THE INTERACTION BETWEEN DISTURBANCE AND ZONAL MEAN FLOW IN “JUNE SUDDEN CHANGE”

Using Eliassen-Palm theory and its diagnostic method, in this paper, we analyzed and discussed the dynamical mechanism of the interaction between disturbance and zonal mean flow in the sudden change of the general circulation in the Northern Hemisphere in early summer of 1982, indicating that the northward jump of subtropic jet stream is closely related to the enhanced transport of mid-latitude disturbance energy to the subtropic tropopause. However,the direction of the transport is conditioned by the structure of zonal mean flow. During this episode, the response of the change of zonal mean flow to the disturbance transport is very quick and evident. As to the suddenness of the change of the circulation, the role of the disturbance forcing is critical.