From a Glaciers Perspective

Qinngua Avannarleq Retreat, Southwest Greenland

June 13, 2013 at 4:40 pm · Filed under Glacier Observations ·Tagged evighedsfjorden glacier retreat, Qinngua Avannarleq retreat, Sukkertoppen ice cap retreat

Qinngua Avannarleq is at the head of Evighfjorden an arm of Kangerlussuatsiaq Fjord in southwest Greenland. Leclercq et al (2012) notes the glacier is 15 km long and has an area of 57 square kilometers. They further note that the glacier retreated 0.5 km from 1850-1960. Here we examine Landsat imagery from 1996, 2000, 2009, 20011 and 2012. In each image the yellow arrow points to a tributary from the northeast that met the glacier at the terminus in 1996, the red arrow indicates the 2012 terminus location and Points A-D identify locations where bedrock exposure is expanding with glacier thinning. In 1996 and 2000 the terminus was 1.8 km wide and merged with a tributary from the north right at the terminus. In 1996 and 2000 Point C and D are uninterrupted glacier cover. At Point A and B there are narrow glacier tongues passing between rock exposures. By 2011 and 2012 the terminus has retreated 1.3 km from the 1996 position. At Point A the tributary that separated the rock outcrops has now disappeared leaving uninterrupted rock. At Point B the bedrock area has expanded and the narrow tributary no longer connects to the main glacier. At Point C a ridge of bedrock has extended 1 km further into the ice cap. At Point D a new bedrock knob has emerged amidst the main glacier. The retreat of over 1 km since 1996 is a greater retreat than had occurred from 1850-1990 (Leclerq et al (2012). The retreat of this glacier is similar to that of Narssap Sermia Glacier and Qaleriq Glacier. A nunatak 12 km inland also indicates thinning with a stranded section of ice, red arrows. This area also features very dirty ice, black arrows, that increases the albedo, which bring to mind the Dark Snow Project.
1996 Landsat Image

2000 Landsat Image

2009 Landsat Image

2011 Landsat image

2012 Landsat image

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Canada Glacier Retreat Post Index

June 12, 2013 at 11:44 am · Filed under Glacier Observations ·Tagged Canada glacier retreat list, canadian glacier retreat index

Canada Glacier Index
Canada has more than 20,000 glaciers spread across its arctic islands and in the mountains of the western provinces. Below is a list of 32 glaciers in Canada that are all retreating and chronicled glacier by glacier. I have had the pleasure of working on 10 Canadian glaciers.

Great Glacier, National Railroad Archive 1914 image.

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Neve Glacier Retreat, North Cascades, Washington

June 10, 2013 at 12:22 pm · Filed under Glacier Observations ·Tagged neve glacier retreat, north cascade glacier melt, north cascade glacier retreat

I have had the opportunity to visit the Neve Glacier on eight occasions, it is not easy to get to. In the North Cascades it is one of a handful of glaciers with a large higher elevation accumulation zone, that is not on a volcano. The glacier feeds Diablo Lake, part of the Skagit River hydropower system. The terminus of the glacier in 1975 was in basin that receives considerable avalanche deposition slowing the retreat. In this post we focus on the thinning of the glacier leading to expansion of bedrock exposures at four locations above the former terminus, that by 2011 had led to this low lying basin being dynamically cutoff from the upper glacier. In each image the red letters A-D are located in the same spot, and the purple arrow on the Google Earth images indicates the terminus position. The first image is an aerial view of the glacier from Austin Post, USGS from 1975: at point A there is a quite small exposure of bedrock, at Point B and C there is a good connection of feeder glaciers from the higher slopes to the main valley glacier. At Point D there is continuous glacier cover. This was the case during my first two visits to the glacier in 1985 and 1988, second image. The third image is from 1990 and reflects limted change from 1975 as well, the blue arrows indicate glacier flow.

: 1975 Neve Glacier-Austin Post

: 1988 Neve Glacier

: 1990 Neve Glacier-Google Earth

. By 1996 notable thinning of the glacier was apparent adjacent to Point A, in 2001 and 2002 the thin nature of the ice around the bedrock at Point A is evident.

: Nev Glacier adjacent to Point A 1996

: Neve Glacier 2001

: Neve Glacier 2001

. The accumulation zone of the glacier around Point B and D in 2001 indicates no bedrock exposure at D and a connection of the upper glacier at Point B; however at Point D in 2009 the large new bedrock areas that have resulted from thinning has occurred.

: Neve Glacier main trunk 2001

: Neve Glacier accumulation zone 2001

: Neve Glacier 2009 Accumulation zone

A comparison of the Google Earth imagery from 1990, 2006 and 2009 indicate the expanding bedrock at each Point. A closeup of Point A from 2009 has the bedrock delineated with red dots indicating that the left arm of the glacier that formerly encircled Point A, now ends above Point A and that the right hand arm is only 35 m wide and despite the steep slope has no crevassing and is stagnant. At Point B the upper glacier no longer reaches the main trunk. At Point C the connection to the main glacier has decreased by 50% in its width from 140 m to 70 m, and at Point D several large bedrock areas have emerged.

: 1990 Neve Glacier-Google Earth

: 2006 Neve Glacier-Google Earth

: 2009 Neve Glacier-Google Earth

: 2009 Bedrock area at Point A

In 2013 or 2014 the upper glacier will likely separate from the former terminus region below the Point A bedrock region. The thinning of this glacier is typical of North Cascade glaciers (Pelto, 2007), though the retreat has been unusually small (Pelto, 2010).

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Excelsior Glacier Retreat, Alaska

June 6, 2013 at 11:22 am · Filed under Glacier Observations ·Tagged excelsior glacier retreat

Excelsior Glacier in Alaska has terminated in a lake for the last century. Here we examine the retreat of this glacier from 1984 to 2011 using Landsat imagery. This glacier is seen as a model for the impending retreat of Brady Glacier examined in a paper we just published (Pelto et al, 2013). In 1909 the glacier ended on the strip of forested land between the lake and the ocean (Molnia, 2007). By 1950 the glacier had retreated 2 km from this strip of land creating the new lake (USGS-Molnia, 2008) In 1909 the glacier had ended on land at the south end of the lake, indicating a retreat of 4.5-5.0 km in approximately a 75 year period. In 1984 (first image below) Excelsior Glacier ended at the pink arrow and the lake extending beyond the terminus was 4.7 km long, the yellow arrow indicates the 2011 position and just south (under) the arrow is a glacier dammed lake. The lake width has changed little and is 1.4-1.8 km wide in the region the terminus has been retreating through during the last 30 years. By 1989 the glacier had retreated 500 m and the lake was filled with numerous icebergs. By 2001 the glacier had retreated 1500-1700 m from the 1984 position, a rate of 100 meters per year, and the glacier dammed lake south of the yellow arrow is still apparent, as are a couple of large icebergs. The 2003 Google Earth image indicates further retreat and again a couple of large icebergs and a large crack near the center of the terminus indicating a new iceberg getting ready to separate. By 2011 the glacier had retreated past the formerly glacier dammed lake and ended at the prominent ridge just north of this former lake and the new inlet that replaces it. The glacier has retreated 3400-3700 m depending where on the front the measurement is made. This is a rate of over 100 meters per year since 1984.
Another big change is the thinning and narrowing of the tributary entering on the east side of the glacier north of the terminus. This is illustrated in the last image with a combined 1989 image left and 2011 rigth and the red arrows pointing out three significant points of thinning and new rock-moraine exposure. This glacier has behaved in a similar fashion to so many Alaskan glacier from the nearby Bear Glacier, to British Columbia’s Melbern Glacieror Porcupine Glacier and southeast Alaska’s Chickamin and Norris Glaciers of southeast Alaska

1984 Landsat Image

1989 Landsat image

2001 Landsat image

2003 Google Earth image

2011 Landsat Image

1989-2011 Landsat image

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Zayul Chu Headwaters Glacier Retreat, Tibet, China

June 3, 2013 at 12:57 pm · Filed under Glacier Observations ·Tagged hydropower glacier runoff, lohit hydropower glaciers, zayul chu glacier runoff hydropower, zayul chu headwater glaciers

The headwaters of the Zayul Chu River is a series of glaciers. This river becomes the Lohit River as it enters India. The impact of glaciers is visible just from the color of the water, the greenish tone being generated from glacier flour. The Lohit River is also the focus on a hydropower development plan that proposes six dams that would generate 7450 MW.

Glaciers at the Headwater of Zayul Chu noted by red, yellow and purple arrows.

Map of proposed Hydropower Project for Lohit River, yellow arrows indicate dams.

Table of hydropower characteristics for six proposed sites on Lohit River.

Lohit River, color indicates glacier contribution

Here we examine three glaciers that have seen lake expansion at the terminus in the last 25 years using satellite imagery from 1987, 1996, 2009 and 2011. In 1987 there was no lake at the end of the glacier ending at the purple arrow. In 1987 the glacier ending at the red arrow, ended in a narrow lake. At the yellow arrow the glacier ended in a small round lake in 1987. By 1996 the glacier at the red arrow has retreated leading to a lake that is 100 m longer than a decade before. The glacier at the yellow arrow has pulled from the lake it had ended in. In 2009 a small lake has formed at the end of the glacier with the purple arrow, a distance of 200 m. The glacier at the red arrow has retreated from the lake it had formerly ended in, a distance of 400 m. The glacier at the yellow arrow has retreated 200 m from the lake it had ended in. Each of these glaciers ends between 4200 and 4600 m and begins above 5300 m. The glaciers retain snowpack on the upper reaches each summer and will continue to retreat but can survive current climate. The retreat of the Zayul Chu headwaters glaciers parallels those of the Bode Zangbo Headwaters a short distance to the north and the Hkakabo Razi Glaciers a short distance south.

1987 Landsat image

1996 Landsat image

2009 Landsat image

2011 Landsat image

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Hkakabo Razi Glacier Retreat, Myanmar and China Border

May 30, 2013 at 10:43 am · Filed under Glacier Observations ·Tagged hkakabo Razi glacier retreat, irrawaddy river glacier retreat, Myanmar glacier melt, Myanmar glacier retreat

Hkakabo Razi is the highest peak in Myanmar and straddles the border with China. The Myanmar side (east) of the mountain drains into the Irrawaddy River and on the China side (west) to the Brahmaputra River. First of all how many people thought Myanmar had glaciers? Secondly this is a remote peak that only one party has managed to climb. In the Google Earth image the blue arrows indicate icefall regions and the direction of flow into these areas. Here we examine the changes in several glaciers using Landsat imagery from 1987, 1996 and 2009. The red arrows indicate several locations in each image where in 1987 and 1996 sections of a each glacier coalesce. By 2009 in each of the red arrow locations the sections of the glacier have separated. The change in terminus position of three glaciers is also noted, the yellow dot indicates the terminus of the main west flowing glacier. The retreat from 1996 to 2009 is 250 m. The green dot indicates a location at the terminus of an east side glacier. In 1996 the terminus is at the down slope side of the dot and in 2009 the terminus barely reaches the up slope side of the green dot a retreat of 200 m. The pink arrow indicates the terminus of a steep east side glacier. In 1996 the glacier ended at a prominent cleft in the rock, pink arrow and by 2009 had retreated 200 m from this feature. These glaciers have behaved in a similar fashion to Hailuogou Glacier and the glaciers at the headwater of the Bode Zangbo.
1987 Landsat image

1996 Landsat image

2009 Landsat image

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Bode Zangbo Headwaters Glacier Retreat, Tibet, China

May 27, 2013 at 11:10 am · Filed under Glacier Observations ·Tagged Bode Zangbo glacier retreat, Parlung Zangbo glacier retreat, Yarlung Tsanpo headwaters glacier retreat

In the eastern portion of the Nyainqêntanglha Shan, there is a raindrop shaped group of mountains encircled by the Bode Zangbo to the west and Yu Chu Zangbo (maps indicate several names here) to the the east. At the headwater of the Bode Zangbo are a series of glaciers ending in valley occupied by several new lakes formed by glacier retreat. The Bode Zangbo is the site of a proposed new 9600 kW hydropower project financed by Datang Power International. The Bode Tsangbo than joins the Parlung Zangbo and then Yarlung Tsangpo that becomes the Brahmaputra River in India. Both of the latter rivers are the focus of ongoing intensive hydropower development as indicated by the map from Tashi Tsering, with most existing dams being upstream on the Yarlung, red arrow indicates glacier site. Here we focus on two glaciers in particular indicated by a red and yellow arrow in each Landsat or Google Earth image. Both glaciers are unnamed. In fact the first image is the area in general from Google Earth with all the layers activate to show names, and there are none in this mountain region. In the lower left of the image China National Road 318 is visible that in this region connects Bomê County and Nyingchi.

The red arrow indicates a glacier that was 3 km long in 1986 beginning at 5500 m and ending at a moraine at 4900 m. The red arrow points to the low lying terminus piedmont lobe. The second glacier ends in a lake, with the yellow arrow indicating a peninsula on the northeast side of the lake where the glacier ends in 1986. The blue arrow simply indicates the drainage direction of the stream. In 1986 the Bode Zangbo Headwaters Glaciers at the red arrow has no lake at its terminus, the terminus has a toe that turns south down the main valley to end at a series of moraines. By 1999 a tiny lake is evident. In 2000 and the 2001 Google Earth image the lake is still barely detectable. By 2011 a full fledged deep blue lake has developed, where the terminus of the glacier had been. The lake is 600 m long and 400 m long, indicating a 550-600 m retreat in the last decade of the glacier. At the yellow arrow there is limited change from 1986 to 2000, with the glacier still ending in proximity to the peninsula. By 2011 the glacier has retreated 350 m from the 1986 position. The other glaciers in the valley have also been in retreat, but given the location of the scan line errors and clouds it is harder to point out the specific retreat. The yellow dots in the late summer 2011 image indicates the snowline at 5150 m. This is the same snowline and terminus behavior as noted for Jiongla Glacier 110 km west northwest. The glacier follows the pattern of many other glaciers retreating in the region leading to lake expansion, Longbasba Glacier.

1986 Landsat Image

1999 Landsat Image

2000 Landsat Image

2001 Google Earth Image

2011 Landsat Image

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From a Glaciers Perspective

Qinngua Avannarleq Retreat, Southwest Greenland

Canada Glacier Retreat Post Index

Neve Glacier Retreat, North Cascades, Washington

Excelsior Glacier Retreat, Alaska

Zayul Chu Headwaters Glacier Retreat, Tibet, China

Hkakabo Razi Glacier Retreat, Myanmar and China Border

Bode Zangbo Headwaters Glacier Retreat, Tibet, China

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