Temporal and spatial variations of oceanic submesoscales induced by mixed layer instabilities in the Kuroshio Extension region

2015 Fiscal Year Final Research Report

• Project/Area Number: 25400473
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: Japan Agency for Marine-Earth Science and Technology
• Principal Investigator: SASAKI Hideharu 国立研究開発法人海洋研究開発機構, アプリケーションラボ, 主任研究員 (50359220)
• Co-Investigator(Kenkyū-buntansha): SASAI Yoshikazu 国立研究開発法人海洋研究開発機構, 地球環境観測研究開発センター, グループリーダ代理 (40419130)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 海洋循環場 / サブメソスケール / スケール間相互作用 / 時空間変動

Outline of Final Research Achievements

The outputs from the North Pacific high-resolution ocean simulation at horizontal resolution of 3km were used to investigate oceanic submesoscale structures with the scale from several km to several ten km. The simulation demonstrated seasonality of submesoscales, active in winter, in the Northwestern Pacific. The rich winter submesoscales are induced by the mixed layer instabilities. The temporal-spatial variations should be diagnostically observed by the high-resolution sea surface height based on the geostrophic theory. In addition, large inverse kinetic energy cascade from small scales to large scales were observed in winter, but not in summer. This result suggests large impact of submesoscales on temporal and spatial variations of larger scale oceanic fields.

Free Research Field

海洋物理