Description:
Oerlemans et al. (1998) conducted modelling experiments for a sample of 12 glaciers and ice caps, to determine volume changes under a range of temperature and precipitation forcings (Fig. 3). The range of glacier response is very wide, so a key issue is fnding ways to upscale the results of modelling this tiny sample of glaciers to large regions. Figure 2 shows the results of two alternative weighting procedures. Although the absolute values of volume change differ, the results imply that with a warming rate of 0.04° C yr–1 (4° C per century) and no increase in precipitation, little glacier ice would be left by 2100, whereas if warming is restricted to 0.01° C yr–1 and precipitation increases by 10% per degree of warming, then ice losses will be restricted to 10 to 20% of the 1990 value. It must be emphasized that the results are far from certain, and that the actual response of glaciers will exhibit considerable regional variability.