June 14, 2018

Coutts Ice Cap, Baffin Island Fragmentation

Posted by Mauri Pelto

Coutts Ice Cap in  Landsat images from 1986 and 2017.  The terminus location of the main glacier terminating in the large lake is indicated by dots.  Tributary Glaciers 1-6 represent locations where glaciers have separated or a glacier has retreated from a lake. 

Coutts Ice Cap is on between Coutts Inlet to the west and Buchan Gulf to the east on the north shore of Baffin Island near its northeastern tip (see map below).  Here we are focused on a group of glacier that descend into a basin, that I refer to as Coutts Basin and Coutts Basin Lake. Gardner et al (2012) and Sharp et al (2011) both note that the first decade of the 21st century had the warmest temperatures of the last 50 years in the region, the period of record, and they identified that the mass loss had doubled in the last decade versus the previous four for Baffin Island. This led to surface lowering of up to 1 m/year on all ice masses on Baffin Island and Bylot Island between 1963 and 2006 (Gardner et al. 2012).

In 1986 the Tributary Glacier 1 (TG1), flows into the Coutts Lake basin joining with TG2.  TG3 feeds into the Coutts Basin glacier system.  TG4 has a significant piedomont lobe but terminates short of the Coutts Basin Lake. TG5 reaches the northern shore of Coutts Basin lake. TG6 drains into a secondary lake above the main Coutts Basin.  The main terminus of the Coutts Basin Glacier, red dots extends east to west across the lake. In 1999 the snowline is higher and there are minor changes, but retreat is limited and none of the glaciers have separated.  In 2016 the snowline is very high at 1500 m, leaving only a small part of the ice cap with snowcover. The high snowline in August 2016 have observed on Borden Ice Cap and Penny Ice Cap and have driven thinning and retreat there as well. TG1 no longer merges with TG2.  There is a separation of the glacier lobes at TG2.  TG3 no longer substantially feeds the Coutts Basin.  TG4 has thinned and retreated from near the short of Coutts Basin Lake. TG5 has receded from the lake shore.  TG6 has retreated from the upper lake. In 2017 the margin of the main Coutts Basin Glacier no longer extends across the lake, yellow dots. The snowline in August 2017 is at 1100 m lower than 2016.

Way (2015) noted that summer temperatures have warmed more than 1 C after 1990 on the Cumberland Peninsula at the south end of Baffin leading to a 18-22% decline of  Grinnell and Terra Nivea Ice Cap.

Coutts Ice Cap in  Landsat images from 1999 and 2016.  The terminus location of the main glacier terminating in the large lake is indicated by dots.  Locations 1-6 represent locations where glaciers have separated or a glacier has retreated from a lake. 

Map of the region indicating Cape Jameson (CJ), Coutts Inlet (CI), Buchan Gulf (BG), North Arm (NA), Coutts Basin Lake (CBL) and Coutts Ice Cap (CIC).