大气低频振荡的数值模拟

A Numerical Simulation of Low Frequency Oscillations in the Atmosphere

本文利用ＩＡＰＧＣＭ积分结果中１０年候平均资料，研究了模式大气中的低频振荡现象。结果表明，该模式能相当逼真地模拟出低频振荡的地理分布、垂直结构和传播过程的主要特征，因而低频振荡是大气本身所固有的一种现象。而流场与大气加热场之间在低频域内的相关分析则证实了大气加热对低频振荡的产生起重要的作用，其中最重要的因子是水汽潜热的释放。

In this paper, low frequency oscillations (LFO) in the model atmosphere are studied using the 10-year pentad-mean data simulated by the IAP GCM. The results show that the model can simulate the characteristic features of geographical distribution, vertical structure and propagation of LFO with high accuracy. Threrefore, LFO is an intrisic phenomenon in the atmosphere. Correlation analysis between the wind and heating in the low frequency domain shows that the atmospheric heating is important to the formation of LFO, the key factor is the latent heat release of moisture.