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利用一个快速的海洋一大气耦合模式(FOAM)在青藏地区高、低两种地形条件下进行了一组改变地球轨道参数(岁差和地轴倾角)的数值模拟试验.探讨了亚洲季风区轨道尺度气候变率对青藏高原隆升的响应.试验结果表明:当因轨道参数变化引起北半球夏季日射增强(减弱)时,由北非至东亚的夏季风北界一带季风降水会显著增加(减少).而且,在高地形情况下以降水为主要特征的亚洲夏季风对同样日射强迫的响应比在低地形情况下的响应要强烈得多.上述季风降水的变化与大气环流的改变密切相关.这些耦合数值模拟结果为中国黄土记录的上新世期间东亚季风轨道尺度气候变率的显著增加提供了一种机制的理解. “,”A fast Ocean-Atmosphere Model was applied to simulate the Asian monsoon changes on conditions of high mountains (HM) and low mountains (LM) in the present-day Tibetan Plateau region with Earth's orbital parameters (precession and obliquity) variations. The experiments show that, when orbital changes induced boreal summer insolation increases (decreases), the monsoonal precipitation notably increases (decreases) as well along regions from North Africa to East Asia, which are northernmost regions influenced by summer monsoon. Furthermore, the Asian monsoon, mainly characterized by precipitation, has much greater response to insolation forcing in HM scenario than that in LM case. Such monsoonal rainfall variations are closely related to atmosphere circulation changes. The simulated results from this coupled ocean-atmosphere model may provide us with a new perspective to understand the mechanism of dramatically increased East Asian monsoon variability on the orbital time scale during Pliocene, as recorded in Chinese loess-paleosol sequences.