Using the FGGE-III(b) data of 1979, this paper analyzed the spectrum structure of the total energy, the apparent heat source and the moisture sink over the Asian summer monsoon areas. The spectrum distribution for different periods and the propagation of oscillations are investigated. It is found that these distribution and propagation have their synoptic and climatologic meaning, when they are compared with the summer monsoon circulation.The results also show that the quasi-40 days oscillation is the most significant one in these areas. The distribution of spectrum variance and the propagation pattern indicate the independence of the monsoon systems over India, the Bay of Bengal, the South China Sea and the continental East Asia. Different monsoon systems are dominant in different areas, respectively. For instance, the midlatitude system is dominant in north China north of the Yangtze River, the coastal area in south China is controlled by the monsoon of the South China Sea, and the southwest China, such as Yunnan, is mainly inflerenced by the monsoon of the Bay of Bengal. Near the equator, there are some passages for propagating oscillations of the total energy and moisture, which are consistent with those for the northward cross-equatorial flows. However, such a feature does not belong to the oscillation of apparent heat source of the atmosphere, which makes its contribution mainly to the quasi-stable state of the atmospheric general circulation.
