The Numerical experiment of distribution of anthropogenic radionuclides in the Japan Sea

Kawamura, Hideyuki  ; Ito, Toshimichi ; Kobayashi, Takuya ; Otosaka, Shigeyoshi  ; Hirose, Naoki*

Observation had been carried out to clarify distribution of anthropogenic radionuclides in the Japan Sea in the period between 1997 and 2002 by Japan Atomic Energy Agency. This study aims at reproducing the distribution of anthropogenic radionuclides with a numerical model and clarifying their movement in the Japan Sea. Deposition densities by global fallout are applied as boundary conditions for strontium 90 and cesium 137 at the sea surface. Numerical results show that concentration of strontium 90 and cesium 137 is compared with the observed one in the surface layer and the intermediate layer, although the concentration below 1000 m depth is quite low. More numerical experiments will be performed modifying parameters and boundary conditions of the numerical model in the future.