广东省干旱灾害空间分布特征

Spatial characteristics of drought hazard in Guangdong Province

利用1956 2005年126个雨量站逐月降水资料,采用标准化降雨指数和经验正交函数分解法,探讨了广东省干旱灾害空间分布规律.结果表明:广东省虽然总体比较湿润,但局部干旱时有发生,且在空间上存在东西差异、南北差异、中部差异的特点;春旱大致呈自西向东、自北向南逐渐加重的趋势;秋旱空间分布特点与春旱相反,由东向西、由南向北逐渐加重;春旱、秋旱在中部地区也有微弱的差异.

Based on the monthly precipitation data from 126 precipitation stations during the period of 1956- 2005 in Guangdong Province, the spatial characteristics of drought events defined by standardized precipitation index technique were studied using the Empirical Orthogonal Function method. The results indicate that drought episodes occurred in specific regions though the Guang- dong Province is relatively humid as a whole. Besides, evident regional differences can be found in the occurrences of drought e- vents. Specifically, drought severity in spring is usually enhancing from the west to the east and from the north to the south parts of Guangdong Province; spatial distribution of occurrences of drought events in autumn however shows adverse patterns when com- pared to that in spring, i.e. the drought events in autumn are intensifying from the east to the west and from the south to the north parts of the Guangdong Province. Furthermore, slight uneven spatial distribution of drought events can also be identified in the middle parts of the Guangdong Province. The results of this study may be of practical and scientific merits in terms of effective wa- ter resources management and also for scientific management of agricultural activities across the Guangdong Province.