| Summary: | In August of 1991 and June of 1992, conventional leveling was done to measure surface topography along a 40 km line located on the western flank of the Greenland Ice Sheet. Data were collected by R.H. Thomas, K. Kuivinen, and K. Jezek in 1991 and by R.H. Thomas, K. Kuivinen, P. Gogineni, D. Anderson, and K. Jezek in 1992. Leveling measurements were carried out in conjunction with surface Global Positioning System (GPS) measurements to serve as an independent control site for future airborne and spaceborne altimetry experiments. Level line elevations were adjusted to an absolute datum using one of our surface GPS observations. This reduced absolute coordinate of leveling data can be used to compare other surface elevation measurement methods such as the Airborne Oceanographic Lidar (AOL) instrument. Analysis of the leveling data yield a highly accurate estimate of relative ice sheet elevation above the geoid. Elevation above the ellipsoid can be estimated tying the level data to a derived GPS datum and adjust the remaining level data with a geoid model. In addition to surface elevation, data on ice sheet surface relief and accumulation rate are reported.
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