Influence of Global Warming to Variation of Extreme Temperature of Ningxia in Recent 40 Years

Climate change in Ningxia on background of global warming was analyzed based on the meteorological data in recent 40 years.The variation of annual mean temperature and extreme temperature were studied.Results show that: ①The air temperature of Ningxia increased continuously in recent 40 years,especially quickened after 1986 and with a higher warming extent than the national average.②The extreme high and low annual temperature continuously increased in fluctuation,and the increasing extent of annual extreme low temperature was obviously higher than that of the annual extreme high temperature.③The variation of seasonal extreme high and low temperature was asymmetric,the increasing extent of extreme high temperature was higher than that of the extreme low temperature in autumn,but it was inverse in spring,summer and winter,especially in summer.④The monthly extreme high and low temperature increased.