A Spatially Explicit Assessment of Growing Water Stress in China From the Past to the Future. Issue 9 (2nd September 2019)

• Record Type: Journal Article
• Authors: Liu, Xingcai; Tang, Qiuhong; Liu, Wenfeng; Veldkamp, Ted I.E.; Boulange, Julien; Liu, Junguo; Wada, Yoshihide; Huang, Zhongwei; Yang, Hong
• Is Part Of: Earth's future. Volume 7:Issue 9(2019)
• Page Start: 1027
• Page End: 1043
• Publication Date: 2019-09-02
• Subjects: water stress -- water scarcity -- water withdrawal -- streamflow -- climate change -- socioeconomic development; Environmental sciences -- Periodicals; Environmental sciences; Periodicals; 550
• DOI: 10.1029/2019EF001181
• Languages: English
• ISSNs: 2328-4277

Abstract

Abstract: In this study, we examine the spatial and temporal characteristics of water stress in China for the historical (1971–2010) and the future (2021–2050) periods using a multimodel simulation approach. Three water stress indices (WSIs), that is, the ratios of water withdrawals to locally generated runoff (WSIR ), to natural streamflow (WSIQ ), and to natural streamflow minus upstream consumptive water withdrawals (WSIC ), are used for the assessment. At the basin level, WSIR estimates generally match the reported data and indicate severe water stress in most northern basins. At the grid cell level, the WSIs show distinct spatial patterns of water stress wherein WSIR (WSIQ ) estimates higher (lower) water stress compared to WSIC . Based on the WSIC estimates, 368 million people (nearly one third of the total population) are affected by severe water stress annually during the historical period, while WSIR and WSIQ suggest 595 and 340 million, respectively. Future projections of WSIC indicate that more than 600 million people (43% of the total) might be affected by severe water stress, and half of China's land area would be exposed to stress. The found aggravating water stress conditions could be partly attributed to the elevated future water withdrawals. This study emphasizes the necessity of considering explicit upstream and downstream relations with respect to both water availability and water use in water stress assessment and calls for more attention to increasing levels of water stress in China in the coming decades. Plain Language Summary: Severe water stress in China has been widely reported, but its time evolution and spatial patterns are rarely assessed. We examine the spatial and temporal change patterns of water stress in China by using multimodel simulations and three different water stress indices (WSIs). Results suggest that different WSIs imply distinct spatial patterns of water stress over China. The WSIs indicate that water stress conditions in northern China are quite distinct from that in southern China. During the past decades (1971–2010), severe water stress is found in northern areas while little is found in southern areas. In the future (2021–2050), however, water‐stressed areas might expand in southern China and water stress levels might aggravate in urban areas, putting considerably more people exposed to severe water stress. This assessment provides useful information for regional water planning/management within the context of future climate change and socioeconomic development in China. Key Points: Water stress estimates can be much different with the consideration of upstream water withdrawal and consumption Severe water stress conditions are found in northern China in the past Water‐stressed areas significantly expand over southern China in the future