Articles | Volume 14, issue 4
https://doi.org/10.5194/os-14-813-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-14-813-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
24 Aug 2018
Research article |
| 24 Aug 2018
| 24 Aug 2018
Transport of FNPP1-derived radiocaesium from subtropical mode water in the western North Pacific Ocean to the Sea of Japan
Yayoi Inomata
CORRESPONDING AUTHOR
Institute of Nature and Environmental Technology, Kanazawa University,
Kanazawa, 920-1156, Japan
Michio Aoyama
Institute of Environmental Radioactivity, Fukushima University,
Fukushima, 960-1296, Japan
Yasunori Hamajima
Institute of Nature and Environmental Technology, Kanazawa University,
Kanazawa, 920-1156, Japan
Masatoshi Yamada
Institute of Radiation Emergency Medicine, Hirosaki University,
Hirosaki, 036-8564, Japan
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Short summary
Analysing increased 137Cs and 134Cs / 137Cs ratio derived from the Fukushima Nuclear Power Plant accident in the Sea of Japan and its marginal sea, we found a rapid transport process associated with subduction in the subtropical mode water (STMW) formation region and obduction in the north East China Sea. The integrated amount of FNPP1 137Cs entering the Sea of Japan until 2016 was estimated to be 0.21 ± 0.03 PBq, which corresponds to 5.1 (3.4–8.0) % of the total amount of FNPP1 137Cs in the STMW.
Analysing increased 137Cs and 134Cs / 137Cs ratio derived from the Fukushima Nuclear Power Plant...
