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ISSN 0253-2964(Print) ISSN 1229-5949(Online)
Volume 35, Number 4
BKCSDE 35(4)
April 20, 2014 |
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Title |
Background Level of Atmospheric Radon-222 Concentrations at Gosan Station, Jeju Island, Korea in 2011 |
Author |
Won-Hyung Kim, Hee-Jung Ko, Chul-Goo Hu, Haeyoung Lee, Chulkyu Lee, S. Chambers, A. G. Williams, Chang-Hee Kang* |
Keywords |
Radon-222, Atmospheric radon, Background level, Gosan Station, Back trajectory |
Abstract |
Real-time monitoring of hourly atmospheric radon (Rn-222) concentration was performed throughout 2011 at Gosan station, Jeju Island, one of the least polluted regions in Korea, in order to characterize the background levels, and temporal variations on diurnal to seasonal time-scales. The annual mean radon concentration for 2011 was 2527 ± 1356 mBq m−3, and the seasonal cycle was characterized by a broad winter maximum, and narrow summer minimum. Mean monthly radon concentrations, in descending order of magnitude, were Oct > Sep > Feb > Nov > Jan > Dec > Mar > Aug > Apr > Jun > May > Jul. The maximum monthly mean value (3595 mBq m−3, October), exceeded the minimum value (1243 mBq m−3, July), by almost a factor of three. Diurnal composite hourly concentrations increased throughout the night to reach their maximum (2956 mBq m−3) at around 7 a.m., after which they decreased to their minimum value (2259 mBq m−3) at around 3 p.m. Back trajectory analyses indicated that the highest radon events typically exhibited long-term continental fetch over Asia before arriving at Jeju. In contrast, low radon events were generally correlated with air mass fetch over the North Pacific Ocean. Radon concentrations typical of predominantly continental, and predominantly oceanic fetch, differed by a factor of 3.8. |
Page |
1149 - 1153 |
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