基于Z指数的寿阳县干旱气候特征分析

利用寿阳县1961—2018年逐月降水资料，采用降水Z指数作为气象干旱等级指标，分析该地区的干旱变化特征。结果表明：近58年来，寿阳县年气候呈干旱化趋势，出现干旱16年，发生频率为27.6％，1997－2010年期间干旱发生频率最高，干旱程度最为严重；季节干旱中，春季有湿润化趋势可能，夏、秋、冬季呈不明显干旱化趋势；四季干旱发生频率，春季32.8％、夏季27.6％、秋季37.9％、冬季31.0％。春季干旱主要发生在1971－1982年期间，夏季干旱在1965－1974年、1980－1986年、1997－2001年期间旱情最严重，秋季干旱在1994－2010年和冬季干旱在1981－2002年为多发阶段。季节干旱，除冬季外，其它三季干旱都对当地农作物正常生长带来极为不利的影响。

Analysis of Drought Climate Characteristics in Shouyang County Based on Z Index

Using the monthly precipitation data from 1961 to 2018 in Shouyang County and using the Z index of precipitation as an index of meteorological drought grades, the characteristics of drought changes in the area were analyzed. The results showed, in the past 58 years, the annual climate of Shouyang County has shown a trend of drought, with 16 years of drought, with a frequency of 27.6%, and the highest frequency of droughts and the most severe drought during the period of 1997-2010. In seasonal droughts, there was a tendency for humidification in spring, and there is no obvious drought trend in summer, autumn and winter. The frequency of drought in the four seasons is 32.8% in spring, 27.6% in summer, 37.9% in autumn, and 31.0% in winter. Spring drought mainly occurred during 1971-1982. Summer drought was most severe during 1965-1974, 1980-1986, and 1997-2001. Autumn drought was more frequent in 1994-2010 and winter drought in 1981-2002. Seasonal drought, with the exception of winter, the other three seasons of drought have extremely adverse effects on the normal growth of local crops.