福岛核事故泄漏进入海洋的137Cs对中国近海影响的模拟与预测  

Simulation and prediction of ^(137)Cs from the Fukushima accident in the China Seas

作　　者：赵昌[1] 乔方利[1] 王关锁[1] 夏长水[1] JUNG Kyung Tae 

机构地区：[1]国家海洋局第一海洋研究所,青岛266061 [2]Korea Institute of Ocean Science and Technology, Ansan-Si 426-744, Korea

出　　处：《科学通报》2014年第34期3416-3423,共8页Chinese Science Bulletin

基　　金：中韩海洋核安全监测及预测系统研究资助

摘　　要：2011年3月日本福岛第一核电站遭受海啸侵袭,引起大量放射性物质泄漏进入海洋和大气,进入大气通道的放射性物质大部分沉降于海洋上,其中进入大气中的137Cs(总量约13 PBq)有38.5%沉降于日本东部海域,对海洋造成二次污染.本文在POM环流模式中引入放射性物质在海洋中的输运、沉降和衰变的控制方程,建立了一个准全球放射性物质数值模式,模拟并预测了福岛核事故泄漏的放射性物质137Cs的长期输运情况,分析了该泄漏物质通过海洋途径进入中国近海的过程.结果表明:福岛核事故泄漏的137Cs于2013年开始对中国近海海域造成影响,其浓度和影响范围在未来5~6年将逐渐增加,2018年前后黄东海和南海北部的137Cs浓度达到最高值.南海中南部浓度小于黄东海和南海北部,且最大浓度出现时间滞后于其他海域,所有中国近海海区137Cs浓度达到最大值后在自身衰减的作用下逐渐降低;137Cs在中国近海的浓度小于外海,在黑潮外部海域由于黑潮的强流屏障作用会形成一个137Cs浓度高值区;137Cs在中国近海浅水海域上下混合均匀,在深水区上层水体的137Cs(上400 m)浓度要明显大于下层,在南海200~400 m层水体形成一个高值区.In the Japan’s Fukushima Daiichi nuclear power plant accident accompanied the great Tohoku earthquake and tsunami on 11 March 2011, enormous amounts of radionuclides were emitted into the atmosphere and the ocean. The radionuclides into the atmosphere were transferred to the land and the ocean through wet and dry deposition. As for 137 Cs, the amount deposited into the Pacific Ocean east of Japan was estimated to be 5 PBq. Based on the Princeton Ocean Model（POM） and diffusion equation of radioactive materials, a quasi-global ocean radionuclides model was established to study the long-term transport, distribution and evolution of 137 Cs in the ocean from the Fukushima accident. The simulation on the distribution of 137 Cs agrees well with the observed profiles on 9 November 2011, which proved the validity of the model. The process of 137 Cs spreading into China Seas via ocean path was analyzed based on the model result. It shows that in 2013, 137 Cs starts getting into the China Seas. The coverage and concentration of 137 Cs increase gradually in the following 5–6 years. The 137 Cs concentration in the Yellow and East China Seas, South China Sea reach the peak value around 2018 and gradually decreases after it due to its own decay. And the concentration in the southern South China Sea is lower than that in the other China Seas. Owing to the barrier of the Kuroshio, the 137 Cs concentration in the China Seas is lower than that in open seas. Meanwhile, a high concentration area formed to the eastern wing of the Kuroshio. At shallow regions in the China Seas, the vertical profile of the 137 Cs concentration is almost uniform. At deep regions in the China Seas, the 137 Cs concentration is higher in the upper layers（〈400 m） than in deep layers. In the South China Sea, a peak value was found at a depth between 200 and 400 m.

关 键 词：福岛核事故 137Cs 放射性物质模式 中国近海 

分 类 号：X55[环境科学与工程—环境工程] X591