Exit Glacier Mass Balance

Tetreau, Michael

On May 1, 1999 RMS Mike Tetreau and park VIP Mike O Brien skied to the top of Exit Glacier to determine winter snow accumulation. They dug a pit near the middle of the glacier at the following location (as determined with a PLGR GPS unit): 60º 10 18.37 , 149º 41 30.57 ±18 ft., elev. 2692 feet asl, using the NAS-D datum. Conditions were bright and sunny, although there was a constant 20-25 knot wind that made for uncomfortable conditions on the surface. It took approximately 5 hours to dig the pit and make the measurements noted below. Overall, the snow was incredibly dense and digging was very difficult (a steel shovel with a pointed tip would be good to have on the next trip). The snow tubes that are used for the monthly snow surveys for the NRCS were used to determine water content and density. Only four tubes (approximately 120 inches) were available, but that did not matter since it was impossible to core more than 107 inches down from the surface due to extremely dense snow. Coring down in the pit was extremely difficult and we would often only be able to core six inches or so at a time.