Temporal and spatial changes of extreme temperatures in China during 1961～2008

Based on the annual average temperature,daily maximum and minimum temperature data of eight representative meteorological stations during the period of 1961～2008,we mainly studied the spatial and temporal variation and trends for extreme temperatures.The results showed that the annual average temperature,extreme maximum and extreme minimum temperatures exhibited a significant upward trend in recent 50 years;Increase in extreme minimum temperature was greater than the extreme maximum temperature,extreme temperature difference tended to ease;After 1970s,more anomalous cold and warm weathers occurred;In addition to Western,Northwest and East China,the number of days with daily maximum temperature over 35℃ tended to increase;The number of days with daily minimum temperature below 0℃ significantly reduced;Meanwhile,the frost-free days of Qinghai-Tibet Plateau increased significantly.