福岛第一核电站事故及核污水排海进入中国海路径及其影响

Transport pathway of radioactive materials and nuclear sewage discharged from the Fukushima Daiichi Nuclear Power Plant accident into the China Sea and its impact

自2011年3月日本福岛第一核电站事故发生以来,其对中国海的影响一直备受国内高度关注。基于近10年的研究成果,本文综述了福岛第一核电站事故释放的放射性核素进入中国海的海洋传输路径主要为表层环流和模态水(亚热带模态水和中央模态水),经表层环流和模态水到达中国海的时间尺度分别在10—15年和2—3年之间。对比分析福岛第一核电站事故前后可知:南海^(137)Cs活度持平,黄海^(137)Cs活度稍有降低,但东海^(137)Cs活度有所升高。鉴于目前有限的监测站位和短期的观测时间,福岛第一核电站事故对中国海的影响程度大小还有待于长期监测和进一步的评估。同时针对日本政府宣布福岛第一核电站核污水排海计划,分析了其潜在的风险和指出了未来的研究方向。

Since the occurrence of the Fukushima Daiichi Nuclear Power Plant(FDNPP)accident in March 2011,its environmental impact on the China Sea has become of considerable public concern.Based on previous studies in the past ten years,we determined that the transport pathways of radionuclides released by the FDNPP accident into the China Sea are mainly surface circulation and mode water(i.e.,subtropical and central mode waters).The arrival time of the surface circulation and mode water reaching the China Sea are 10–15 and 2–3 years,respectively.Before and after the FDNPP accident,the ^(137)Cs activity in the South China Sea and the Yellow Sea showed minor variation,whereas the ^(137)Cs activity in the East China Sea showed a slight increase.However,given the limited monitoring stations and short observation time,the impact of the FDNPP accident on the China Sea needs long-term monitoring and further evaluation.Meanwhile,we identified potential risks and future research directions of the FDNPP nuclear sewage disposal plan announced by the Japanese government.Furthermore,this study can provide a scientific basis for future research on Fukushima’s nuclear sewage discharge.