Winter Temperature Anomalies in South China and Its Relation to ENSO
Based on the monthly temperature data of 192 observational stations in South China, NCEP/NCAR reanalysis monthly temperature data and ENSO monitoring data by NCC, the relationship between winter temperature in South China and ENSO is studied by using the methods of correlation analysis, composition analysis and so on. The results show that the response of the winter temperature in South China to La Ni〖AKn~D〗a event is more obvious than to El Ni〖AKn~D〗o event. In La Ni〖AKn~D〗a year, the winter temperature in South China is lower than in normal years. The significantly low temperature appears in extremely strong La Ni〖AKn~D〗a years, but the temperature is high obviously in central pattern La Ni〖AKn~D〗a events. The winter temperature in South China is mainly lower (higher) than that in normal years when La Ni〖AKn~D〗a (El Ni〖AKn~D〗o) event is in east pattern, and the peak months of Nino SSTA are in autumn and winter. In La Ni〖AKn~D〗a years, there is an abnormal cyclone circulation in the Pacific subtropical high and abnormal north wind in the low troposphere. North Pacific high, Ural Mountains high ridge and the south of East Asia trough also become strong, the West Pacific subtropical high becomes weak in the middle troposphere. The meridional circulation in middle high latitude in East Asia is evident. East Asian winter monsoon is strong in case of La Ni〖AKn~D〗a events, the winter temperature in most regions of China including South China is lower than that in normal years, and vice versa. There are significant interdecadal differences of the effect of El Ni〖AKn~D〗o event on the winter temperature in South China. SST variation obviously corresponding to interdecadal variation of the winter temperature in South China is found in North Pacific, and the relationship between the variation and ENSO is not obvious.