The Impact of Autumn Antarctic Oscillation (AAO) on Winter Precipitation in Southern China

With station-based and reanalysis datasets, this research documents the negative correlation between the autumn Antarctic Oscillation (AAO) and winter precipitation in southern China. In positive (negative) AAO anomaly years, the significantly stronger (weaker) subtropical westerly jet, western European trough, East Asia trough and Ural ridge, the weaker (stronger) the Aleutian low, southern trough and western Pacific subtropical high. The inactive (active) disturbance along the southwest jet and the abnormal northerly wind (southerly wind), which prevails in most regions of China with a weak positive anomaly OLR, all lead to the decreasing (increasing) southern China rainfall. Two meridional teleconnection patterns exist with one along East Asia-the Southern Hemisphere high latitudes and the other over the whole Pacific from south to north. The convection over the region of the maritime continent may serve as a bridge linking the autumn AAO and winter precipitation in southern China. Therefore, the abnormal autumn AAO could possibly have significant denotative meaning on forecast of winter precipitation in southern China.