南海季风低压发生发展机制的探讨

根据FGGEⅢB资料,对发生在1979年8月中旬的一次南海季风低压过程,利用ω方程和Kuo(1974)的积云对流参数化方案进行了诊断研究.结果表明:决定南海季风低压发生发展的物理过程是潜热加热,尤以积云对流的作用最显著,温度平流和涡度平流也起一定作用,其它物理因子贡献较小.南海季风低压是通过积云对流和大尺度环境场的反馈作用而发展增强的,可认为,CISK机制是低压发生发展的主要机制.

Probing into the Mechanism of Generation and Development of the Monsoon Depression over South China Sea

The diagnostic analyses are made on a case of Monsoon Depression over South China Sea in the Middle of Aug., 1979. The FGGE3B data, the diagnostic balance model and the cumulus parameterization scheme are used. The results show that the decisive physical process to the genesis and development of the depression is latent heating, among which the cumulus convection heating is the largest, meanwhile the temperature advection and vorticity advection are also obvious. The contribution of the other terms is small. The development of the depression attributes to the feedback between cumulus convection and the largescale environment field. The genesis and development of the depression can be explained by CISK mechanism.