Key Laboratory of Meteorological Disaster;
Ministry of Education(KLME)/Joint Intemational Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD);
Nanjing University of Information Science&Technology;
Nanjing 210044 China;
Northern and Southern Hemispheres; circulation variations; covariation mode; climate anomaly; ENSO;