Regional modelling of ablation in West Greenland

Abstract

Regional assessment of water resources in West Greenland is needed in connection with planning future hydropower projects. Ablation from the Inland Ice and from local glaciers will be an important water source in most basins and a simple model for computing specific ablation has been developed. The model uses air temperatures extrapolated from coastal weather stations and will be eombined with areal data from the West Greenland glacier inventory to give estimates of runoff due to ablation for individual basins. The model is found to somewhat underestimate ablation at lower altitudes whilst greatly overestimating at higher altitudes and work will continue to improve the model. However, the present model applied to the Nordbogletseher in Johan Dahl Land indieates that the standard deviation of the ablation is about a quarter of the long-term mean which suggests that runoff rneasurements would have to be made for many years at the Nordbosø to obtain a reliable mean value for the runoff from the glacier.