基本流纬向切变下的稳定辐射斜压位涡
Stable Radiation Baroclinic Potential Vortices Under Basic Flow Zonal Shear
刘楠 1宋健1
作者信息
- 1. 内蒙古工业大学 理学院,呼和浩特 010051
- 折叠
摘要
在大尺度垂直剪切中,嵌入一类新的、稳定传播的斜压涡旋,它辐射的Rossby波没有衰减.通过考虑Beta平面上的两层模型为基础,利用纬向二次剪切流与稳定辐射斜压流体之间的色散关系变化,进行数值模拟,得出了二次剪切流对稳定辐射斜压位涡(potential vorticity,PV)不稳定性的影响;同时涡旋产生的Rossby波,引起经向涡旋的传播及其他相干的热流;对于亚热带海洋向西流,随纬度变化,通过三角函数近似解,给出相应Bessel函数数值解,得到二次剪切流使得上层PV梯度的减少,持续延长了涡旋的寿命.
Abstract
In large-scale vertical shear,a new type of stably propagating baroclinic vortex was embedded,to radiate Rossby waves without attenuation.Numerical simulations were carried out based on the 2-layer model in the beta-effect plane,by means of the variation of the dispersion relation between the zonal quadratic shear flow and the stable radiation of the baroclinic fluid.The effect of the zonal quadratic shear flow on the baroclin-ic potential vortex instability of steady radiation,was derived.At the same time,the Rossby waves generated by the vortices cause the propagation of the meridional vortices and other coherent heat flows.For the west-ward flow of the subtropical ocean,with the latitude change,the approximate solution of the trigonometric function gives the numerical solution of the relevant Bessel function.The results show that,the quadratic shear flow reduces the PV gradient in the upper layer and continues to extend the life of the vortex.
关键词
二次剪切流/稳定辐射/斜压涡旋Key words
quadratic shear flow/stable radiation/baroclinic vortex引用本文复制引用
基金项目
国家自然科学基金(42275052)
内蒙古自治区高等学校科学研究重点项目(NJZZ23087)
内蒙古自治区研究生科研创新项目(JY20220388)
出版年
2024
国家科技期刊平台
NSTL
维普
万方数据