中、低纬太平洋ARGO测站Rossby内波垂直模态的数值计算

针对中、低纬太平洋ARGO测站的4个实际层结个例，计算了无背景流下准地转海洋Rossby内波的垂直模态。结果表明，海水层结垂直方向的不均匀和跃层的存在，使该垂直模态的波型发生了歪曲变形，致使其偏离了余弦波：跃层越强，这种变形也越大：层结最强的层次对应着最大的波动振幅，多极值的层结对应着多个极大振幅：该内波垂直结构函数的零点随模态序数依次递增，且其零点在海水层结较强的层次要比较弱的层次密集。

Numerical Calculation of Vertical Modes of Rossby Internal Wave for ARGO Station in the Mid-low-Latitude Pacific Ocean

For the four cases of oceanic stratification from Argo stations in the mid-low- latitude Pacific Ocean, vertical modes of Rossby internal wave in quasi-geostrophic ocean without basic current are calculated. The results show that, because of the nonhomogeneous of sea density and the existence of pycnocline, the wave shape of vertical modes is distorted, that is to say, it deflects from the cosine wave. And the stronger the stratification is, the more obvious the distortion is. Pycnocline corresponds to the extremum amplitude. Multiple extremum stratification corresponds to the multiple maximum amplitude. The the zero-point number of the vertical structure function increases with the baroclinic mode sequence, and the zero-points at the layer where the stratification is strong are denser than that at the layer where the stratification is weak.