基于云模型的安徽省干旱时空分布特征分析

Analysis of Characteristics of Temporal-spatial Drought Distribution in Anhui Province Based on Cloud Model

为分析安徽省干旱时空分布特征,依据安徽省14个典型站点1962~2013年逐日降水量资料,以降水量距平百分率作为干旱等级评价指标,引入云模型研究了安徽省干旱时空分布的均匀性和稳定性特征,并采用ArcGIS的反距离权重法分析了不同时间尺度下的干旱频率空间分布特征。结果表明,安徽省干旱年际变化呈逐年波动式的缓解趋势;在时间尺度上,干旱年际分布均匀性最好,春季最不均匀,夏季稳定性最好,年际和春季次之,秋、冬季最差;在空间尺度上,皖北地区干旱分布最不均匀,皖南地区的均匀性最好,皖北地区稳定性最好,皖南地区稳定性最差;安徽省干旱频率空间分布基本呈纬向分布,即干旱发生频率自北向南递减。

Based on the daily rainfall data of the 14 typical rainfall sites from 1962 to 2013 in Anhui Province, precipitation anomaly percentage was used to analyze the characteristics of the spatial and temporal distribution of drought. Then the cloud model was introduced to analyze the characteristics of the spatial and temporal distribution of drought, and the indices of homogeneity and stability were used for reflecting characteristics of temporal spatial distribution of drought. The characteristics of the spatial distribution of drought at annual and seasonal time scale were analyzed with ArcGIS software by the inverse distance weighting method. The results show that the annual variation of drought has a fluctuation and decreasing tendency in Anhui Province. The homogeneity of the annual drought is the best and spring is the worst. The stability of drought in summer is the best, followed by annual and spring drought, and the worst is autumn and winter. Seeing the difference characteristics in the space using the homogeneity, we find that the drought of Wanbei area is the worst and Wannan area is the best. But the stability of drought in Wanbei area is the best and Wannan area is the worst. Generally, the frequency of drought in Anhui Province descends from north to south.