ANALYSIS OF THE SPATIOTEMPORAL VARIATION CHARACTERISTICS OF MAIN EXTREME CLIMATE INDICES IN SICHUAN PROVINCE OF CHINA FROM 1968 TO 2017

With an increasing trend in global warming, extreme weather and a variety of related climate events frequently occur in the Southwestern China In this research, we analyzed daily maximum and minimum temperatures, and daily precipitation data of 39 meteorological stations in the Sichuan Province between the years of 1968 and 2017. Nineteen different indices representing extreme climate change were selected, and linear regression analysis, Mann-Kendall mutation test, sliding T test, wavelet analysis and R/S analysis were applied. According to the results, we concluded that: (1) most extreme cold indices showed a decreasing trend, while the extreme warm indices displayed an increasing trend. There was no significant interannual variation for extreme precipitation indices. (2) Most extreme temperature indices presented no significant mutation years, and the significant periods were mainly 2-6 years long. The mutation years of heavy and very heavy precipitation events mainly appeared in the 1980 and the early 21st century, and the significant periods of most extreme precipitation indices were 2-7 years long. (3) As shown by the Hurst exponent analysis and interannual variation trends, it is very likely that the extreme temperature and extreme precipitation events in the Sichuan Province will increase in the future.