Cambridge University Press, Annals of Glaciology, (27), p. 385-390
DOI: 10.3189/1998aog27-1-385-390
Cambridge University Press, Annals of Glaciology, (27), p. 385-390
DOI: 10.1017/s0260305500017778
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Seasonal cycles of the chemical species Na+, K+, Mg2+, Ca2+, CH3SO3- (MSA), Cl-, NO3- and SO42- in the Dome Summit South (DSS) ice core from Law Dome were measured for a number of epochs (AD 1809-15, 1821-31, 1980-92) spanning a total of 28 years. These preliminary trace-chemical patterns show that the DSS site is mainly affected by marine air. The main features found in the seasonal pattern of sea-salt concentrations (e.g. Na+, Cl- and Mg2+) were a winter peak and a summer minimum. The variations in sea salts are believed to reflect aerosol production and transport due to the level of storminess, and are less affected by sea-ice extent. The seasonal cycles of marine biogenic compounds, non-sea-salt SO42- and MSA are in good agreement. They show a characteristic summer maximum and a winter minimum, due to variations in biological activity. While the main sources of nitrate in polar snow remain unclear, the seasonal signal, including sub-seasonal structure, at DSS resembles that found in the atmosphere at coastal Antarctic sites. However, the timing of the nitrate maximum is different in the ice-core record compared with the aerosol records. Overall, the results indicate that the DSS core, with sub-seasonal resolution, contains a sensitive record for investigating climate variability.