Engabreen Glacier, Norway retreat

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.

Advertisements

6 thoughts on “Engabreen Glacier, Norway retreat

  1. Pingback: Engabreen Glacier, Norway retreat « From a Glaciers Perspective | Today Headlines

  2. Mauri, thanks for this article. What is causing the pulses forward and the retreats? Could the glacier be advancing again somewhere in the future, like it did until 1971, 1984 and 1999?

    • The detailed annual assessments began in 1970. There was strong periods of positive mass balance in 1973-76 and 1981-84. Again from 1989-1997 there was a sequence of positive balance years. You can see from the images during advance the heavy crevassing at the front indicating the vigorous flow. This equates to a rapid response to climate change. Since 1998 there has been a trend of negative balances, thus the glacier is not poised for another pulse. Further the summer melting has been exceptional in 2002, 2003, and 2006. Probably 2010 as well.

  3. I’m sorry, I don’t understand this sentence:

    ” 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.”

    If in the current climate the glacier has a negative mass balance, how can it be said that it will survive the current climatic conditions? Especially given four of the last ten years witnessed “exceptional” summer warming.

    I understand the glacier is healthier than a lot of its fellows, but can you clarify your meaning here a little bit?

    • To survive a glacier needs a persistent and consistent area of accumulation. Engabreen has such an area. The glacier cannot sustain its entire low elevation terminus tongue with current climate. However, retreat has the potential to reduce overall ablation to the point there is a balance.

Comments are closed.