Dynamics of self-propelling vortex pairs

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K03655
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 17020:Atmospheric and hydrospheric sciences-related
• Research Institution: Hokkaido University
• Principal Investigator: Nakamura Tomohiro 北海道大学, 低温科学研究所, 講師 (60400008)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 海洋物理 / 海洋 / 渦 / 渦対 / 物質輸送 / 河川水 / 潮流

Outline of Final Research Achievements

Coasts serve as the interface between land and open oceans, with many terrestrial and anthropogenic substances spreading from coasts to open oceans. However, the processes of transport from coasts to open oceans are largely unknown, and one of such processes is 'vortex pairs,' which effectively induce transport. In this study, we showed (1) effects of density stratification and topography on the formation and evolution of vortex pairs, the behavior of vortex pairs accompanied by small vortices, and the formation of vortex pairs accompanying river water discharge. The results obtained would contribute to the better understanding and improvement of modeling of water and substance transport from rivers and coasts to the open ocean.

Free Research Field

海洋物理

Academic Significance and Societal Importance of the Research Achievements

本課題は、沿岸から外洋へ水・物質を効果的に輸送する「渦対」について研究し、河川水流出により渦対が形成されることを明らかにした。得られた知見は、海洋物理学・流体力学の発展に加えて、河川・沿岸から外洋への海水・物質輸送の解明・モデリングの向上に資する。河川から供給された淡水や物質が外洋でどこまで広がるかは、海洋の子午面循環や栄養物質循環・基礎生産を左右することから、海洋内炭素貯留への寄与を介して気候変動に影響する。さらに、近海の栄養物質循環や基礎生産は水産業や沿岸域の水質維持にも影響する。