本文给出了一个缩减大气环流模式自由度的新方法,理论基础是强迫耗散非线性系统的高维相空间将演化到一个低维的吸引子上.具体方法是对模式的一个现实作经验正交函数(EOF)分解,从而找出支撑吸引子的少数自由度,并以此为基底获得简化模型.用一个理论模型进行了数值模拟试验,试验证实了此方法的可行性和有效性. This paper presents a new method to reduce the degree of freedom of the general circulation model, based on the fact that the high-dimensional phase space of forced dissipative nonlinear systems will evolve onto a low-dimensional attractor with concrete experience as a realistic model (EOF) decomposition to find out a few degrees of freedom supporting the attractor, and based on this, a simplified model was obtained.A theoretical model was used to do the numerical simulation and the experiment proved the feasibility and effectiveness of this method.