open access

https://doi.org/10.14943/bull.fish.66.3.99

https://hdl.handle.net/2115/64174

Generation Mechanism of the Anti-clockwise Nonlinear Eddy Street in the Region of the Soya Warm Current

日本語

self-excited oscillation

2016-12-27

北海道大学大学院水産科学研究院

北海道大学水産科学研究彙報

66(3)

99-114

The generation mechanism of anti-clockwise nonlinear eddy street along the Soya Warm Current is examined using the inflow-forced numerical model incorporating the simple shelf-slope topography. According to the conservation of potential vorticity, a strong positive vorticity is produced off the inflow entrance by vortex stretching as the water column is pushed out to deeper offshore. It rapidly grows up an isolated anti-clockwise circular eddy, i.e., a nonlinear eddy, during advection time traveling round the eddy. Therefore, this advection time controls the oscillated period, and each isolated eddy is periodically generated and stably advected downstream by the mean shear-flow. Such flow system accompanied by the eddy street is interpreted as the self-excited oscillation.

紀要論文

Version of Record

1346-1842

AA11547977