Accumulation map for the Greenland Ice Sheet: 1971-1990

An updated accumulation map for the Greenland Ice Sheet for the period 1971 -1990, based on kriging of accurate point estimates developed during the pa st decade at over 40 points plus over 200 historical points, shows an avera ge water accumulation of 30 g cm(-2)yr(-1). Average uncertainty (standard d eviation) in estimates of point accumulation for the interior part of the i ce sheet, where the kriging drift surface is well constrained, is approxima tely 7 g cm(-2)yr(-1), or 24% of mean accumulation. Because there are multi ple cores in most regions, the regional uncertainty in accumulation should be considerably lower than the 7 g cm(-2)yr(-1) average uncertainty at a po int. There are still many areas on the ice sheet, including northwest and s outhern Greenland, where annual accumulation remains poorly constrained.