基于SPEI指数的丹寨县干旱气候特征及气象因子分析

Analysis of Drought Climate Characteristics and Meteorological Factors in Danzhai County Based on SPEI Index

摘要: 基于1960~2022年丹寨县国家气象观测站逐月气象数据，通过计算月、季、年时间尺度的标准化降水蒸散指数(SPEI)的序列变化情况，采用M-K突变检验和相关分析法分析了丹寨县月、季、年时间尺度的干旱演变特征和各类气象因子与SPEI的相关性。结果表明：1) 1960~2022年丹寨县月、季、年SPEI值均有年代际的变化，总体向湿润化方向发展。2) 春旱事件发生频率最高，秋旱次之，春、秋季节主要以轻到中旱为主，重旱高发期主要在夏季和冬季。季节变化气候特征中，秋季向干旱趋势发展，春、夏、冬三个季节为向湿润趋势发展。3) 年尺度及季尺度降水量与SPEI相关性最强，季节尺度的气象因子对SPEI的影响更明显。

Abstract: Based on monthly meteorological data from the National Meteorological Observatory of Danzhai County from 1960 to 2022, the time series changes of standardized precipitation evapotranspiration index (SPEI) at monthly, seasonal, and annual scales were calculated. The M-K mutation test and correlation analysis were used to analyze the drought evolution characteristics at monthly, seasonal, and annual time scales in Danzhai County, as well as the correlation between various meteorological factors and SPEI. The results show that: 1) From 1960 to 2022, the monthly, quarterly, and annual SPEI values in Danzhai County showed interdecadal changes, and generally developed towards humidification. 2) The frequency of spring drought events is the highest, followed by autumn drought. The spring and autumn seasons are mainly characterized by mild to moderate drought, and the high incidence period of severe drought is mainly in summer and winter. In the climate characteristics of seasonal changes, autumn tends to develop towards drought, while spring, summer, and winter tend to develop towards wetness. 3) Annual and seasonal precipitation have the strongest correlation with SPEI, with seasonal meteorological factors having a more significant impact on SPEI.