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Fukushima-derived radiocesium in the western North Pacific in 2014.

ABSTRACT: In 2014, we measured activity concentration of radiocesium in the western North Pacific Ocean. In the north of Kuroshio Front high activity concentration of Fukushima-derived radiocesium in surface mixed layer in 2012 had been transported eastward by 2014. In the south of the front we found a radiocesium subsurface maximum in 200-600 m depth, which was similar to that observed in 2012. The subsurface maximum spread southward from 18°N to 15°N between 2012 and 2014, which suggests spreading of Fukushima-derived radiocesium into the whole western subtropical area by 2014 due to formation and subduction of the subtropical mode water.

SUBMITTER: Kumamoto Y

PROVIDER: S-EPMC5306276 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Fukushima-derived radiocesium in the western North Pacific in 2014.

Kumamoto Yuichiro Y Aoyama Michio M Hamajima Yasunori Y Nagai Hisao H Yamagata Takeyasu T Kawai Yoshimi Y Oka Eitarou E Yamaguchi Atsushi A Imai Keiri K Murata Akihiko A

Journal of radioanalytical and nuclear chemistry 20161003 2

In 2014, we measured activity concentration of radiocesium in the western North Pacific Ocean. In the north of Kuroshio Front high activity concentration of Fukushima-derived radiocesium in surface mixed layer in 2012 had been transported eastward by 2014. In the south of the front we found a radiocesium subsurface maximum in 200-600 m depth, which was similar to that observed in 2012. The subsurface maximum spread southward from 18°N to 15°N between 2012 and 2014, which suggests spreading of Fu ...[more]

PMID: 28250546

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