近60 a来淮河流域干旱变化特征

[目的]研究淮河流域近60年来干旱的变化特征,为以后防旱抗灾提供一定的参考。[方法]利用WAP(weight average of precipitation)指数法、空间Kriging法、小波分析等方法对淮河流域干旱变化时空特征进行分析。[结果]春季WAP指数在21世纪初下降幅度较大,易发生春旱,冬季WAP指数在1980年以后明显增加,冬旱有所减轻;年均WAP指数表征的干旱存在2~3a的主周期和6~7a的次主周期;在空间上,WAP指数大致由东南向西北递减,干旱程度由东南向西北逐渐增大。[结论]WAP指数能够很好地表征淮河流域干旱发生的时间和空间特征。

Drought Variations of Huaihe River Basin in Recent 60 Years

[Objective] To analyze the drought variation characteristics of the Huaihe River basin in recent 60 years, and provide a reference for the later drought-resisting disaster. [Methods] The weight average of precipitation(WAP) index, space Kriging method, and wavelet analysis methods were used to study the drought variation of the Huaihe River basin. [Results] The spring WAP index declined greatly in the early 21st century, it is prone to drought in spring. Meanwhile the winter WAP index increased significantly after 1980 and the winter drought has reduced, and the average index of WAP representation the main cycle of drought was 2~3 years and secondary was 6~7 years. Furthermore, the WAP index of Huaihe river basin showed a progressive decrease from the southeast to the northwest while the degree of drought increases from the southeast to the northwest as a whole in space. [Conclusion] The WAP index can represent time and space characteristics of drought in the Huaihe River basin.