Arid Zone Research ›› 2024, Vol. 41 ›› Issue (5): 717-729.doi: 10.13866/j.azr.2024.05.01

• Weather and Climate • Previous Articles     Next Articles

Spatial and temporal variation of drought in Northwest China based on CMIP6 model

SHAN Jian'an1(), ZHU Rui1, YIN Zhenliang2,3(), YANG Huaqing1, ZHANG Wei1, FANG Chunshuang1   

  1. 1. National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring, Key Laboratory of Science and Technology in Surveying & Mapping, Gansu Province, Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730000, Gansu, China
    2. Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, National Cryosphere Desert Data Center, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China
    3. College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266000, Shandong, China
  • Received:2023-11-18 Revised:2024-01-21 Online:2024-05-15 Published:2024-05-29

Abstract:

Based on data from 152 meteorological stations in Northwest China and 16 climate models of CMIP6, the CMIP6 model data were bias-corrected using the RoMBC method. The Standardized Precipitation Evapotranspiration Index (SPEI) was then constructed to analyze the spatial and temporal distribution and variation of drought in Northwest China under the historical and future scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP5-8.5). The results are as follows: (1) Under the historical scenario, the northwest area experienced a notable increase in both the temperature and precipitation. The temperature and precipitation have been rising at a rate of 0.15-0.74 ℃ and 2.71-14.83 mm per decade, respectively, and the same is expected for future scenarios. (2) From 1975 to 2014, the annual and seasonal SPEI in Northwest China decreased overall. The maximum decline rate in spring was 0.19 per decade. Droughts in most areas were increasingly intense throughout the year, particularly in spring and winter. In terms of drought frequency in Northwest China, mild and moderate droughts appeared more than severe and extreme droughts, and this type of natural disaster was more frequent in the east of the country than in the west. (3) From 2020 to 2100, Northwest China is likely to suffer from droughts, but there are no distinct drought characteristics identified in the research under the SSP1-2.6 scenario. The northwest region is expected to experience an increase in the number of droughts, trends in drought, and drought frequency under the other three scenarios. The most severe drought conditions were observed under the SSP5-8.5 scenario. This study provides insights into the spatial and temporal development of drought in Northwest China using meteorological and model data. The findings can serve as a basis for drought risk assessment, scientific water resources management, and agricultural production in the region.

Key words: SPEI, spatial-temporal pattern of drought, CMIP6, Northwest China