Tag: svartisen glacier retreat

Flatisen Glacier, Norway Retreats from Lake & Separates

On By mspeltoIn Norway glacier retreat

Flatisen Glacier in Landsat images from 1990 and 2018.  The glacier terminates in the proglacial lake in 1990 at the red arrow and in 2018 at the yellow arrow no longer terminating in the lake.  The pink arrows indicate three connections of the ice cap to the terminus tongue in 1990, with two lost by 2018. 

Flatisen is the primary outlet glacier on the southern side of the second largest ice cap in Norway the Western Svartisen. From 1945-2000 the glacier terminated in a proglacial lake that expanded from 1.5 km long in 1945, to 3 km in 1985 (Theakstone, 1990) to km in 2000.  Haug et al (2009)  indicate significant mass loss of the Western Svartisen Ice Cap from 1985-2000.

In 1990 the glacier terminated in the proglacial lake that was ~3.5 km long.  There were significant feeders from the ice cap both north and south of the terminus tongue, pink arrows. In 1999 the glacier has retreated several hundred meters, still terminates in the lake and is still connected to the ice cap at the three noted locations, pink arrows.  By 2014 the glacier has retreated out of the lake and has lost the two eastern connections from the ice cap to the terminus tongue.  There is not retained snowcover on the valley tongue of the glacier.  By 2018 the glacier has retreated 1400 m from the 1990 position, has only one narrow connection to the main ice cap to the north and has very limited retained snowpack even on 8/6/2018.  There will be continued large mass balance loss for this glacier in 2018 reflective of the warm melt season in Norway. Once the glacier connection entering from the northwest is lost the glacier will have a limited accumulation zone.  The retreat of this glacier is greater given the size of the glacier than at two other key glaciers of the ice cap, Engabreen and Storglombreen.

 

Flatisen Glacier in Landsat images from 1990 and 2018.  The glacier terminates in the proglacial lake in 1990 at the red arrow and in 2018 at the yellow arrow no longer terminating in the lake.  The pink arrows indicate three connections of the ice cap to the terminus tongue in 1990, with two lost by 2018.

Map of Flatisen Glacier from the Norway Glacier Atlas indicating the margin in 1990 dark green and 1999 light green.

Storglombreen Glacier Loss, Norway

On By mspeltoIn glacier climate change, Glacier Observations, Norway glacier retreat1 Comment

storg compare Landsat

Landsat images from 199, 2002 and 2016 comparing glaciers draining into Storglomvatnet.  Red arrows indicate 1999 terminus locations, purple dots the snowline. 

Storglomvatnet has several glacier that terminated in the lake in 1999, Storglombreen Nord, Sorglombreen Sud and Tretten. This lake is the main reservoir, 3.5 billion cubic meters that feeds the 350 MW Svartisen Hydropower plant. The lake has an elevation of 585 m, while the power plant is at sea level. Paul and Andreassen,(2009)  examined glacier area and found overall almost no areal extent change from 1968-1999 of Svartisen region glaciers, including the three examined here.  Engelhardt et al (2013), note this was due to positive trends of winter balance between 1961 and 2000, which have been followed by a remarkable decrease in both summer and winter balances leading to an average annual balance of –0.86±0.15 m w.e.a–1 between 2000 and 2010 .Since 1999 there have been changes. The Norwegian Glacier Inventory  and the online digital atlas use this 1999 imagery and indicate glacier area  for Storglombreen Sud at 15.9 km2, for Storglombreen Nord  at 41.2 km2 and Tretten-nulltobreen at 5.9 km2.

In 1999 each of the glaciers reaches the lake shore at 585 m in four separate terminus fronts. The snowline in 1999 is at 1150 m. In early August 2002 the termini still reach the lake shore and the snowline is higher at 1250 m.  In 2001, 2002 and 2003 mass balance measurements by the Norwegian Water Resources and Energy Directorate, indicate the snowline reached the top of the glacier at 1580 m. In 2016 the glacier termini no longer reach the lake shore and the snowline is again at 1150 m. It is evident in the Landsat image above that Storglombreen Sud and Tretten-nulltobreen no longer reach the lake shore, the southern most and northern most termini and arrows.  The two termini of Storglombreen Nord no longer reach the lake, though this requires higher resolution Sentinel 2 images to illustrate. Retreat of Tretten-nulltobreen from 1999-2016 has been 200 m, of Storglombreen Sud 250 m and of Storglmbreen Nord 100-200 m. There was limited calving into the lake and the retreat from the lake will not significantly alter the retreat rate of the glacier.  The high snowlines of recent years will lead to continued retreat. The retreat here is much less than on Engabreen which shares a divide with Storglombreen Nord, Flatisen  or Blåmannsisen.

svartisen west

Map of the glaciers in the region from the Norwegian Glacier Inventory online map application, based on 1999 images.

storg 2016 sentinel

Sentinel 2 image of the glaciers of Storglomvatnet from August 2016.  Notice that none of the termini reach the lake shore. 

 

 

 

 

 

 

Winsvold, Andreassen and Kienholz (2014)

Engabreen Glacier, Norway retreat

On By mspeltoIn Glacier Observations6 Comments

Engabreen is an outlet glacier of the Svartisen ice cap in northern Norway. It has an area of 40 km2. Most of the area lies between 1200 and 1450 m the high plateau of the ice cap. This glacier has been the focus of attention from the Norwegian Water Resources and Energy Directorate (NVE) for over 50 years. NVE maintains the most extensive and detailed glacier monitoring network in the world. The NVE annual mass balance measurements on Engabreen indicate that winter snow typically accumulate 3 m of water equivalent on the ice cap. This amounts to 5-7 m of snowpack as the melt season begins in May. The glacier terminus descends from the ice cap down nearly to Engabrevatnet, a lake at 7 m. At the terminus annual melting is 12 m.
The rivers from the northern and eastern side of Svartisen were regulated in the 1990’s for hydro power production by construction of a tunnel system partly underneath the glacier. Today about 60% of the potential runoff of the Engabreen is captured and sent through a bedrock tunnel to the hydropower facility. During completion of this tunnel access to the glacier base was opened. Today there is the world’s only ongoing subglacial laboratory here. The melt water from Engabreen is collected into this tunnel system at 620 m a.s.l. underneath 200 m of glacier ice in the ice fall.
Late in the 18th century Engabrevatnet started to appear as the glacier retreated upvalley.
In 1903 regular length change observations were initiated, a small advance ensued until 1910. By 1931 the glacier retreated 100 meters, and the glacier tongue was thinning. During the next decade calving led to rapid retreat revealing the rest of Engabrevatnet. The retreat ended in 1965, since then has advanced with three different pulses ending in 1971, 1984 and 1999, the last pulse reaching to within a few meters of the lake shore. From 1999-2009 Engabreen has retreated 255 m. Below are pictures from the NVE taken in 2000 and 2008 of Engabreen, note the large contraction of the terminus area. Also note the considerable reduction in crevassing at the terminus, indicating a velocity reduction and that retreat will continue in the near future. The 2009 position is its point of furthest retreat since the Little Ice Age. The recent retreat indicates a recent trend of negative mass balance on the glacier. There is excellent flow off the ice cap that has persistent and consistent snowcover indicating this glacier will survive current climate.