제주도 고산지역의 대기 라돈 배경농도 및 시계열 변동

• Published in: 한국대기환경학회지 Vol. 33; no. 2; pp. 174 - 183
• Main Authors: 송정민(Jung-Min Song), 부준오(Jun-Oh Bu), 김원형(Won-Hyung Kim), 강창희(Chang-Hee Kang), 고희정(Hee-Jung Ko), S. Chambers
• Format: Journal Article
• Language: Korean
• Published: 한국대기환경학회 2017
• Subjects: 대기과학; Atmospheric radon; Gosan Site; Cluster back-trajectory; Terrestrial fetch; Background level
• ISSN: 1598-7132; 2383-5346
• DOI: 10.5572/KOSAE.2017.33.2.174

The background level and timely variation characteristics of atmospheric $^{222}Rn$ concentrations have been evaluated by the real time monitoring at Gosan site of Jeju Island, Korea, during 2008~2015. The average concentration of atmospheric radon was $2,480mBq\;m^{-3}$ for the study period. The cyclic seasonality of radon was characterized such as winter maximum and summer minimum, consistent with the reduction in terrestrial fetch going to summer. On monthly variations of radon, the mean concentration in October was the highest as $3,041mBq\;m^{-3}$, almost twice as that in July ($1,481mBq\;m^{-3}$). The diurnal radon concentrations increased throughout the nighttime approaching to the maximum ($2,819mBq\;m^{-3}$) at around 7 a.m., and then gradually decreased throughout the daytime by the minimum ($2,069mBq\;m^{-3}$) at around 3 p.m. The diurnal radon cycle in winter showed comparatively small amplitude due to little variability in atmospheric mixing depth, conversely, large amplitude was observed in summer due to relatively a big change in atmospheric mixing depth. The cluster back-trajectories of air masses showed that the high radon events occurred by the predominant continental fetch over through Asia continent, and the radon concentrations from China continent were about 1.9 times higher on the whole than those from the North Pacific Ocean. The concentrations of $PM_{10}$ also increased in proportion to the high radon concentrations, showing a good linear correlation between $PM_{10}$ and radon concentrations.