Study of properties of the mixed layer and deep convection in a polar ocean

2014 Fiscal Year Final Research Report

• Project/Area Number: 24340112
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: Kyoto University
• Principal Investigator: AKITOMO Kazunori 京都大学, 理学(系)研究科(研究院), 教授 (10222530)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 深層対流 / 非線形状態方程式 / 混合層

Outline of Final Research Achievements

Stability of the water column and properties of deep convection have been investigated by experiments with a model resolving turbulent motion. Under sea-ice cover, while convective motion is suppressed in the mixed layer by Earth rotation and larger background viscosity and diffusivity, destabilization of the water column is hastened. This is partly because the negative feedback mechanism which prevents the mixed layer from being densified becomes less active and partly because the enhanced mixing at the base of the mixed layer causes densification due to the cabbeling effect. When viscosity and diffusivity increases by the order of one, overturning of the water column is hastened by more than one month, suggesting significant effects on the long-term global deep circulation.

Free Research Field

海洋物理学