*Yuichi Nishimura¹, Yasuhiro Takashimizu², Daisuke Sugawara³, Takafumi Enya⁴, Takashi Chiba⁵, Ryo Nakanishi⁶, Alexander Shishkin⁷, Alexey Gorbunov⁸, Victor Kaistrenko⁸, Asuka Takahashi⁹, Hiroki Muramatsu¹⁰, Yasuyuki Kawazoe¹¹, Naofumi Takamatsu¹¹ (1.Graduate School of Science, Hokkaido University, 2.Institute of Humanities, Social Sciences and Education, Niigata University, 3.Museum of Natural and Environmental History, Shizuoka, 4.Hokkaido Museum, 5.Faculty of Bioresource Sciences, Akita Prefectural University, 6.Hokkaido Education University, 7.Shikotan Geophysical Observatory, 8.Institute of Marine Geology and Geophysics, Russian Academy of Sciences, 9.Japan Meteorological Agency, 10.Geospatial Information Authority of Japan, 11.Ministry of Education, Culture, Sports, Science and Technology)