利用衡阳市祁东县气象站1960~2013年逐日平均气温、降水观测数据，计算综合气象干旱指数。以国家标准«气象干旱等级GB/T20481~2006»为依据划分不同干旱等级、计算干旱日数、干旱强度等，在此基础上统计干旱日的年、年代际统计并作了线性分析，并为应对干旱提出了自己的建议：祁东县干旱日每年均有出现，但不同强度干旱日发生频率不同，在全球变暖大背景下，干旱日等级越高，其增幅愈明显；祁东县的平均干旱过程数为2.5次/a，一年出现2次干旱过程几率最大，无旱过程的几率为9.3％；在统计年干旱强度时，选用持续时间最长的一次有较好代表性。近54a来，干旱强度年变化可分为三高两低，目前处于干旱强度较高期；祁东县大部分年份有季节性干旱，单季旱以秋旱为主，在双季干旱中，夏秋连旱居多，历史上夏秋冬连旱出现了三次；为了应对日趋严重的干旱，需增强人们的防旱抗灾意识、加大水利设置投入、推广节水农业和提高干旱监测预警能力。%By using the daily average temperature data and precipitation data from 1960 to 2013 from the Weather Station of Qidong County of Hengyang City, the paper calculated the integrated meteorological drought index. The paper divided the different drought ratings, calculated the number of drought days and drought intensity in accordance with the national standards of the Meteorological Drought Rating GB/T20481~2006, and then proposed suggestions about the drought countermeasures by using the annual, decadal and linear analysis. The results show that drought has occurred in Qidong County every year, but the occurrence of different drought intensity has different probabilities. Under the background of global warming, the higher the drought day level is, the more obvious its growth is. The number of drought of Qidong County is 2. 5 each year on average. Two droughts each year is most possible. And no drought probability is 9. 3%. When counting drought intensity, the selection of the longest time has a better representative. In recent 54 years, the annual change of the drought intensity can be divided into the condition of three highs and two lows. And now we are at a higher time. The seasonal drought in Qidong County occurs in most years. The single-season drought is mainly autumn drought, while the double-season drought is summer and autumn drought in majority. In the history of Qidong County, drought took place three times from summer to winter. To deal with the increasing heavy drought, countermeasures should be taken as follows: strengthening the awareness of resisting drought; spending more money on waterpower equipment; popularizing water saving agriculture and improving the ability to monitor and predict drought.
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