Are droughts becoming more frequent or severe in China?

Drought in China is a recurring phenomenon that becomes one of the most damaging climate-related hazards to impact natural habitats, ecosystems, and many economic and social sectors. Thus, it is of critical significance to investigate the variation patterns of droughts over China with long-term data time series. In recent years, meteorologists have developed a number of indices and methods to characterize droughts for particular regions, and Standardized Precipitation Index (SPI) was employed in this study. To consider the spatial variability of underlying conditions, the study area was divided into grids with a size of two square degrees, and then the inverse distance-squared weighted method was used to spatially interpolate precipitation for every grid. Monthly precipitation data of more than 700 stations was used to explore the drought in China during 1951-2010. We investigated the spatio-temporal variations of SPI, drought duration, extreme drought frequency, percentage area of drought in the entire China. The results showed different drought variation information in different regions within China for the past 60 years. It suggested that the regional drought monitoring should be strengthened particularly in the percentage areas of severe drought. In addition, the results may also be potentially helpful to establish the drought early warning system in China.