Glacier hydrology in Svalbard, Norwegian High Arctic

Progress in glacier hydrology has focused on temperate glaciers, although partly or wholly non-temperate glaciers are found in many parts of the world, and significant areas of former ice sheets were probably non-temperate. It has usually been assumed that drainage from nontemperate glaciers consists of relatively dilute and invariable supraglacial runoff. In this paper, the hydrology of glaciers in the High-Arctic archipelago of Svalbard is examined. Variations in the thermal regimes of glaciers, and their implications for drainage, are first addressed. Results from Svalbard concerning meltwater discharge and storage, and solute and suspended-sediment dynamics are then reviewed. In general, meltwater penetration of non-temperate ice is limited, and drainage from non-temperate glaciers in Svalbard has many of the characteristics of sub-aerial drainage. However, it would be erroneous to view this drainage simply as dilute supraglacial runoff, as significant material transport occurs in suspension and solution. Furthermore, twentieth-century climate change has probably led to changes in the thermal regimes of some Svalbard glaciers, such that relict drainage structures are sometimes observed, while meltwater yields are augmented by runoff which can be attributed to the loss of mass from glaciers. At large spatial scales, turbid plumes observed at the marine margins of polythermal ice caps indicate that meltwater can be routed subglacially through non-temperate ice. Copyright (C) 1998 Elsevier Science Ltd.