He received his B.S. in Earth and Planetary Physics, and M.S. and Ph.D. in Physical Oceanography from the University of Tokyo. One of his major research focuses is the characteristics of mesoscale eddies in the Kuroshio/Oyashio area, and he has been studied them comprehensively through observations, data analysis and numerical experiments. His recent research interests extend from mesoscale to submesoscale processes, and their influences onto the ecosystem variability.