An atmospheric transport mechanism of Australia-originated radon to Syowa station, Antarctica

Atmospheric radon (Rn) and thoron (Tn) measurement was carried out at Syowa station, Antarctica in the 2005 wintering season by JARE-46. The half life of Rn is 3.8 days and that of Tn is 55 seconds. This paper attempts to extract some cases in which the atmosphere contains a distant place originated Rn, based upon the vertical distribution of Rn and Tn. The origins of Rn in the extracted cases were specified by comparison with a global atmospheric radon transport model. While South America was the most common and frequent contributor among continents over all, the Australian continent was the major contributor in one case. The latter half of this paper examines the transport route and the effective atmospheric circulation of the Australian Rn to Syowa Station