Posts Tagged British Columbia glacier retreat

West Hoboe Glacier Retreat, British Columbia

On the east margin of the Juneau Icefield is a small, compared to other glaciers, 7 km long unnamed valley glacier, here identified as West Hoboe Glacier. Here we use Landsat imagery to identify changes from 1984 to 2013. This glacier is just east of the retreating Hoboe Glacier and Llewellyn Glacier. The glacier flows from 2000 m down to 1250 m and drains into Atlin Lake at the headwaters of the Yukon River. In 2014 the Juneau Icefield research Program is planning to complete field measurements on this glacier for the first time.Atlin bc
Google Earth Image
hoboe view
West Hoboe Glacier is in background of image from the Toby Dittrich led expedition to Mount Service in 2013.

In 1984 West Hoboe Glacier ended at the red arrow below a small cirque glacier south of the glacier. In each image the arrow and letters are in the same location, the pink arrow indicates the 2013 terminus position. Point A indicates a small ice filled basin connected to the West Hoboe Glacier in 1984. The green arrow indicates the junction of the two main arms of the glacier, which has a width of 1100 m. Point B and C are bedrock outcrops in the upper portion of the glacier. By 1993 the glacier has retreated a short distance from the 1984 terminus position, red arrow. By 2004 the glacier has continued to retreat from the 1984 position, red arrow, the tributary glacier junction, green arrow, has been reduced to 900 m. At Point A there is no longer ice in the basin. At Point B the bedrock outcrop exposure has expanded. Both indicate glacier thinning. In 2004 and 2009 snowcover is limited on the glacier. In 2013 a pair of Landsat images, August 1, 2013 and September 2, 2013 indicate that the glacier has retreated 850 m from 1984-2013, now ending at the base of a narrow landslide prone gully. The connection at the green arrow is 800 m, a 300 m reduction in width since 1984. The thinning of the glacier has led to bedrock expansion at Point B and C, this is a 12% reduction in total length. At Point A the separation between the basin and the glacier indicates both marginal retreat and thinning of the glacier. Notice that 70% of the glacier in early September has lost its snowcover. The thinning even at the top of this glacier indicates it will not survive current climate.
hoboe glacier 1984
1984 Landsat image
hoboe glacier 1993
1993 Landsat image
hoboe 8-24-2004
2004 Landsat image
hoboe 8-5-2009
2009 Landsat image
hoboe 8-1-2013
8-1-2013 Landsat image

Hoboe 9-2-2013
9-2-2013 Landsat image

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Bromley Glacier Retreat, NW British Columbia

Bromley Glacier is the largest outlet glacier of the Cambria Icefield near Stewart, BC. The glacier drains north into the Bear River. bromley mapDan Smith and his graduate students of the University of Victoria have been busy searching for fossil wood as it emerges from beneath the rapidly retreating glaciers of British Columbia. They have found numerous pieces from former forest that have emerged in the last decade after being buried for at least 2000 years. Smith, points out this is due to the rapid retreat that began in the area in the 1980′s. Bolch et al (2010) noted a reduction of 0.3% per year in glacier area in the Northern Coast Mountains of British Columbia from 1985 to 2005. Scheifer et al (2007) noted an annual thinning rate of 0.8 meters/year from 1985-1999. One of the glacier they visited was Bromley Glacier in 2011. This led to a publication from Smith and Kira Hoffman (Hoffman and Smith, 2013) that found periods of glacier expansion at ca. 2470–2410, 1850, 1450, and 830 years BP.

Here we examine satellite imagery from 1986, 1997, 2010 and 2013. The yellow, red, and green arrows indicate the same location in each image. In 1986 as in the map the Bromley Glacier was comprised of three large glacier tributaries, two flowing from the east red and pink arrow and from due south. In 1986 the eastern tributaries still contributed directly to Bromley Glacier. The terminus was at the lime green arrow, 500 meters beyond a side valley on the west marked by the yellow arrow. In 1997 the tributary at the red arrow is no longer feeding the Bromley Glacier while the tributary at the pink arrow connection has narrowed. The terminus has retreated 200 m since 1986, but still rounds the bend heading northeast. In 2010 the separation at the red arrow is greater than 1 kilometer. The pink arrow tributary is also no longer in contact with Bromley Glacier. The terminus has retreated to the yellow arrow, a 700 m retreat since 1986. The lower 500 meters of the glacier are narrow and thin. By 2013 the glacier has retreated to the dark green arrow, an additional 500 m since 2010 and 1200 m since 1986. The red tributary has retreated 1400 meters from Bromley Glacier and the pink arrow tributary 250 m from Bromley Glacier.

The loss of contributions from two of the three main tributaries will spur continued extensive retreat of the glacier. The snowline of the main glacier has been at close to 1600 m in the imagery here, too high for anything but a very negative mass balance. This retreat is similar to that of nearby Chickamin Glacier, Porcupine Glacier and Nass Peak Glacier. There is an exceptional photo gallery provided by the Tree Ring Lab at University of Victoria, the album does not get to the Cambria Icefield and Bromley Glacier until image 123, though images 65-68 have excellent examples of fossil trees. Figure 2 from Hoffman and Smith (2013) is below. This is in the area rendered ice free by the retreat of the red arrow tributary since 1986. bromley glacier 1986
1986 Landsat image

bromley glacier 1997
1997 Landsat image

bromley glacier 2010
2010 Landsat Image

bromley glacier 2013
2013 Landsat image

Hoffman and Smith Fgiure 2
Figure 2 from Hoffman and Smith (2013) of red arrow tributary that was connected to Bromley Glacier in 1986, this is a 2011 image.

bromley terminus
Google Earth image 2010

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Nass Peak Glacier Retreat, Coast Mountains, British Columbia

“Nass Peak” Glacier is a 5 km long unnamed valley glacier that feeds Coast Mountain Creek and then Nass River. The closest community is Kitsault, BC on the north side of the small icefield from which the glacier originates. Nass peak map Here we examine changes in the is glacier in Landsat imagery from 1986 to 2013. In 1986 the glacier terminated at the red arrow, this is also approximately the mapped terminus position. The terminus is near the nose of a long ridge at 650 m in 1986. By 1997 the glacier had retreated 800 m to a location adjacent to the southern outlet stream from another glacier in a side valley. By 2010 the glacier has retreated behond the northern outlet stream of the side glacier, pink arrow and almost too the yellow arrow. In 2013 the glacier has retreated just beyond the yellow arrow a distance of 2000 meters since 1986 and is at an elevation of 850 m. For a glacier that was 7.5 km long and is now 5.5 km long that is a 27% loss of length in 27 years. The green arrow point to the separation between a side glacier and the Nass Peak Glacier, this expanded 250 m both from retreat of the side glacier and the lateral thinning at this elevation of Nass Peak Glacier. The last image is a 2009 Google Earth Image indicating the mapped terminus outline to the 2009 terminus.

The Nass Peak Glacier retreat is larger as a percentage of the glacier, but similar in distance than the nearby Porcupine Glacier, BC, Bromley Glacier, BC, Jacobsen Glacier, BC, Chickamin Glacier, AK and Patterson Glacier, AK. Nass Peak Glacier also has lacked a proglacial lake which typically enhances retreat via calving, making the retreat quite significant in terms of surface mass balance loss.
nass peak 1986
1986 Landsat Image

nass peak 1997
1997 Landsat Image

nass peak 2010
2010 Landsat Image

nass peak 2013
2013 Landsat Image

nass peak ge
2009 Google Earth Image

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Toby Glacier Retreat, Purcell Range, British Columbia

Toby Glacier is in the Purcell Mountains of southern British Columbia, part of the Purcell Wilderness Conservancy Park. Here we examine retreat of this glacier from 1998 to 2013 using Landsat imagery and Google Earth images. The map image indicates the Little Ice Age advance moraine (LIA_on other imagers) at 1960 m, a lower lake (LL)at 2060 m, an upper lake (UL) at 2280 m, the former ELA at a slope change at 2500 m and the recent ELA at 2600-2650 m, all images are oriented with north at the bottom. toby map In the 1998 Landsat image the glacier terminates at the yellow arrow 250 m from the Upper Lake. The snowline in 1998 is at 2650 m and only 25% of the glacier is snowcovered. By 2005 in the Google Earth view from 2005 the glacier terminates 450 m from the Upper Lake. In 2013 the glacier terminates 800 m from the Upper Lake, pink arrow. Yellow arrow marks 1988 terminus for comparison. The snowline is again at 2650 m with a month left in the melt season, no more than 20% of the glacier will be snowcovered by the end of the summer. Typically 60% snowcover is necessary for glacier equilibrium. The result of the substantial negative mass balance that result from the high snowlines and small accumulation zone will be continued retreat. There are significant bedrock areas emerging in the upper portion of the glacier indicating a lack of a persistent accumulation zone indicative of a glacier that cannot survive (Pelto, 2010). A glacier lacking a consistent accumulation zone is experiencing a disequilibrium response to climate and cannot retreat to a point of equilibrium. This is exemplified best in an image from Wildair Photography-image 36. The glacier retreat is like that of Vowell Glacier and Conrad Icefield in the nearby Bugaboos. TOBY GLACIER 1998
1998 Landsat image
toby glacier tiltview
2005 Google Earth view

toby glacier ge
2005 Google Earth view

2013 Landsat image

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Vowell Glacier Rapid Retreat, Bugaboos British Columbia

Vowell Glacier is the largest glacier of the Bugaboo’s or maybe was. The glacier drains to the north into Vowell Creek has retreated quite rapidly from 1998 to 2013 creating a new lake and then retreating from that lake. Here we use a sequence of Landsat and Google Earth images to identify the changes from 1998 to 2013. In 1998 Landsat imagery shows the glacier to be 5.5 km long ending at 2060 m with no sign of a lake, this is also the size of the glacier in the BC 20,000 scale topographic map. vowell glacier overview
Vowell Glacier Google earth image from 2005 Pink line map-1998 terminus, green line 2005 terminus, yellow line 2012 terminus.
bugaboo map
Topographic map of Vowell Glacier

vowell glacier 1998 ls
Landsat image from 1998

The pink arrow in each image indicates the 1998 terminus and the yellow arrow the 2013 terminus. By 2005 Google earth imagery indicates a 800 m retreat from the map position and the formation of a proglacial lake with numerous icebergs and residual glacier pieces. The lower 500 m of the glacier is stagnant, uncrevassed and thin at this point. By 2012 Google Earth imagery indicates the glacier has retreated from the lake and is now 1500 m from the mapped position. The 2013 Landsat indicates a terminus retreat in 15 years of 1550 m. vowell glacier map overlay
Mapped extent of glacier overlain in Google Earth

vowell glacier 2005
2005 extent in Google Earth image

vowell map overlay
2012 extent in Google Earth image

vowell glacier terminus 2005
Close up of terminus in 2005

A wonderful image from Canadian Mountain Holidays Heli Ski Guide Lyle Grisedale shows the glacier in 2013. The yellow arrows indicate the current terminus, the burgundy arrows lateral moraines, red arrows glacier peices in the lake and the magenta arrow a detached portion of ice cored moraine.The glacier is flowing with some vigor through the icefall that extends from 2400 m to 2200 m. The lower 400 m of the glacier still appears stagnant and poised for retreat. Worse is the fact that the August 22nd image from 2013, with a month of melting to go, shows the snowline at 2600 m. The snowline will likely rise 200 m by the end of summer leaving only 25% of the glacier snowcovered. A glacier such as the Vowell would need about 60% snowcover to have an equilibrium mass balance for the year. This glacier is retreating more rapidly than the more famously named adjacent Bugaboo Glacier. CMH Bugaboos: Aug 25, 2013

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Galaxy Glacier Rapid Retreat, Pukulkul Basin Glacier disappears, British Columbia

Over the ridge south from Stave Glacier is a 1.5 km long unnamed glacier, that is on the west flank of Galaxy Peak, hence referred to here as Galaxy Glacier. The glacier is in Garibaldi Provinical Park, British Columbia. galaxy areaKoch et al (2009) in their detailed survey of glaciers in the park chronicled the Park’s glacier retreat from 1952 to 2002. Koch et al (2009) Found that all 45 glaciers are retreating, and Stave Glacier was experiencing its fastest retreat from 1976-1996, with a 750 m retreat. Satellite imagery from 2012 indicates the Stave Glacier retreat rate from 1996 to 2012 is 1600 m or 100 m per year, even faster. Here we utilize Landsat imagery from 1985, 1987, 1992 and 2009, plus Google Earth imagery form 2006 to examine the retreat and separation of Galaxy Glacier. The orange arrow indicates the terminus of the Galaxy Glacier (G) in 1985 where it joined the glacier (P) in the Pukulkul Basin where several lakes have been forming. This basin is just north of Pukulkul Peak. In 1985 Galaxy Glacier and the Pukulkul Basin Glacier are joined at the orange arrow, the red arrow marks the 2009 terminus and the purple arrow indicates the connection to the highest accumulation area on the east slope of Corbold Peak. By 1987 Galaxy Glacier has separated from the Pukulkul Basin Glacier, the latter has an area of 0.45 square kilometers and is larger than the lake it ends in. By 1992 the Galaxy Glacier is separated by 500 meters from Pukulkul Basin Glacier. The area of bare rock at the purple arrow at the top of Galaxy Glacier has expanded. By 2006 the Pukulkul Basin Glacier is gone and a 2.5 km long series of lakes is in its place. Galaxy Glacier has retreated 800 m from the new lake, and 650 meters from its 1985 position. The purple arrow indicates two large rock outcrops effectively ending significant glacier inflow from the upper east slopes of Corbold Peak. By 2009 the Pukulkul Basin Lake has a deeper blue as the glacier input has declined. The glacier is 90% bare of snowcover and the bedrock at the purple arrow has continued to expand. A closeup of the glacier from the 2006 Google Earth imagery indicates exposed firn layers at the blue arrows. This indicates that all the snowcover not just from the most recent winter has been lost but a number of previous winters as well. This is indicative of a glacier that has no consistent accumulation zone and cannot survive (Pelto, 2010). This glacier similar to the nearby Helm Glacier cannot survive current climate. The purple arrows indicate the limited connection to the upper slopes of Corbold Peak. The red arrow indicates the current terminus position. Galaxy Glacier has lost half of its area in the last 25 years, and the 800 m retreat is one-third of its total length. galaxy glacier 1985
1985 Landsat

galaxy glacier 1987
1987 Landsat

galaxy glacier 1992
1992 Landsat

galaxy glacier 2006
2006 Google Earth

galaxy glacier 2009
2009 Landsat

galaxy glacier closeup
2006 Google Earth Cloesup

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Stave Glacier Retreat, British Columbia

Stave Glacier is a six kilometer long valley glacier in Garibaldi Provinical Park, British Columbia. Koch et al (2009) in their detailed survey of glaciers in the park chronicled the glacier’s retreat from 1952 to 1996. Here we update the changes in Stave Glacier to 2012. Koch et al (2009) completed a map, first image that indicates the retreat rate of the glacier as 26 meters/year from 1900-1952, 33 meters/year 1952-1977 and 53 meters/year from 1977 to 1996. Examined below is Google Earth imagery from 2006, aerial photography from 2009 and Landsat imagery from 2009 and 2012. The Google Earth image indicates the terminus position using arrows in 1952 (yellow arrow), 1977 (pink arrow), 1996 (orange arrow), 2006 (blue arrow) and 2012 (purple arrow). In the Landsat images the same color scheme is used, for terminus front lines also. The retreat from 1996-2012 is 1600 meters, 100 meters/year. This glacier is still not approaching equilibrium as the accelerating retreat indicates. stave mapstave ge
stave 2009
stave 2012 A close up of the terminus in 2006 (top) and 2009 (bottom) indicates the lowest couple hundred meters is thin and uncrevassed indicating retreat will continue. The glacier terminus is at 1275 meters today. There is an active icefall above the terminus at 1500 meters, the snowline has been at 1900 meters. Unlike the nearby Helm Glacier, Stave Glacier has a persistent accumulation zone and can survive current climate. Its behavior is similar to that of Warren Glacier. stave 2006 terminusstave terminus

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Jacobsen Glacier, BC Retreat

Jacobsen Glacier is part of the Monarch Icefield of the Coastal Range of British Columbia. VanLooy and Forster (2008) noted that the glacier retreated at a rate of 30 meters/year from 1974 to 1992 and 47 meters/year from 1992-2000. In this post we examine Landsat satellite imagery from 1992, 1994, 2010 and 2012 to illustrate the changes over the last two decades. There are three readily observable changes. The first, indicated by purple arrows, is the lateral recession 2.5 km upglacier of the current terminus. At this point the glacier was in contract with a proglacial lake. The lake shoreline has not changed from the 1992-1994 images, but the glacier margin is now 300 meters distant from the lake margin. The second change, indicated by yellow arrows, is of what was previously a secondary terminus that terminated in a small proglacial lake in 1992-1994. This small lake has turned into an embayment of the larger unnamed lake that the Jacobsen Glacier ends in. The secondary terminus has retreated 900 meters since 1992. The last change is the actual terminus retreat of Jacobsen glacier with the 1992 terminus indicated by the pink arrows and the 2012 terminus by the blue arrow on the northern margin. The retreat and lake expansion has been 1100 mters from 1992-2012, a rate of 55 meters/year, only a slight change from the 1990-2000 reported rate. The changes indicate a consistent mass balance loss that is typical of glaciers in the Coast Range from Lemon Creek Glacier to Bridge Glacier and Helm Glacier. The ongoing mass balance losses are resulting in substantial glacier area and volume losses ( Pelto, 2007; Scheifer et al, 2008).

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Washmawapta Glacier Retreat, British Columbia

The West Washmawapta Glacier and Washmawapta Icefield are located in the Vermillon Range in British Columbia. They are in a basin between Limestone Peak and Helmet Peak. The West Washmawapta is a cirque glacier and has been the focus of detailed studies of its dynamics and runoff in recent years. The study of its dynamics (Sanders et al, 2010) measured velocities of 3-10 meters/year, pretty typical for a cirque glacier of this size, and had a maximum depth of 185 m, a bit deeper than usual. The runoff study (McGregor, 2007) and Dow et al (2011)examined streamflow below the glacier and found that peak flow was at 2100 hours, several hours after peak melting. They conclude that this indicates a well developed subglacial drainage system. Sanders et al (2010) noted that West Washmawapta Glacier lost 30% of its area from 1949-2007. A comparison of Google Earth imagery from 2002 (top) and 2007 (middle) and Landsat imagery from 2009(bottom) identifies changes in the two glacier in the last decade. For the West Washmawapta Glacier in 2002 the glacier ended in contact with two proglacial lakes (Point A-C) and a lake that is just forming at Point B. The retreat is from 30-50 meters in this five year span. In the 2009 Landsat the Lake at Point C is well separated from the glacier. For Washmawapta Icefield, does not really deserve the icefield title, has lost a lower former glacier section that was in contact with Elizajan Lake, green arrow. The purple areas point to two prominent bedrock features that indicate retreat of 30 meters over the five year time span. The problem for both glacier is the insufficient size of the accumulation area. In 2009 the image is from August 20th, a month left in the melt season and only 40% of the glaciers are snowcovered. An alpine glacier like these needs at least 55% snowcover to be in equilibrium. The 2007 imagery in from July and the accumulation area is at 65%, by September of 2007 the extent was down to 35%. Now if you are still not sated, the video on the West Washmawapta Glacier project illustrates the amount of hard work and good humor that is essential to complete such a field project is quite a treat.

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Apex Glacier Retreat British Columbia

The Apex Glacier is part of the Clemenceau Icefield Group in the Rocky Mountains of British Columbia. The Apex Glacier drains into 430 square kilometer Kinbasket Lake impounded by the 1.75 MW Mica Dam. In a recent paper Jiskoot et al (2009) examined the behavior of glacier in this and the neigboring Chaba Icefield. They found that from the mid 1980′s to 2001 the Clemenceau Icefield glaciers had lost 42 square kilometers, or 14% of their area. During this same period terminus retreat averaged 21 meters per year on the glaciers. In this post we are looking just at Apex Glacier contrasting the mapped extent, 2001 extent and 2010 extent in a Landsat image. A new glacier lake began to form after the 1980′s mapped extent. In the images below the 1980′s terminus is marked with a green line, the 2001 extent in magenta. By 2001 in the Google Earth image the lake is 0.5 km long, in 2010 the lake is 0.8 km long. Apex Glacier’s retreat of 300 m in nine years exceeds 30 meters per year. Hester Jiskoot’s (University of Lethbridge, Alberta) found a retreat rate of 52 meters per year from 1986-2001. The reduced rate of retreat may result from the lake depth being reduced, that the lake is getting a bit narrower hints at this as well. One other interesting aspect is that this glacier is fed by a northern and a southern accumulation zone. The snowline is 2400 to 2500 meters in the 2010 August Landsat image. The remaining accumulation zone is quite small for the northern accumulation zone even with another month of melting to go. The ablation zone is between the purple margin and burgundy snowline. The accumulation zone is between the snowline and the green upper limit of the glacier, with the bare rock areas noted with the tan line. The result for Kinbasket Lake of the loss of the collective large area is a reduction in summer glacier melt and summer glacier runoff. The annual runoff which will be dominated by annual precipitation would not change just because of the glacier loss as noted in cases like the Skykomish Basin (Pelto, 2011) and Bridge River(Stahl et al 2008).

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Bridge Glacier Retreat Acceleration, BC, Canada

Bridge Glacier is an 17 km long outlet glacier of the Lilloet Icefield in British Columbia. The glacier ends in a rapidly expanding glacial lake with 1100 meters of retreat from 2005-2010. This 200+ m per year retreat is a substantial acceleration over the observed retreat rate of 30 m per year from 1981-2005 by Allen and Smith (2007). They examined the dendrolchronology of Holocene advances of the glacier and found up to 2005 a 3.3 kilometer advance from the primary terminal moraine band, with the most extensive advances being early in the Little Ice Age. The glacier currently ends at 1400 m and in 2010 had a late summer snowline of 2000 m. . The glacier terminus in 1970 is shown in map form, and is indicated by a brown line. The 2003 terminus position from a Landsat image, second image, is next with a red line marking the terminus. The normal Google Earth image, third image, is from 2005 and has a green line. An image from Geoeye from August 2010, last image, terminus purple line indicates the rapid acceleration of retreat. Retreat from 1970-2003 was 48 m per year. The retreat from 2003 to 2010 is 1400 meters, 200 m per year. This continued retreat and area loss will lead to glacier runoff decline in summer. This is crucial to the large Bridge River Hydro complex. This complex managed by BC Hydro can produce 490 MW of power. Stahl et al (2008) note in their modeling study of the glacier that ,”The model results revealed that Bridge Glacier is significantly out of equilibrium with the current climate, and even when a continuation of current climate is assumed, the glacier decreases in area by 20% over the next 50 to100 years. This retreat is accompanied by a similar decreasein summer streamflow.” This parallels our findings on the Skykomish River in the North Cascades, Washington Pelto (2008) and Pelto (2011).

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Warren Glacier Retreat, British Columbia, Canada

Warren Glacier in Garibaldi Provincial Park, British Columbia, Canada terminus retreat has been observed for over a century. A period of extensive retreat from 1890-1964 was followed by a period of minor advance from 1973-1977, and then rapid retreat from 1977-2009. Johannes Koch has documented this retreat in the map below and with the historic images as well, the work has been published with less colorful graphics (Koch et al., 2009).
. When I first saw the glacier in 1986 it had just retreated from the edge of the lake. By 2003 as seen in the somewhat blurry satellite image below, the glacier was 310 meters from the lake edge. In the 2009 Google Earth image the glacier is 500 meters from the lake edge. The rate of retreat over the 25 year period is 20 meters per year. The rate of retreat has again increased from 2003-2009, being 32 meters/year. The upper section of the glacier has unlike nearby Helm Glacier maintained some snow covered areas even in poor snow summers such as 2005 and 2009. This suggests the glacier can survive current climate with further retreat. The average thinning of Warren Glacier is similar to that of Helm, Sphinx and Sentinel Glacier at nearly 50 meters since 1928, note Figure 14 (Koch et al. 2009). This thinning due to ongoing negative mass balance has led to a 50% reduction in area since 1928. The large area loss as a percentage reflects the large relatively flat low lying basin now occupied by the lake.

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