中文摘要：

基于22个气象站点逐日地面气温数据,以日最高温度（DMT）35℃以上和38℃以上的极端高温事件（EHTE）的发生频次作为研究指标,运用M-K检验、滑动t检验、小波分析,分析了甘肃省1961—2011年夏季极端高温事件的变化特征.结论如下：35℃以上极端高温事件的发生频次在1960—1963年逐渐升高,1964—1998年该值逐渐降低,1999—2011年又逐渐升高,1997年为突变年份,普遍存在3~4年的周期,1966—1977年和1992—2011年两个时间段存在一个11~12年左右的周期,1983—1991年存在一个6年左右的周期.38℃以上极端高温事件发生频次在1960—1964年呈现逐渐升高的趋势,1965—1979年逐渐降低,1980年、1981年出现短暂升高,1982—1985年又逐渐降低,1986—2011年呈现出逐渐升高的趋势,普遍存在着一个3~4年的周期,1960—1984年存在一个14~15年的周期,1993—2011年存在着一个11~12年的周期.

英文摘要：

Based on the daily temperature data at 22 meteorological stations, the occurrence frequencies of extreme high temperature event （EHTE） which daily maximum temperature （DMT） exceeding 35 ℃and 38 ℃ were computed respectively as studying targets. Employing the methods of M-K test, sliding t test, wavelet analysis,we explored the temporal variability of EHTE of Gansu province in the period 1960-2011. The results were as follows ：the occurrence frequencies of EHTE which DMT exceeding 35℃ increased from 1960 to 1963, whereas it decreased from 1964 to 1998, and it increased again from 1999 to 2011. the mutation occurred in 1997. Generally speaking, the cycle was 3 to 4 years. But in the periods of 1966-1977 and 1999-2011 ,the cycle was 12 years about, and the years from 1983 to 1991, the cycle was about 6 years. Meanwhile, the occurrence frequencies of EHTE which DMT over 38~C presented a more complex variation. It showed an increasing trend from 1960 to 1964,while a decreasing trend from 1965 to 1979,then increased in the year 1980 and 1981 ,decreased from 1982 to 1985. While from 1986 to 2011 it increased again. Most of the cycles were also 3 to 4 years ,the period of 1960-1984 had a cycle of 14 - 15 years ,and the period of 1993-2011 had a cycle of 10 - 12 years.