Circulation characteristics of EP and CP ENSO and their impacts on precipitation in South China

The results of both numerical simulations and diagnostic analyses show that in EP El Niño winters, there is a northerly wind on the lower troposphere of SC conducive to the southward movement of cold air to SC, converging in the south and diverging in the north, in agreement with the distribution of the precipitation anomalies. In the lower troposphere of SC in summer, an abnormal southwester is dominant, facilitating the movement of warm and moist air in the southwest toward SC, which is conducive to an increase in precipitation there. In EP La Niña winter, there is a southwester anomaly in the lower troposphere of SC, which is adverse to the southward movement of cold air from the north to SC, with the divergence field diverging in the south and converging in the north, in agreement with the distribution of precipitation anomalies in this region. In EP La Niña summer, there is a northeaster anomaly in SC that is in the water vapor convergence area, which is conducive to precipitation in SC. In CP El Niño summer. There are northerly winds over SC and an anomalous cyclone over the western Pacific and South China Sea, which was beneficial to precipitation.