摘要
Using observations and reanalysis data, this study investigates the interannual relationship between the winter Aleutian Low(AL) and the rainfall anomalies in the following summer in South China(SC). Results show that the winter AL is significantly positively(negatively) correlated with the SC rainfall anomalies in the following July(August). Specifically, SC rainfall anomalies have a tendency to be positive(negative) in July(August) when the preceding winter AL is stronger than normal. The winter AL-related atmospheric circulation anomalies in the following summer are also examined. When the winter AL is stronger, there is a significant anticyclonic(cyclonic) circulation anomaly over the subtropical western North Pacific in the following July(August). Southerly(northerly) wind anomalies to the west of this anomalous anticyclonic(cyclonic) circulation increase(decrease) the northward moisture transportation and contribute to the positive(negative) rainfall anomalies over SC in July(August). This study indicates that the AL in the preceding winter can be used as a potential predictor of the rainfall anomalies in the following July and August over SC.
Using observations and reanalysis data, this study investigates the interannual relationship between the winter Aleutian Low(AL) and the rainfall anomalies in the following summer in South China(SC). Results show that the winter AL is significantly positively(negatively) correlated with the SC rainfall anomalies in the following July(August). Specifically, SC rainfall anomalies have a tendency to be positive(negative) in July(August) when the preceding winter AL is stronger than normal. The winter AL-related atmospheric circulation anomalies in the following summer are also examined. When the winter AL is stronger, there is a significant anticyclonic(cyclonic) circulation anomaly over the subtropical western North Pacific in the following July(August). Southerly(northerly) wind anomalies to the west of this anomalous anticyclonic(cyclonic) circulation increase(decrease) the northward moisture transportation and contribute to the positive(negative) rainfall anomalies over SC in July(August). This study indicates that the AL in the preceding winter can be used as a potential predictor of the rainfall anomalies in the following July and August over SC.
基金
sponsored by the National Basic Research Program of China (Grant No. 2012CB955202)
