Radon flux at King George Island, Antarctic Peninsula

Fluxes of Rn-222 from the ice-free terrain to the atmosphere were measured directly, for the first time, at the Brazilian Antarctic Station Ferraz during the summer field campaign of 1998/99. Average value for the flux was 7.7 +/- 4.8x10(-2) atoms cm(-2) s(-1) and it ranged between 0.21x10(-2) atoms cm(-2) s(-1) and 28x10(-2) atoms cm(-2) s(-1). The average flux of Rn-220 was estimated to be 23 atoms cm(-2) s(-1), using a combination of two techniques: nuclear track detection and alpha spectrometry of radon daughters. It was found that the production of radon by uranium (41.54 +/- 7.17 Bq kg(-1)) and thorium (57.97 +/- 12.14 Bq kg(-1)) equivalent soil contents, and a diffusion coefficient derived from experimental data for the local terrain could account for this average flux. Nevertheless, the large surges of Rn-222 in the atmosphere frequently observed for that area could not be-explained by this flux only. (C) 2002 Elsevier Science Ltd. All rights reserved.