Marine Environment Research Department, Korea Institute of Ocean Science and Technology, Busan, Republic of Korea.
Ocean Circulation & Climate Research Department, Korea Institute of Ocean Science and Technology, Busan, Republic of Korea.
Mar Pollut Bull. 2023 Oct;195:115463. doi: 10.1016/j.marpolbul.2023.115463. Epub 2023 Sep 1.
This study investigates the dispersion behavior of Cs and evaluates its origin (atmospheric deposition or direct ocean release) from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident using a Lagrangian particle tracking model. The ocean circulation fields based on the Modular Ocean Model Version 5 (MOM5) were adopted for the simulation. The MOM5 results represented the formation and migration of subtropical mode water (STMW) comparable with observations and reanalysis data. Particularly, anticyclonic eddies south of the Kuroshio extension promoted surface mixing over 300 m in the cooling season. The particle tracking simulation reproduced well the maximum subsurface activity between 142 and 146°E, where STMW is deep owing to anticyclonic eddies, compared to the activity found via measurements conducted around 149°E in the winter of 2012. It also demonstrated that the Cs of the tropical and subtropical regions (10-35°N, 142-146°E) in the winter of 2012 almost entirely originated from atmospheric deposition.
本研究采用拉格朗日粒子轨迹模型，调查了 Cs 的扩散行为，并评估了其源自福岛第一核电站（FDNPP）事故的来源（大气沉降或直接海洋释放）。该研究采用基于模式海洋模型版本 5（MOM5）的海洋环流场进行模拟。MOM5 的模拟结果与观测和再分析数据一致，很好地再现了亚热带模态水（STMW）的形成和迁移。特别是，黑潮延伸南部的反气旋性涡旋促进了冷却季节中超过 300 米的表面混合。粒子轨迹模拟很好地再现了在 142-146°E 之间的最大次表层活动，由于反气旋性涡旋的存在，STMW 很深，与 2012 年冬季在 149°E 附近进行的测量结果相比。它还表明，2012 年冬季热带和亚热带地区（10-35°N，142-146°E）的 Cs 几乎完全来自大气沉降。
