tasermiut fjord glacier retreat – From a Glaciers Perspective

Landsat image sequence from 1999-2016. Red arrows mark the 1999 terminus, yellow arrows the 2016 terminus and the purple arrow a tributary that detaches from Semitsiaq (S). Tasermiut Sermeq (T) retreats from the fjord.

Tasermuit Fjord in southern Greenland is noted for its beauty, and until recently the fjord terminated at a glacier front. Currently no glacier reaches to the fjord. The retreat over the last two decades is similar to neighboring glaciers Kangersuneq Qingordleq and Qaleriq. The loss of direct glacier connection is also occurring at Alangordlia. Here we examine Landsat images from 1999-2016 to observe glacier change. At the head of the fjord is Sermeq Tasermiut and on the east side is Sermitsiaq.

In 1999 the Sermitsiaq Glacier terminated at the eastern end of a small lake, red arrow. Tasermiut Sermeq terminated in the fjord, red arrow. By 2002 Sermitsiaq had retreated from the lake, while Tasermiut Sermeq still reached the fjord. In 2013 Tasermiut Sermeq had retreated from the fjord and Sermitsiaq had retreated substantially from the lake and also had a significant tributary from the north detach, purple arrow. In 2016 Sermitsiaq has retreated 700 m since 1999, yellow arrow. Biggs (2011) had noted a 610 m retreat of the glacier from 1987-2009, a slower rate than since 1999. Tasermiut Sermeq has retreated 300 m since 1999,and has a narrow steep tongue that will melt back quickly in the near future.

Murray et al (2015) examined 199 tidewater glaciers in Greenland and noted significant retreat of 188 of them. This is changing fjord dynamics, which will in the case of Tasermiut affect the marine biology, which has not been studied in any detail yet. Students on Ice 2014 Arctic Expedition provides exceptional imagery of this fjord and the Nanotarlik region.

Google Earth imagery of the region. illustrating the loss of fjord connection after 2009.

Map of the region

Qaleraliq Glacier is in southern Greenland and flows into the Tasermiut Fjord. Glaciers in this region have experienced substantial retreat since 1990 Weidick et al (2012) and Howat and Eddy (2011). Howat and Eddy (2011) state that, “We find that 90% of the observed glaciers retreated between 2000 and 2010, with rapid retreat observed in all sectors of the ice sheet. The current retreat is accelerating and likely began between 1992 and 2000, coincident with the onset of warming, following glacier stability and minor advance during a mid-century cooling period.” In this case we are examining a tidewater glacier in Southern Greenland using satellite imagery from 1992, 2004, 2010 and 2012. In each image locations A-D are in the same locations marking specific bedrock islands (nunataks) within the ice sheet. The yellows arrows indicate the 1992 terminus position in each image, the black arrow denotes the terrain south of bedrock nunatak B. Retreat of the west arm of the glacier has been 3.2 km from 1992 to 2012. The east arm retreat in the last twenty years has been 1.2 km. In 1992 Nunatak A is 1.5 km from the ice edge and is composed of two separate nunataks. By 2010 the two nunataks have merged and by 2012 Nunatak A is 1 kilometer from the ice edge. In 1992 Nunatak B is 3 km from the icefront surrounded by the ice sheet and in 2012 the nunatak has increased in size and extends 1 km beyond the terminus. Nunatak C has largely emerged from the ice sheet, the nunatak has also expanded in length by 500 meters as ice has thinned during the retreat. The Nunatak at D did not exist in 1992, but by 2012 it is over 1 km long.

A close up view of the terminus and Nunatak B and C from 1992 and 2012 illustrates the expansion of the nunataks as ice has thinned. The locations at the green and purple arrows are the same in both images. In 1992 these locations are near the nunatak margin and by 2012 the locations are in the midst of the Nunatak. Qaleraliq Glacier behavior is similar to that of almost all southern Greenland glaciers, most of which like Qaleraliq have not been the focus of detailed study, such as Kuussuup Sermia, Narssap Sermia or Kangiata Sermia. In the Tasermiut Fjord Biggs (2011) noted the retreat of two glaciers Sermitsiaq and Itillersuaq that have each retreated 600 and 300 m respectively from 1987 to 2009.The unusual nature of the 2012 melt season can be seen in this animated graph of ice sheet melt extent with data from Marco Tedesco, Figure 2a in the recent paper submitted (Tedesco et al, 2012).