*Jun Nishioka^1,2, Hajime Obata³, Toru Hirawake^2,4, Youhei Yamashita⁵, Hiroshi Ogawa³, Ichiro Yasuda³ (1.Institute of low temperature sciences, Hokkaido University, 2.Arctic Research Center, Hokkaido University, 3.Atmosphere and Ocean Research Institute, The University of Tokyo, 4.Faculty of Fisheries Sciences, Hokkaido University, 5.Faculty of Environmental Earth Science, Hokkaido University)

*Toru Hirawake¹, Jun Nishioka², Hajime Obata³ (1.Faculty of Fisheries Sciences, Hokkaido University, 2.Institute of low temperature sciences, Hokkaido University, 3.Marine inorganic chemistry division, Atmosphere and Ocean Research Institute, University of Tokyo)

*Masahiro Maruo¹, Kazuma Tsuji², Tomoya Iwata³, Maki Oyagi⁴, Hajime Obata⁵ (1.Department of Ecosystem Studies, School of Environmental Science, The University of Shiga Prefecture, 2.Graduate School of EnvironmentalScience, The University of Shiga Prefecture, 3.Faculty of Life and Environmental Sciences, 4.Facluty of Environment and Infromation Science, 5.Atmosphere and Ocean Research Institute, The University of Tokyo)

*Ma. Teresa Escobar¹, Naoto Takahata¹, Kotaro Shirai¹, Takanori Kagoshima¹, Kentaro Tanaka¹, Hajime Obata¹, Yuji Sano¹ (1.Atmosphere and Ocean Research Institute University of Tokyo)

*Toshimasa Doi¹, Satoshi Osafune¹, Shuhei Masuda¹, Hajime Obata⁴, Kazuhiro Misumi³, Jun Nishioka² (1.Japan Agency for Marine-Earth Science and Technology, 2.Hokkaido University, 3.Central Research Institute of Electric Power Industry, 4. The University of Tokyo)

Tomohiro Shimazaki¹, *Hajime Obata¹, Hirofumi Tazoe², Shigeyoshi Otosaka¹, Shigenobu Takeda³ (1.Marine inorganic chemistry division, Atmosphere and Ocean Research Institute, University of Tokyo, 2.Institute of Radiation Emergency Medicine, Hirosaki University, Hirosaki, 3.Graduate School of Fisheries and Environmental Sciences, Nagasaki University )