摘要
On the basis of studying wave package propagation, this paper investigated the relationship between high frequency wave package propagation and transient waves＇ evolvement or the subtropical high＇s latitudinal movement. The results showed that during winter the lifetime of wave package was longer and usually persisted for 7-10 days with a propagating speed of 2-10 m s-l. Usually they propagated southeastward at the beginning, then turned to northeast. During summer the lifetime and intensity of wave package became shorter and weaker. It availed development （attenuation） of troughs when the strong wave package center was intensified （weakened） which overlapped with trough. If strong wave package center kept overlapping with ridge, the ridge would abate later in a few days. Obvious jumping northward （retreating southward） processes of Western Pacific subtropical high （WPSH） were （not） usually related to strong wave package centers located at South China Sea area （South Asia area and Temperate Zone） for 5 days or longer. After two seasonal jumping processes, there were persisting strong wave package centers for 5 days or longer. WPSH retreating processes were also related to activities of strong wave package centers over South Asian area and temperate area as well as the strong wave package centers of typhoon, and all these centers persisted for 5 days or longer.
On the basis of studying wave package propagation, this paper investigated the relationship between high frequency wave package propagation and transient waves＇ evolvement or the subtropical high＇s latitudinal movement. The results showed that during winter the lifetime of wave package was longer and usually persisted for 7-10 days with a propagating speed of 2-10 m s-l. Usually they propagated southeastward at the beginning, then turned to northeast. During summer the lifetime and intensity of wave package became shorter and weaker. It availed development （attenuation） of troughs when the strong wave package center was intensified （weakened） which overlapped with trough. If strong wave package center kept overlapping with ridge, the ridge would abate later in a few days. Obvious jumping northward （retreating southward） processes of Western Pacific subtropical high （WPSH） were （not） usually related to strong wave package centers located at South China Sea area （South Asia area and Temperate Zone） for 5 days or longer. After two seasonal jumping processes, there were persisting strong wave package centers for 5 days or longer. WPSH retreating processes were also related to activities of strong wave package centers over South Asian area and temperate area as well as the strong wave package centers of typhoon, and all these centers persisted for 5 days or longer.
基金
Supported jointly by the National Natural Science Foundation of China under Grant No.40675056
Open Research Fund in Laboratory for Climate Studies of China Meteorological Administration under Grant No.LCS-2006-01.
