April 28, 2016

Krayniy Glacier Retreat, Novaya Zemlya

Posted by Mauri Pelto


Krayniy Glacier (Ky) comparison in 1990 and 2015 Landsat images.  Red arrow is 1990 terminus and yellow arrow is the 2015 terminus.  Purple arrows indicate upglacier thinning and green arrow a location of a glacier dammed lake.

Krayniy Glacier is an outlet glacier that drains the northern side of the Novaya Zemlya Ice Cap into the Barents Sea. This outlet glacier is just southwest of Tasija Glacier (T) and like that glacier has retreated over 1.2 km since 1988. Krayniy Glacier has been retreating like all tidewater glaciers in northern Novaya Zemlya (LEGOS, 2006). The terminus of the glacier has a pinning point on an island at present. Carr et al (2014) identified an average retreat rate of 52 meters/year for tidewater glaciers on Novaya Zemlya from 1992 to 2010 and 5 meters/year for land terminating glaciers. The increased retreat rate coincides with the depletion of ice cover in the Barents Sea region and a warming of the ocean. Both would lead to increased calving due to more frontal ablation and notch development similar to at Svalbard (Petlicki et al. 2015).  The spring of 2016 features an ice free west coast of Novaya Zemlya leading to enhanced calving front melting.

In 1990 the glacier had an east west terminus across the head of the fjord.  There was a substantial glacier dammed lake impounded by the glacier (green arrow), and there was a narrow connection with Tasija Glacier.  The glacier dammed lake persisted in Landsat images in 1999, 2000, 2003 and 2006.  In 2013 the proglacial lake had drained.  In 2014 and 2015 the lake has not reformed, an indication of glacier thinning at the outlet location. This thinning is evident at both purple arrows,where the connection with the Tasija Glacier has been severed and a substantial nunatak has emerged amidst the glacier. From 1990 to 2015 the glacier has retreated more on the eastern margin with 1250 of retreat opening up the embayment.  Retreat at the island in the glacier center has been 500 m since 1990. The western section of the glacier has retreated little. The eastern embayment will continue to drive retreat and glacier thinning that will reduce contact with the island pinning the eastern half of the glacier.  The thinning is evident at the purple arrows. The glacier will likely retreat from this island in a fashion similar to Tasija and Chernysheva, which will lead to increased rate of retreat of the entire ice front.

kraniy lake

1988, 2006 and 2014 Landsat images indicating the continued presence of glacier dammed lake from 1988-2006 and continued absence from 2014 and 2015.arctic.seaice4262016

Sea ice image from Cryosphere Today