摘要
本文分析了扰动的频散效应对Ｒｏｓｓｂｙ波动量和热量输送的影响，分析指出：（１）频散效应是大气大尺度运动中扰动动能向平均动能转换（即能量逆转）的根本原因，也是扰动有效位能转化为扰动动能所必不可少的。
In this paper the influences of dispersion effects on momentum and heat transports by the Rossby waves are analyzed. It is shown that(a) The dispersion effects are the basic cause of energy inversion which represents that the eddies (or disturbances) give up kinetic energy to the mean flow inlarge-scale. motion. The dispersion effects are also absolutely necessary for the eddies(ro disturb.ances) to gain kinetic energy from available potential energy.(b) For the barotropic atmosphere, the suffiGient condition of energy inversionis that the characteristic width L(1) of horizontal shearing, /y, of basic flowis less than the critical width Lc≡|γ|/υ(υ and γ are the viscosity and dispersioncoefficients, respectively), For the baroclinic atmosphere, the sufficient condition totransform available potential energy into kinetic energy of perturbations is that thecharacteristic thickness D(2) of vertical variation, / , of mean potential tempo.rature is less than the critical depth Dc≡|κ|/k(k and κ are the thermal diffusivity and dispersion coefficients, respectively).The linear KdV-Burgers equation which is used to study the variation of basicflow is solved, too.
出处
《大气科学》
CSCD
北大核心
1994年第S1期837-846,共10页
Chinese Journal of Atmospheric Sciences
基金
国家攀登工程"非线性科学"的资助
关键词
扰动
ROSSBY波
耗散
频散
disturbance
Rossby waves
dissipation
dispersion.
