Asymmetrical Change of Maximum Temperature and Minimum Temperature in Sichuan from 1960 to 2010

The spatial and temporal change of maximum and minimum temperatures and diurnal temperature range were analyzed based on the temperature data of 138 meteorological stations in Sichuan province from 1960 to 2010.The results showed that annual average maximum and minimum temperatures increased non-symmetrically,the maximum and minimum temperatures changed at the rate of 0.131℃/10a and 0.185℃/10a.Annual average maximum and minimum temperatures also changed asymmetric in majority area.The maximum and minimum temperatures increased quickly in the plateau of western Sichuan,but the rising rate of minimum temperature was significantly higher than that of maximum temperature,which resulted to diurnal temperature range reducing obviously in the west of plateau.The lowest annual average maximum temperature was in 1980s and the highest was in 2000s.The lowest annual average minimum temperature was in 1960s and the highest was in 2000s.The highest diurnal temperature range was in 1960s,and the lowest was in 1980s.Annual average maximum and minimum temperatures changed abruptly in 1996 and 1993 respectively.Annual average diurnal temperature range changed abruptly in 1973 and 2005.The climate trend rate and abrupt change of average annual maximum and minimum temperatures were different,which leaded to abrupt change of the diurnal temperature change was inconsistent.