关键词: 南极绕极波;海面气压;波动系统;行波;驻波;传播

Abstract:

The Antarctic circumpolar wave(ACW) has become a focus of the air-sea coupled Southern Ocean study since 1996,when it was discovered as an air-sea coupled interannual signal propagating eastward in the region of the Antarctic Circumpolar Current(ACC).In order to analyze the mechanism of discontinuity along the latitudinal propagation,a new idea that ACW is a system with a traveling wave in the Southern Pacific and Atlantic Ocean and with a concurrent standing wave in the southern Indian Ocean is proposed in this paper.Based on the ideal wave principle,we retrieve the average wave parameters of ACW using a non-linear approximation method,where we find that the standing part and the traveling part possess similar radius frequency,proving their belonging to an integral system.We also give the latitudinal distribution of wave speed from what we could tell the reason for steady propagation during that period.The spatial distribution of the propagation reveals complex process with variant spatial and temporal scales——the ENSO scale oscillation greatly impacts on the traveling process,while the result south of Australia indicates little connection between the Indian Ocean and the Pacific,which may be blocked by the vibration west of Pacific.The advective effect of ACC on the propagation process should be examined clearly through dynamical method.