Airborne Resurveys of the Southern Greenland Ice Sheet

Airborne laser-altimeter flight lines from 1993 over southern parts of the ice sheet were resurveyed with almost complete repeat coverage. In 1993 and 1994, NASA surveyed the entire Greenland ice sheet by airborne laser altimeter, obtaining surface-elevation profiles with root mean square (rms) accuracies of 10 cm or better (Krabill 1995) along flight lines that crossed all the major catchment basins. In 1998, the ten flight lines flown in 1993 in the south of Greenland were resurveyed with about 99% repeat coverage; flight lines in the north will be resurveyed in 1999. Additional flights in 1998 were over glaciers, identified by E. Rignot, where existing SAR data give information on ice motion.