Abstract:

Snowpits samples were collected from three glaciers in the Longyearbyen region, Svalbard during March to May, 1996. Among major chemical species (Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl^-, NO₃^- and SO₄^2-), Cl^- and Na⁺, which come mainly from sea salt aerosol, are the dominant soluble impurities in snowpits. In dirty layers of snowpits (representing autumn), the crustal cation Ca²⁺ has the highest concentration among all species. Thus, snowpits have been dated by high values of Ca²⁺ concentrations and less negative δ¹⁸O, which represent autumn and summer layers respectively. Seasonal variations in concentrations of sea salt ions ( Na⁺, Mg²⁺ and Cl^-), SO₄^2- and NO₃^- have been identified. Results indicate that concentrations of these ions show high value in spring and summer. The spring maximum value likely results from long range transport of marine aerosol from north Atlantic storms( Na⁺, Mg²⁺ and Cl^-) and mid latitude anthropogenic pollution (SO₄^2- and NO₃^-). In summer, high concentrations of the sea salt species are attributed to local marine aerosol. The summer SO₄^2-  maximum likely reflects a combination of local marine aerosol, high scavenging ratios, and oxidation of marine biogenic emissions. In comparison, NO₃^- maximum may reflect lightening in the atmosphere and high scavenging ratios. In general, the major ion concentrations in snowpits in Svalbard is high in comparison with those found in snowpits from other remote regions, such as Greenland, Antarctic and Qinghai Tibetan Plateau, especially for sea salt species.

Key words: Longyearbyen in Arctic, snowpits, ion concentrations, seasonal variations