基于SPEI的晋城地区干旱气候分析

Drought Analysis Based on SPEI in Jincheng

摘要: 利用1967~2016年晋城地区5个气象观测站的月、季、年降水资料和气温资料，计算了月尺度、季尺度和年尺度的SPEI值，并利用小波分析法对干旱发生的周期进行分析，结果表明：晋城地区全市干旱发生的频率高达56%，各站的平均干旱频率为32%；干旱多发生在春季和夏季，最易出现干旱的时间为每年的春末夏初，干旱以阶段性干旱为主，最长干旱持续时间为6个月；从干旱的发生情况来看，进入21世纪之后，干旱的发生情况要明显增多。干旱发生存在两个明显特征时间尺度：2~4 a和8~12 a，其中以8~12 a尺度周期变化表现最明显。

Abstract: Based on the monthly, seasonal, and annual precipitation data and temperature data of five meteorological stations in the Jincheng area from 1967 to 2016, the SPEI values at monthly, seasonal and annual scales were calculated, and the drought occurrence cycle was analyzed by wavelet analysis. The results show that the frequency of drought in Jincheng was up to 56%, and the average frequency of drought in all stations was 32%. The drought mainly occurred in spring and summer, and the most frequent drought occurred in late spring and early summer each year. The drought mainly occurred in stages, and the longest drought duration was 6 months. From the perspective of the occurrence of drought, the occurrence of drought will increase significantly after entering the 21st century. There are two characteristic time scales of drought occurrence: 2~4 a and 8~12 a, in which the periodic change of 8~12 a scale is the most obvious.