| Summary: | A detailed snow pit study at Dye 3, South Greenland, has been carried out in order to investigate the seasonal variations of 10 Be, Cl - , NO 3 - , SO 4 2- , H 2 O 2 , 210 Pb, 3 H, Mn and δ 18 O. Special emphasis was placed on understanding the causes of 10 Be variations because this isotope can be used to trace the history of solar activity. A sampling interval of 5 cm was chosen to assure a mean time resolution of about 20 samples per year for the period 1978-1983. Four different categories of seasonal variations were identified: strong summer peaks (δ 18 O, H 2 O 2 , 3 H), weak bimodal peaks (NO 3 - , SO 4 2- , conductivity, 10 Be), a fall peak ( 210 Pb) and a winter-spring peak (Cl - , Mn). Although we are still far from a detailed understanding of the mechanisms which control the measured compositions, there are indications that different processes dominate at different seasons. NO 3 - , SO 4 2- , Mn and Cl - variations suggest that aerosol transport is most important during winter-spring. In summer-fall there seems to exist a second period of long range transport from low latitude continental areas resulting in enhanced concentrations of 210 Pb, 10 Be and SO 4 2- .
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