Instability analysis of three-dimensional ocean shear waves

Based on the continuously stratified quasi-geostrophic vorticity equation, the present paper analyses the instability of three-dimensional shear waves.The cause that most shear waves occur on the shelfside of strong currens near the west boundaries of the oceans is presented.The growth rate of small perturbations relies on the stratification charactern, and a maximum value of growth rate exists for certain stratification.