Correlation analysis of rainfall and ENSO in Shanxi

Based on the monthly rainfall data, the CPC(Climate Prediction Center) Southern Oscillation Index(SOI) and the monthly Pacific SST(Sea Surface Temperature) of NOAA(The National Oceanic and Atmospheric Administration) at 38 meteorological stations in Shanxi, trend analysis and correlation analysis methods were used to analyze the response of the seasonal rainfall during recent 56 years to ENSO events in this province. The results are shown as follows:(1) In La Nina years, the annual, autumn and winter rainfall had increasing trends, while the spring and summer rainfall decreased. In El Nino years, the spring rainfall had increasing trends, but the annual, summer, autumn and winter rainfall decreased. In the year after a La Nina event, the winter rainfall would increase, but the annual, spring, summer and autumn rainfall decreased.(2) The annual rainfall showed that there was a positive correlation between Pacific SST of the previous year in Nino 3 and 4 regions and annual rainfall in Shanxi.If Pacific SST of the previous year was higher(or lower), the rainfall in Shanxi would be correspondingly more(or less) than that in a normal year. The annual rainfall was negatively correlated to Pacific SST of the same year in Nino 3 region. If Pacific SST of a year is higher(or lower), the annual rainfall in Shanxi would be less(or more) than that in a normal year.(3)SOI was significantly and negatively correlated to the rainfall trend index of most parts of Shanxi province. The correlation coefficients in some parts of the central-western and easternnorthern Shanx were over-0.5, and the monthly rainfall of these areas would be less(or more)if SOI was positive(or negative).