Based on the observation data of temperature in Chengxian meteorological station( the climate representative station of Longnan City,Gansu Province) during 1961-2014,the annual,seasonal and monthly changes of temperature were analyzed,and the abrupt changes in relevant variables were tested using the cumulative anomaly method. The results showed that annual average temperature in Chengxian County increased by 0. 138 ℃/10 a in the past 54 years. There was an obvious sudden change in annual average temperature around 1996. The annual average temperature showed a downward trend before 1996 and an upward trend after 1996. Average temperature in spring,summer,autumn and winter increased by 0. 113,0. 028,0. 157 and 0. 259 ℃/10 a respectively. The fluctuation of average temperature in spring and winter was the largest,followed by summer,while the fluctuation was the smallest in autumn. There were certain differences between various seasons in terms of the years with sudden changes in average temperature,which was not consistent with the years with the sudden changes in annual average temperature. The changing rate of monthly average temperature was the largest in February( up to 0. 412 ℃/10 a),followed by March,April and November,but it was the smallest in May( only 0. 005 ℃/10 a). The maximum of monthly average temperature appeared mostly in the 21 stcentury,while the minimum appeared in the 20 thcentury.
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