PDSI-based analysis of characteristics and spatiotemporal changes of meteorological drought in china from 1982 to 2015

A monthly Palmer Drought Severity Index(PDSI)from 1982 to 2015was constructed using the monthly data from China’s surface meteorological observation to measure meteorological drought in China. The characteristics and spatiotemporal changes of meteorological drought were analyzed. The results show that there are significant spatial differences in the characteristics of meteorological drought in China with long average droughtduration and high intensityin semi-humid and semi-arid regions. Across the country as a whole, the drought frequency per unit area is 0. 44 times per year and the average drought duration is 6 months per time. The characteristics of meteorological drought have changed significantly and the frequency, duration and intensity of drought present an upward trend. The drought situation in semi-humid and semi-arid regions has gradually become severe. The meteorological drought has significant spatiotemporal changes with interannual and seasonal PDSI all showing a downward trend. The meteorological drought is generally aggravating concentrated in semi-humid and semi-arid regions such as Southeastern Qinghai, Shaanxi-Gansu-Ningxia, Shanxi, Northern Inner Mongolia and Northern Heilongjiang. In some humid regions such as Central Sichuan, Chongqing, Hubei, and Yunnan-Guizhou areas, the trend of aggravation is also significant. © 2020, Editorial Board of Water Resources Protection. All rights reserved.