Ice velocities of the Lambert Glacier from static GPS observations

Between 1988 and 1995, five seasons of Global Positioning System (GPS) data were collected at seventy-three locations near the 2500 metre contour of t he Lambert Glacier Drainage Basin (LGB). These data have been processed usi ng GAMIT/GlobK software to determine surface velocities at the surveyed sit es. Results show that velocities along the traverse route vary between 0.5 ma(-1) and 63 ma(-1) with the location of the major outlet glaciers inside the LGB clearly identifiable within the data. A subset of the LGB GPS data has been studied to investigate an efficient method for determination of ic e velocities at remote sites within a single field season. Results from thi s study have shown that ice velocities within 2% of the long-term estimate may be determined using two to four hour GPS site occupations separated in time by a minimum of forty days.