Acta Geographica Sinica ›› 2020, Vol. 75 ›› Issue (7): 1465-1482.doi: 10.11821/dlxb202007010

• Climate Change and Surface Process • Previous Articles     Next Articles

A multi-scalar drought index for global warming: The non-stationary standardized precipitation evaporation index (NSPEI) and spatio-temporal patterns of future drought in China

WEN Qingzhi1,2(), SUN Peng1,2,3(), ZHANG Qiang2,4, YAO Rui5   

  1. 1. School of Geography and Tourism, Anhui Normal University, Wuhu 241000, Anhui, China
    2. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal University, Beijing 100875, China
    3. State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China
    4. Academy of Disaster Reduction and Emergency Management, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
    5. Key Laboratory of Virtual Geographic Environment for the Ministry of Education, Nanjing Normal University, Nanjing 210023, China
  • Received:2019-09-18 Revised:2020-04-15 Online:2020-07-25 Published:2020-09-25
  • Contact: SUN Peng E-mail:wenzhi@163.com;sun68peng@163.com
  • Supported by:
    The Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0906);China National Key R&D Program(2019YFA0606900);National Natural Science Foundation of China(41601023);National Natural Science Foundation of China(41771536);Natural Science Foundation of Anhui Province(1808085QD117)

Abstract:

Drought is one of the most severe natural disasters that have widespread impacts on eco-environment and agriculture. Great efforts have been made on the study of the non-stationarity of hydrometeorological processes, while few reports are available addressing non-stationarity in drought index. Therefore, in this study, we attempted to develop a non-stationary standardized precipitation evaporation index (NSPEI) based on standardized precipitation evaporation index and non-stationary theory with the aim of investigating drought conditions across China in both space and time under different emission scenarios from 2006 to 2100. The results indicated that: (1) Stations with non-stationary hydrometeorological processes are concentrated in northeast China, the Huang-Huai-Hai Plain, the Yangtze River Delta, the Tibetan Plateau, the Hengduan Mountains, and the southern Xinjiang. The NSPEI has the best fitting performance at 88% of the meteorological stations considered in this study. (2) Compared with other drought indices, SPEI tends to overestimate the intensity and duration of droughts during evaluations of the future drought changes; while NSPEI avoids the weakness of SPEI in overestimation of drought intensity. Therefore, NSPEI can better monitor the meteorological droughts in China and describe the future drought changes across the country. (3) Drought monitoring results based on NSPEI indicated an increasing drought trend in northern China, and southern China is dominated by a wetting trend under the scenario of low and high emissions. Extreme dry and wet duration and occurrence frequency showed an increasing trend in China in the future under medium and high emission scenarios.

Key words: non-stationary standardized precipitation evapotranspiration index, drought monitoring, spatio-temporal patterns, global warming