Anomalous surface elevation, velocity, and area changes of Split Lake Glacier, western Prince of Wales Icefield, Canadian High Arctic

Abstract

Here we use a variety of remote sensing data sets to characterize the evolving extent, surface features, dynamics, and surface elevations of Split Lake Glacier, a small outlet of the Prince of Wales Icefield, Nunavut. The glacier started advancing between 1959 and 1975, with a continued increase in terminus area up to the present day, coincident with significant upper elevation thinning and lower elevation thickening that cannot be accounted for by surface mass balance. The highest velocities reach >600 m year−1, with the region of fastest ice motion focused around an icefall that occurs in a bedrock constriction. Distinctive ogives are present in a 1975 air photo of the glacier for the first time, which suggests that rapid motion started by 1970. These patterns are anomalous when compared with the geometry, velocity, and area changes of all other nearby areas of western Prince of Wales Icefield and suggest that Split Lake Glacier may be a slowly surging glacier. The surge duration of 50+ years is longer than any other previously described surge within the Canadian Arctic Archipelago. These results give further information concerning the wide variety of dynamic and geometrical changes of glaciers across this region.