Near-inertial waves and diapycnal mixing in the Kuroshio and its origin

Research Summary

Previous studies have suggested that the Kuroshio origin is frequently accompanied by banded near-inertial shear. It is however unclear how these near-inertial waves are generated and affect diapycnal mixing. In this study, mechanisms of these wave generations, their propagations, and dissipations are investigated with high-resolution microstructure measurements and numerical simulations. The objectives of this study is to quantify (1) the energy being transferred from the Kuroshio current in its origin to near-inertial waves, and (2) the rate of the near-inertial wave energy dissipation, and to (3) evaluate the impacts of associated diapycnal mixing on the nutrient supply.

Fig. 1：Schematics of tow-yo microstructure observations in the Kuroshio origin regions proposed by this research.

Fig. 1：Schematics of tow-yo microstructure observations in the Kuroshio origin regions proposed by this research.

Principal Investigator：

Takeyoshi Nagai

Assistant Professor, Tokyo University of Marine Science and Technology, Department of Ocean Sciences, Physical Oceanography

Collaborator：

Ryuichiro Inoue

Senior Scientist, JAMSTEC, Physical Oceanography

Collaborator：

Hirohiko Nakamura

Associate Professor, Faculty of Fisheries, Kagoshima University, Physical Oceanography