Spatio-temporal variation of drought in China during 1961–2012: A climatic perspective
Spatio-temporal variation of drought in China during 1961–2012: A climatic perspective
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DOI：
10.1016/j.jhydrol.2014.09.047
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发表时间：
2015-07
影响因子：
6.4
通讯作者：
Kai Xu;Dawen Yang;Hanbo Yang;Zhe Li;Yue Qin;Yan Shen
中科院分区：
文献类型：
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作者：
Kai Xu;Dawen Yang;Hanbo Yang;Zhe Li;Yue Qin;Yan Shen
了解干旱的时空变化对干旱评估至关重要。在以往的研究中，干旱事件通常是在空间和时间上分开识别的，忽略了动态过程的本质。为了更好地了解近半个世纪以来中国干旱的变化情况，从气候角度出发，利用多种干旱指数对中国干旱的时空变化进行了综合分析。基于SPI 3（3个月标准化降水指数）、RDI 3（3个月侦察干旱指数）和SPEI 3（3个月标准化降水蒸散指数）的0.25°网格化指标，建立了1961 - 2012年中国干旱事件的三维聚类方法。干旱事件进一步通过五个参数来表征：持续时间、受影响面积、严重程度、强度和重心。利用遥感土壤水分数据验证了干旱事件识别的合理性。结果表明：1962-1963年和2010-2011年发生的两次世纪以来最严重的干旱事件席卷了中国一半以上的非干旱地区。华北平原至长江下游地区是我国大范围干旱的集中地区。华北平原西部、黄土高原、四川盆地和云贵高原等地区有明显的干旱化趋势，这主要是由于降水量的显著减少造成的。三种干旱指数在湿润地区的表现基本一致，而SPI和RDI在干旱地区的表现要优于SPEI。
Understanding the spatial and temporal variation of drought is essentially important in drought assessment. In most previous studies, drought event is usually identified in space and time separately, ignoring the nature of the dynamic processes. In order to better understand how drought changes have taken place in China during the past half-century, we carried out a comprehensive analysis of their spatio-temporal variation based on multiple drought indices from a climatic perspective. A 3-dimensional clustering method is developed to identify drought events in China from 1961 to 2012 based on the 0.25° gridded indices of SPI3 (3 months Standardized Precipitation Index), RDI3 (3 months Reconnaissance Drought Index) and SPEI3 (3 months Standardized Precipitation Evapotranspiration Index). Drought events are further characterized by five parameters: duration, affected area, severity, intensity, and centroid. Remotely sensed soil moisture data were used to validate the rationality of identified drought events. The results show that the two most severe drought events in the past half century which occurred in the periods 1962–1963 and 2010–2011 swept more than half of the non-arid regions in China. Large magnitude droughts were usually centered in the region from North China Plain to the downstream of Yangtze River. The western part of North China Plain, Loess Plateau, Sichuan Basin and Yunnan-Guizhou Plateau had a significant drying trend, which is mainly caused by the significant decrease of precipitation. The three drought indices have almost the same performance in the humid regions, while SPI and RDI were found to be more appropriate than SPEI in the arid regions.