The Balance of the Greenland Ice Sheet

Abstract

AbstractPlanimetry of the 15 maps of scale 1:1,000,000 of the World Aeronautical Chart, U.S.A.F., gives 1.726 × 106 km.2 for the surface area of the Greenland Ice Sheet. The hypsometric curve obtained by measuring the area between contours at 1000-ft. (305 m.) intervals with a planimeter gives 2135 m. for the mean height of the ice sheet. The normal area distribution curve of the ice sheet shows that is certainly in the “Inland Ice” type in Ahlmann’s classification. The mean firn line of the ice sheet is at a height of 1390 m. The discharge from the glaciers in the form of icebergs is estimated to be 215 km.3 of water per year, and the nett balance of the ice cap is negative and about 100 km.3 of water per year.