Revealing the potential geographic convergence of global water scarcity risk and virtual water trade inequality: A three-module integrated analytical approach

Abstract

Unequal virtual water transfer may aggravate local water scarcity risk. However, the quantitative confirmation of a clear geographic convergence between virtual water transfer and water scarcity risk remains undetermined. We present an analytical framework that reveals the spatial matching between global water scarcity risk and virtual water trade inequality. This framework integrates a three-dimensional water scarcity risk assessment, hybrid input-output analysis, pollution trade term construction, and geographic convergence identification. The framework is applied to 123 countries for long-term validation from 1991 to 2021. We show that despite global improvements in water efficiency and security, countries exceeding the maximum water vulnerability threshold have increased by 50 %. South Asia is the largest net exporter of virtual water. Central Asia exhibits the most pronounced virtual water trade inequality. To achieve the same economic growth, Central Asia needs to pay several times the local water consumption costs of developed regions (15.9 − 83.6 times, 2021). In the past 30 years, the average geographic convergence index exceeded 0.8. Countries facing severe water scarcity also exhibit pronounced inequalities in virtual water trade, indicating that a significant geographic convergence relationship exists. Effectively responding to this unsustainable relationship necessitates balancing both domestic resource risk management and global virtual water trade regulation.

Keywords

Water scarcity risk / Virtual water transfer / Global inequity / Geographic convergence / Water resources management

CRediT authorship contribution statement

Qiting Zuo: Writing - review & editing, Writing - original draft, Supervision, Resources, Project administration, Funding acquisition, Formal analysis, Conceptualization. Zhizhuo Zhang: Writing - original draft, Visualization, Software, Methodology, Data curation. Junxia Ma: Writing - review & editing, Supervision, Investigation. Qingsong Wu: Writing - review & editing, Validation, Data curation. Yihu Ji: Writing - review & editing, Validation.

Declaration of competing interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

This work was supported by National Natural Science Foundation of China (Grant No. 52279027), National Key R&D Program of China (Grant No. 2021YFC3200201), Key Research Project on Decision Consultation of the Strategic Development Department of China Association for Science and Technology (Grant No. 2023070615CG111504), and China Engineering Science and Technology Development Strategy Henan Research Institute Strategic Consulting Research Project (Grant No. 2024HENYB01).

Supplementary materials

Supplementary material associated with this article can be found, in the online version, at doi:10.1016/j.geosus.2025.100399.

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