this region may receive more snow than any other region in the North Cascades. The largest and lowest is Columbia Glacier occupying a deep cirque above Blanca Lake and ranging in altitude from 4600 to 5700 feet. Kyes, Monte Cristo and Columbia Peak surround the glacier with summits over 2000 feet above the glacier. The Monte Cristo range is the first major rise that weather systems coming off the ocean encounter on the way east to the Cascade Crest. As a result precipitation is heavy. During the summer if it is raining anywhere in the North Cascades it will be in the Monte Cristo region. The glacier is the beneficiary of heavy orographic lifting over the surrounding peaks, and heavy avalanching off the same peaks. We measure the mass balance of this glacier each year and report the data to the World Glacier Monitoring Service. The location is gorgeous as seen in this painting by Jill Pelto Despite the advantages of snow accumulation the glaciers mass balance since 1984 has average -0.5 m a year for a cumulative loss of 13 m. For a glacier that averages 60 m in thickness this is over 20% of its volume. Details of the mass balance research and methods are at

Columbia Glacier has retreated 134 m since 1984. Lateral reduction in glacier width of 95 m in the lower section of the glacier and the reduction in glacier thickness are even more substantial as a percentage. The major issue is that the glacier is thinning as appreciably in the accumulation zone in the upper cirque basin as at the terminus. This indicates a glaciers that is in disequilibrium with current climate and will melt away with a continuation of the current warm conditions. The glacier has lost 17 m in thickness since 1984, but still remains a thick glacier, over 75 meters in the upper basin and will not disappear quickly.

A lateral moraine deposited during the Little Ice Age, is visible at the western edge of the glacier, descending below the glacier to 4250 feet. This moraine has little vegetation on the inside, but is vegetated on the outside. Just in front of the terminus are two terminal moraines deposited during retreat in the last 20 years. Facing southeast Columbia Glacier is protected from any afternoon sun except during the summer. During the winters storm winds sweep from the west across Monte Cristo Pass dropping snow in the lee on Columbia Glacier. Avalanches spilling from the mountains above descend onto and spread across Columbia Glacier. The avalanche fans created by the settled avalanche snows are 20 feet deep even late in the summer. Nearly a third of the glacier is covered by avalanche fans, but no summer avalanches have been observed. Avalanches, shading from the sum provided by the high peaks, and wind drift snow deposition permits Columbia Glacier to exist at such a low altitude.

Devon Ice Cap

On September 12, 2009June 9, 2012 By mspeltoIn Glacier Observations

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.
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. 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 mb In 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