2011 Fiscal Year Final Research Report
An estimation of oceanic eddy heat transport in a high resolution Ocean General Circulation Model
| Project/Area Number |
21740336
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Meteorology/Physical oceanography/Hydrology
|
|---|
| Research Institution | Hokkaido University |
|---|
Principal Investigator |
AOKI Kunihiro 北海道大学, 大学院・地球環境科学研究院, 博士研究員 (70507178)
|
|---|
| Project Period (FY) |
2009 – 2011
|
| Keywords | 海洋中規模渦 / 熱輸送 / 高解像度海洋数値シミュレーション |
|---|
| Research Abstract |
The present study, for the first time, estimates meridional heat transport induced by oceanic mesoscale variability such as mesoscale eddy in the World Ocean using a global eddy-resolving Ocean General Circulation Model(OGCM) conducted by the Earth Simulator. Poleward eddy heat transports are generally predominant for the Western Boundary Currents and the Antarctic Circumpolar Current, and along with equatorward eddy heat transport in the equatorial region, as similar to the results from previous studies with coarser resolution OGCMs. Such a significant poleward eddy heat transport in mid-latitude oceans suggests that the eddies act to weaken strong meridional background temperature gradients as expected from the linear baroclinic instability theory. However, interestingly, especially for the Kuroshio Extention and the Gulf Stream, equatorward eddy heat transport occurs in subsurface layer along the southern frank of these currents. The dominant mechanism of the equatorward eddy heat transport is different between these currents. For the Kuroshio Extension, warm water originally distributed on the current path is advected equatorward by equatorward current in the event of equatorward meandaring of the current path. For the Gulf Stream, warm eddies with circular shape formed on the Gulf Stream migrates equatorward along eastern rim of the southern recirculation gyre.
|
