对热带不稳定海气相互作用模式的改进

AN IMPROVEMENT ON THE TROPICAL UNSTABLE AIR-SEA INTERACTION MODEL

中文关键词:  热带  海气相互作用  模式

英文关键词:Tropical belt  Air-sea interaction  Model

中文摘要:

      对以前提出的热带海气相互作用模式^[1]风应力的参数化作了改进。和以前一样,在这个耦合模式中,滤去了大气和海洋中的重力惯性波,只保留了向西传播的Rossby波。但经过海气相互作用后,理论分析指出,在耦合模式中存在着快的和慢的两类波动。快波频率的实部、即其相速度是向西传的,并接近于未经海气相互作用时大气中Rossby波的频率;而慢波的性质和以前的结果类似,短波部分是向西传的,长波部分向东传,东传波的临界波数随海气相互作用增强向短波部分位移。与以前结果不同的是,除一个慢波不稳定增长外,另一个快波在长波部分也是不稳定增长的。海气相互作用越强,不稳定增长率和不稳定波所出现的波段范围越大。另外,本文的研究结果还指出,高频和低频不稳定波产生的物理条件是不一样的。

英文摘要:

      An improvement on the parametrization of wind stress is made to the tropical air-sea interaction model formerly proposed by Chao and Zhang: In this air-sea coupled model, the inertial-gravity waves are filtered out and only the equatorial Rossby waves are reserved in both the atmosphere and the ocean. Results indicate that after the air-sea interaction, two kinds of waves appear in the coupled model, one is of high-frequency and another is of low-frequency. The properties of the low-frequency waves are similar to those in Ref. [1]. The different results from those in Ref. [1] are that besides the low-frequency unstable waves the high-frequency waves are unstable in the scope of comparatively long wavelengths. The stronger the air-sea interaction, the larger the amplifying rate and wider the scope in which the unstable high-frequency waves appear. This paper also proves that the physical condidons for the producing of the low-frequency and high-frequency unstable waves are different.