Ice-Core Analysis at Site A, Greenland: Preliminary Results

Ice-core drilling at Site A, Greenland (70°45′N, 35° 57.5′W; 3145m a.s.l.) by the Polar Ice Coring Office recovered two cores of about 100 m each, which are now in storage awaiting further analysis. Field studies show that visible strata in the cores record both individual storms and individual years; a typical year comprises 15 storm deposits. Pore close-off occurs between 75 and 80 m depth. The grain-growth rate in isothermal firn and ice is about 7.8 × 10 −3 mm 2 a −1 , the 10 m temperature is about –29.5°C, and the accumulation rate over the last 200 years is about 290 mm a −1 ice. Melt events occur about once every 40 years, and major events can be correlated between cores separated by 20 m.