Parameterization of global and longwave incoming radiation for the Greenland Ice Sheet

Meteorological measurements from various projects on West Greenland are used to parameterize the global and long-wave incoming radiation during summer months for the Greenland Ice Sheet. The parameterizations are based on the independent variables, air temperature, vapour pressure, surface albedo, cloud amount and elevation and can be used to improve results from numerical surface energy-balance models. The parameterization for global radiation contains all of the independent variables. The uncertainty for the various locations is 3% for clear skies and 6 to 7% on average for all cloud conditions. The longwave incoming radiation can be estimated from two equations. One is valid for instantaneous values and one for daily means. The uncertainty is 4% (instantaneous values) and 3% (daily means) for clear skies, and 6% (instantaneous values) and 5% (daily means) on average for all cloud conditions.