후쿠시마 서쪽 해역(동해)에 도달한 후쿠시마 다이이치 원전 기원 방사성 세슘

Abstract

Korean Peninsula is located about 1000 km westward from Honshu Island of Japan. Radionuclides started to be released on March 12 into the atmosphere from the damaged reactors in Fukushima, eastern coast of Honshu Island. Radiocesium appeared to arrive over the Korean Peninsula first on March 24 and the atmospheric activity concentrations of 134Cs and 137Cs peaked around April 7 and subsequently decreased toward the end of April with occasionally detected in the early May. The Fukushima originated radiocesium appeared to be largely arrived in Korea from the west rather than the east due to the prevailing westerlies at that time. The seas adjacent to Korean Peninsula, Yellow Sea, Korea Strait, and the East Sea (Sea of Japan) were monitored from March 30 to June 8. 134Cs and 137Cs in the surface waters were found to be 0.11 ~ 1.19 and 1.3 ~ 3 mBq/kg, respectively. The 134Cs were detected on March 30 and increased to April 8 in the Korea Strait, probably reflecting the temporal atmospheric 134Cs concentration peak. The activity ratios between 134Cs/137Cs were 0.1~ 0.5. Samples are still being measured and we will report our findings in relation to the earlier measurements in the seas to Korean Peninsula at the meeting.eared to arrive over the Korean Peninsula first on March 24 and the atmospheric activity concentrations of 134Cs and 137Cs peaked around April 7 and subsequently decreased toward the end of April with occasionally detected in the early May. The Fukushima originated radiocesium appeared to be largely arrived in Korea from the west rather than the east due to the prevailing westerlies at that time. The seas adjacent to Korean Peninsula, Yellow Sea, Korea Strait, and the East Sea (Sea of Japan) were monitored from March 30 to June 8. 134Cs and 137Cs in the surface waters were found to be 0.11 ~ 1.19 and 1.3 ~ 3 mBq/kg, respectively. The 134Cs were detected on March 30 and increased to April 8 in the Korea Strait, probab