摘要
From quasi-geostrophic vorticity equation, we simulate the formation of ocean shear wave in western boundary strong current area with the pseudospectral method, and idealize the initial velocity into hyperbolictangent velocity profile, with the unsteady little perturbation developed by means of getting energy from meanmotion. The change of isovorticity shows two vortexes merging or splitting between them. The evolving processof material lines reflects cold water's invading and warm water's turning, which is agreeable to satellite photograph.Nonlinear effect makes a new energy distribution in all kinds of motion scale. One important phenomenon is that Reynolds stress will change its sign when the perturbation amplitude is large enough.
From quasi-geostrophic vorticity equation, we simulate the formation of ocean shear wave in western boundary strong current area with the pseudospectral method, and idealize the initial velocity into hyperbolictangent velocity profile, with the unsteady little perturbation developed by means of getting energy from meanmotion. The change of isovorticity shows two vortexes merging or splitting between them. The evolving processof material lines reflects cold water's invading and warm water's turning, which is agreeable to satellite photograph.Nonlinear effect makes a new energy distribution in all kinds of motion scale. One important phenomenon is that Reynolds stress will change its sign when the perturbation amplitude is large enough.
