<h2>AAS  96-206</h2><h2>ESTIMATION OF ICE SHEET SURFACE ELEVATION CHANGE FROM THE EOS ALTIMETER SATELLITE (ICESAT) CROSSOVER SIMULATION</h2><h4>C. J. Choe and B. E. Schutz, The University of Texas at Austin</h4><h2> Abstract </h2>A simulation study has been undertaken to assess the GLAS concept of detecting ice surface change over the Antarctica by crossover analysis.  The objective is to determine whether GLAS would be able to detect changes of the major ice sheets at crossovers in the presence of several error sources.  The area of interest was chosen at 74S < lat  < 82S; 135E < lon < 180E and crossovers were obtained from a 183-day repeat ICESAT repeat ground track.  The result shows that pointing error becomes the largest error on the order of 6cm for each degree of surface slope.<br><br>