Drought evolution, severity and trends in mainland China over 1961-2013

Ning Yao; Yi Li; Tianjie Lei; Lingling Peng

doi:10.1016/j.scitotenv.2017.10.327

Drought evolution, severity and trends in mainland China over 1961-2013

Sci Total Environ. 2018 Mar:616-617:73-89. doi: 10.1016/j.scitotenv.2017.10.327. Epub 2017 Nov 16.

Authors

Ning Yao¹, Yi Li², Tianjie Lei³, Lingling Peng¹

Affiliations

¹ College of Water Resources and Architectural Engineering, Northwest Agriculture and Forestry University, Yangling, Shaanxi 712100, China; Institute of Water Saving Agriculture in Arid Areas of China, Northwest Agriculture and Forestry University, Yangling, Shaanxi 712100, China.
² College of Water Resources and Architectural Engineering, Northwest Agriculture and Forestry University, Yangling, Shaanxi 712100, China; Institute of Water Saving Agriculture in Arid Areas of China, Northwest Agriculture and Forestry University, Yangling, Shaanxi 712100, China. Electronic address: liyi@nwsuaf.edu.cn.
³ China Institute of Water Resources and Hydropower Research (IWHR), Beijing 100038, China.. Electronic address: leitj@iwhr.com.

PMID: 29107781
DOI: 10.1016/j.scitotenv.2017.10.327

Abstract

Droughts have destructive impacts on crop yields and water supplies, and researching droughts is vital for societal stability and human life. This work aimed to assess the spatiotemporal evolution of droughts in mainland China over 1961-2013 using four drought indices. These indices were the percentage of precipitation anomaly (Pa), standard precipitation index (SPI), standard precipitation evapotranspiration index (SPEI) and evaporative demand drought index (EDDI) at multiple timescales ranging from 1-week to 24-month. The variations of the SPI, SPEI and EDDI were compared with historical severe or extreme droughts. The general increases of the Pa, SPI and SPEI, and general decrease of the EDDI, consistently implied an overall relief of drought conditions over 1961-2013. The different drought indices revealed historical drought conditions, including the national extreme droughts in 1961, 1965, 1972, 1978, 1986, 1988, 1992, 1994, 1997, 1999 and 2000, but various drought severity levels were classified for each drought event since the classification standards differed. Although the SPI and SPEI performed better than the EDDI and there were higher correlations between the SPI and the SPEI, all the indices were regional- or station-specific and have identified historical severe or extreme drought events. At shorter timescales, the EDDI revealed earlier onsets and ends of flash droughts, unlike those indicated by the SPI and SPEI. The comparison of the different indices based on the historical drought events confirmed the uses of the Pa, SPI and SPEI for determining continuous droughts and that of the EDDI for identifying flash droughts.

Keywords: Drought index; Historical extreme drought event; Timescale; Trend test.