Deposition patterns of atmospheric 7Be and 210Pb in coast of East China Sea, Shanghai, China

Abstract

In complied data of atmospheric deposition of 210Pb and 7Be in the world, the data from China is of lack. In the present paper, atmospheric depositional fluxes of 7Be and 210Pb were simultaneously measured in semimonthly interval for 1 year (from November 2005 to October 2006) at Shanghai (31°13′39″N, 121°23′56″E), China, 50 km from the coastal of East China Sea. The annual average flux of 210Pb and 7Be in 2006 is 4.79×10 2 and 2.07×10 3 Bq m −2 year −1, respectively. Compared with the published data, the highest flux of 210Pb in 2006 at Shanghai was clearly observed during studying periods. The possible reason for such high flux of 210Pb is discussed. Furthermore, deposition fluxes of both 210Pb and 7Be show varieties in seasons: highest flux of 210Pb in winter (November–August) and that of 7Be in spring (March–May). Moreover, the correlation between activity fluxes and precipitation are weak both for 7Be and 210Pb in whole of 2006; however, the high correlation are observed in autumn and spring for 7Be and that only in autumn for 210Pb.