An ice-core chemistry record from Snøfjellafonna, northwestern Spitsbergen

A 2.2 m deep pit and the top 42.5 m of an ice core recovered at Snøfjellafonna, northwestern Spitsbergen, were continuously analyzed for Na+, Cl−, NO3 −, SO4 2− and pH. Seasonal variations in ionic concentrations seem to have remained in the pit and the core, in spite of the relatively severe summer melting. We dated the core by counting annual peaks of Na+ and made an adjustment with the use of a tritium peak in 1963 as a reference horizon. It turned out that the depth of 42.5 m went back to the early 1930s or late 1920s. The 60–70 year record of snow chemistry showed that the concentrations of both NO3 − and SO4 2− had increased in the 1950s and had decreased in the late 1970s and the 1980s. The increase would be explained in terms of anthropogenic inputs from the industrial areas. The later decrease of the same ions may have been caused by a combination of the reduction of the atmospheric precursors due to pollution controls and the meltwater-associated processes.