Anthropogenic impact on snow chemistry of king George island, antarctica-ice core shows distinct nssNO_4~(2-) and NO_3~- raising after 1960s

摘要

A time scale for the ice core extracted from Collins Ice Cap, King George Island, Antarctica is well established upon detailed glaciological investigations, and checked with historic volcanic events shown up. Age-depth profiles displaying doubling of nssSO_4~(2-) and NO_3~- concentration for two stages are, thus, determined. Ignoring long-term volcanic effect, and sorting out the fraction devoted by moraine biogenic origin, anthropogenic input of nssSO_4~(2-) into the regional atmospheric chemistry could then be evaluated. Both the increases of nssSO_4~(2-) on the biogenic level and NO_3~- on the natural background are attributed to the founding of manned stations in the island during the period of 1968-1987, and to the intensive human activities over 20a from late 1960s on.. Several works are advocated for future aerosol sampling, to make up for the shortcomings in the resolution of present record and to understand the mechanisms for the transport and deposit of anthropogenic pollutants.