Southern Hemisphere dominates recent decline in global water availability

• 成果类型: Article
• 署名作者: Zhang, Yongqiang; Li, Congcong; Chiew, Francis H. S.; Post, David A.; Zhang, Xuanze; Ma, Ning; Tian, Jing; Kong, Dongdong; Leung, L. Ruby; Yu, Qiang; Shi, Jiancheng; Liu, Changming
• 署名单位: Chinese Academy of Sciences; Institute of Geographic Sciences & Natural Resources Research, CAS; Chinese Academy of Sciences; Institute of Soil & Water Conservation (ISWC), CAS; Northwest A&F University - China; Commonwealth Scientific & Industrial Research Organisation (CSIRO); CSIRO Environment; China University of Geosciences; United States Department of Energy (DOE); Pacific Northwest National Laboratory; Chinese Academy of Sciences; National Space Science Center, CAS
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-11477
• DOI: 10.1126/science.adh0716
• 发表日期: 2023-11-03
• 页码: 579-584
• 关键词: surface-water; evapotranspiration; TRENDS; variability; groundwater; regression; streamflow; WORLD

摘要

Global land water underpins livelihoods, socioeconomic development, and ecosystems. It remains unclear how water availability has changed in recent decades. Using an ensemble of observations, we quantified global land water availability over the past two decades. We show that the Southern Hemisphere has dominated the declining trend in global water availability from 2001 to 2020. The significant decrease occurs mainly in South America, southwestern Africa, and northwestern Australia. In the Northern Hemisphere, the complex regional increasing and decreasing trends cancel each other, resulting in a negligible hemispheric trend. The variability and trend in water availability in the Southern Hemisphere are largely driven by precipitation associated with climate modes, particularly the El Nino-Southern Oscillation. This study highlights their dominant role in controlling global water availability.