Abstract
Continuous measurements of radon-222 were conducted at Comandante Ferraz (62°S, 58°W), a Brazilian station in the Antarctic Peninsula, during the winters of 1986 and 1987. The average concentration of radon-222 was 0.026 ± 0.018 Bq m-3 in 1986 and 0.014 ± 0.008 Bq m-3 in 1987. The higher average of 1986 was attributed to the stronger winds in 1986 compared to those observed in 1987. Large surges of radon reaching up to 0.13 Bq m-3 were affected by local radon emissions due to soil defrosting. Bare soils and atmospheric stability also favored local contributions. Radon peaks attributed uniquely to air mass trajectories passing over the South American continent occurred during the 2 years of monitoring. Periodicities of 25 to 30 days in the time series of radon corroborate with previous results obtained by other authors in east Antarctica.