安徽省重大旱灾对称性特征及其趋势判断

基于安徽省14个气象站点1961~2013年逐月降水数据,采用克里金空间插值法、经验正交函数分解法(EOF)和降水距平百分率对安徽省降水的时空变化特征进行分析,并对安徽省旱灾的发生趋势进行判断。结果表明:(1)近53年安徽省年降水量呈上升趋势,但目前处于下降趋势;(2)在空间上降水量自南向北逐渐减小,根据EOF分析,安徽省降水的空间分布表现为长江流域与淮河流域之间降水反向变化的特征,淮河以北地区与其余地区降水反向变化的特征,皖西大别山区和安徽北部降水偏多,其余地区降水偏少的特征;(3)安徽省的重大干旱符合可公度特征并存在时间对称性规律,计算得出2016年左右安徽省可能发生严重干旱,随机概率为61.1%。该研究对安徽省未来农业及经济的稳健发展具有重要意义。

Symmetry Characteristics and Trend Judgment of Drought in Anhui Province, China

Based on meteorological data from 14 stations in Anhui Province, China during 1961 to 2013, using the Kringing spatial interpolation method, Mann-kendall mutation test, empirical orthogonal function and precipitation anomaly percentage, patial and temporal characteristics of precipitation were studied and trend of drought in Anhui Province was predicted. Results show that (1) during the past 53 years, average annual precipitation of Anhui Province has increased, but with a process of decline recently; (2) precipitation decreases gradually from south to north. Spatial distribution of the first mode shows reverse trend between the Yangtze River and Huaihe River. Besides, spatial distribution of the second mode shows that the north of the Huahe River is low while the other region is high. The third mode shows that the precipitation in the Northern Anhui Province rises while the other region decrease; and (3) severe drought in Anhui Province complys with commensurability and time symmetry, and there exist possibilities of great disasters in 2015 and around 2016, with probabilities being respectively 55.56% and 61.1%. The study is of great significance to the agricultural and economic development in Anhui Province.