Southern Hemisphere dominates recent decline in global water availability

作者：Yongqiang Zhang, Congcong Li, Francis H. S. Chiew, David Post, Xuanze Zhang, Ning Ma, Jing Tian, Dongdong Kong, L. Ruby Leung, Qiang Yu, Jiancheng Shi, Changming Liu · 发表于：Science · 年份：2023 · DOI：10.1126/science.adh0716 · 被引用次数：160 · 研究领域：Climate variability and models、Plant Water Relations and Carbon Dynamics、Hydrology and Watershed Management Studies

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 Niño-Southern Oscillation. This study highlights their dominant role in controlling global water availability.