Movement observations on the Greenland Ice Cap
Special ReportSummary: Certain positions on the Greenland Icecap, established by the French in 1951, were redetermined in 1955 by observations of the sun to measure movement of the ice surface. The movement of 774 m in 4 years in a southern direction (not with the surface slope) was noted for the Central Station, confirming French findings. The direction of the movement may be due to the deflection of ice to the south by a 20-mi. ridge (discovered by seismic measurements) rising 760 m. in 10 west of the station. A motion of 611 m in a western direction was measured at Mile 100, indicating the importance of surface slope for ice movement at this point halfway between Central Station and the firn line. Assuming a constant velocity with depth, the total flow of ice per year in a 1-m cross section is calculated at 360,000 m^3 while accumulation over the 100 miles between Mile 100 and Central Station is 82 m/yr. The uncertainty of the measures is large since the time scale is so short.
U.S. Army Snow, Ice, and Permafrost Research Establishment.Engineer Research and Development Center (U.S.)
Glaciers; Glacier ice; Glacier movement; Glacier flow; Greenland; Project Jello
Special report (U.S. Army Snow
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