Glacier distribution and direction in Svalbard, Axel Heiberg Island and throughout the Arctic: General northward tendencies

Abstract

Glacier distribution and direction in Svalbard, Axel Heiberg Island and throughout the Arctic: General northward tendencies

Arctic glaciers depend on supply of moisture, mostly from the Atlantic. The snowline is remarkably high in northeast Siberia, remote from this source. Because of differential solar radiation receipt, local glaciers have a northward-facing tendency throughout the Arctic. This is weaker than in dry mid-latitudes but low sun angles enhance the effects of shading, compensating for the broader range of aspects ([i.e.] slope directions) illuminated in summer. Statistics from the World Glacier Inventory and other sources show that mass balance differences between slopes of different aspects give both more glaciers, and lower glaciers, facing the favoured direction: usually North. This is clear, for example, for local glaciers (and for all small glaciers) in central Spitsbergen and in Axel Heiberg Island. Wind effects (drifting snow to leeward slopes) are much less important, except in northwest Europe from Norway to Novaya Zemlya which is under the strong influence of westerly winds, greatest in the Polar and Sub-polar Urals. A thorough analysis is provided of aspect data for local glaciers within and near the Arctic Circle, and of variation in glacier mid-altitude with aspect and position. There is consistency between mean glacier aspect (in terms of numbers) and aspect with lowest glaciers, everywhere except in Wrangel Island.