Historical fluctuations of calving glaciers in South and West Greenland

Abstract

Fluctuations of calf-ice producing outlets of the Julianehåb ice cap and other local glaciers in South Greenland, and outlets of the Inland Ice in South and West Greenland between latitudes 60° and 73°N from c. A.D. 1850 to the present time are reviewed. Seasonal variations of the fast running tidewater glaciers (ice streams) may veil long term trends, but in general it is concluded that the mode of activity (advance or retreat) is nearly synchronous for the outlets and their neighbouring land-based segments, whereas amplitude differs; topographical control is important for short-term fluctuations but should not be over-emphasised. The situation around 1990 is one of spreading readvance and the observed behavioural patterns fit with Huybrechts' model for the present dynamic situation of the ice cover. This model indicates that the ice sheet generally is expanding as a consequence of the climatic cooling since the Holocene climatic optimum but also locates areas with present thinning of the ice margin.