The Relationship Between the Drainage Areas and Sizes of Outlet Troughs of the Sukkertoppen Ice Cap, West Greenland

ABSTRACT

The dimensions of a sample of ‘Icelandic’ troughs forming the northern outlets of the Sukkertoppen ice cap in West Greenland are correlated with their catchment areas and their distance from the sea (representing dropping net annual accumulation inland). A correlation coefficient of 0.93 is found, with drainage area dominating the relationship (0.71). The remaining variance seems to be due to a number of factors each of minor importance, which may include confluence of ice, slight geological variations and variations of ice cap thickness. The encouragingly high correlations obtained despite the small sample (19) lead one to suppose that, as the local topography suggests, these Sukkertoppen troughs can be explained solely by reference to their own present day drainage basins and are distinct from the much larger, differently oriented major troughs, like Søndre Strømfjord, which were used by the inland ice sheet in the Pleistocene. The results also suggest that, like river channels in fluvial environments, glaciated valleys eventually may become adjusted to the glacial ‘system’ in which they are formed. Such findings could also have a wider use in the interpretation of areas of Pleistocene glaciation.