Glacier velocities and dynamic ice discharge from the Queen Elizabeth Islands, Nunavut, Canada

Abstract

Recent studies indicate an increase in glacier mass loss from the Canadian Arctic Archipelago as a result of warmer summer air temperatures. However, no complete assessment of dynamic ice discharge from this region exists. We present the first complete surface velocity mapping of all ice masses in the Queen Elizabeth Islands and show that these ice masses discharged~2.6 ± 0.8 Gt a À1 of ice to the oceans in winter2012. Approximately 50% of the dynamic discharge was channeled through non surge-type Trinity and Wykeham Glaciers alone. Dynamic discharge of the surge-type Mittie Glacier varied from 0.90 ± 0.09 Gt a À1during its 2003 surge to 0.02 ± 0.02 Gt a À1 during quiescence in 2012, highlighting the importance of surge-type glaciers for interannual variability in regional mass loss. Queen Elizabeth Islands glaciers currently account for~7.5% of reported dynamic discharge from Arctic ice masses outside Greenland.

Glacier Surface Velocity Retrieval Using D-InSAR and Offset Tracking Techniques Applied to Ascending and Descending Passes of Sentinel-1 Data for Southern Ellesmere Ice Caps, Canadian Arctic

“…Between 2005 and 2009, CAA ice caps suffered the most negative trends in their observational records [38]. These trends show that the SMB in the NCAA is moving from a mass loss predominantly dominated by calving during the 20th century to a contemporary mass loss driven by meltwater runoff [34,[38][39][40].…”

“…Finally, many research papers indicate a clear increase in ice mass losses and associated contribution of Canadian Arctic glaciers to sea-level rise during recent years. This increase in mass loss is mostly caused by surface melt and runoff, and not by glacier dynamics [38][39][40][41]45].…”

“…Other studies point to a high interannual variability of the velocities of the large outlet glaciers [44]. van Wychen et al [39] showed that velocity changes associated with the termination or initiation of surges can rapidly change the rate of ice discharge to the oceans. Finally, many research papers indicate a clear increase in ice mass losses and associated contribution of Canadian Arctic glaciers to sea-level rise during recent years.…”

“…Many of them are tidewater glaciers located in the high-precipitation coastal areas [39,41,42]. Independent of this surge behaviour, glacier ice velocities during the summer are typically an order of magnitude larger than the mean annual velocities, and summer calving rates are 2-8 times larger than the annual average [41,43].…”

An Inter-Comparison of Techniques for Determining Velocities of Maritime Arctic Glaciers, Svalbard, Using Radarsat-2 Wide Fine Mode Data

“…This is especially true for marine terminating glaciers, where measurements of ice motion can be combined with ice thickness information to determine frontal ablation rates, and hence the contribution of glaciers and ice sheets to global sea level rise. In light of this, in recent years there has been a concerted effort to map glacier dynamics at the regional scale for many of the glaciated regions of the world: Antarctica [1], the Greenland Ice Sheet [2,3], the majority of Alaskan glaciers [4,5], the Canadian High Arctic [6][7][8] and South America [9][10][11].…”