Temporal and Spatial Characteristics of Summer Extreme Precipitation in Eastern China and Possible Causalities

摘要: In the past decades, with increasing frequency of extreme weather and climate events, world has suffered huge losses. Based on NCEP/NCAR reanalysis data China regional precipitation provided by Meteorological Administration, events in eastern are defined relative threshold method, temporal spatial characteristics summer from 1961 to 2016 analyzed empirical orthogonal function (EOF), reverse distribution middle lower reaches Yangtze River south Indian Ocean warm pool is revealed influence. The results show that total amount concentrated Basin China. EOF1 decomposition reflects interannual oscillation time series corresponding significant characteristics. Pacific-Japan (PJ) teleconnection pattern a circulation system significantly affects spatial-temporal southern When PJ positive phase, anticyclone controls region, restrains convective activity, which decrease precipitation. anomalous southwest wind 30°N northerly north converge River. Combining sufficient water vapor carried airflow at edge anticyclone, it more conducive formation east propagating Kelvin wave an important reason for finally anomalies