Back to Search
Start Over
Seasonal velocity variations over the entire Kuroshio path part I: data analysis and numerical experiments
- Source :
- Journal of Oceanography. 77:719-744
- Publication Year :
- 2021
- Publisher :
- Springer Science and Business Media LLC, 2021.
-
Abstract
- Herein, seasonal velocity variations from the sea surface to a depth of 1000 m over the entire Kuroshio path are investigated using satellite altimetry and reanalysis datasets. The data analysis results show that velocities in the upper layer (from 0 to approximately 500 m) reach a maximum in July and a minimum in autumn (October to November) or winter (December to February) with different tendencies in each region. However, those in the lower layer (> 500 m depth) show a reversed seasonal variation—reaching a maximum in winter—especially in the continental slope area from the east of Luzon Island to the east of the Ryukyu Islands chain, which is regarded as a route of the deeper Kuroshio flow. Using a realistic general circulation model, we performed numerical experiments to clarify the role of the local wind stress as the driving force in seasonal Kuroshio velocity variations in the upper layer. These experiments revealed that seasonal Kuroshio velocity variations in the upper layer are mainly caused by the local response to wind stress upon the current itself. These numerical results cannot be explained by conventional mechanisms, such as flow–topography interactions or coastal upwelling/downwelling. On the other hand, seasonal Kuroshio velocity variations in the lower layer can be explained by the Sverdrup theory, in which barotropic responses to the wind stress curl over the area west of the Izu–Ogasawara Ridge are responsible.
- Subjects :
- geography
geography.geographical_feature_category
010504 meteorology & atmospheric sciences
010505 oceanography
Continental shelf
Wind stress
Oceanography
Atmospheric sciences
01 natural sciences
Current (stream)
Ridge
Downwelling
Barotropic fluid
Sverdrup
Upwelling
Geology
0105 earth and related environmental sciences
Subjects
Details
- ISSN :
- 1573868X and 09168370
- Volume :
- 77
- Database :
- OpenAIRE
- Journal :
- Journal of Oceanography
- Accession number :
- edsair.doi...........cf16247cd1d626c7f6a355a35543d9e6