Virtual water flows in a real world

Virtual water was introduced by John Anthony Allan in 1998 as a measure of the amount of water required for the production of goods and services. Following the initiation of the Sustainable Development Goals in recent years, an intensified focus on environmental sustainability, particularly regarding water sustainability, has emerged. In this context, virtual water, as a crucial tool for water resources management, garnering attention from the academic community. Existing studies on virtual water have made significant contributions on quantifying the virtual water content embedded in commodities, delineating cross-regional patterns of virtual water flows, unveiling the temporal evolution and spatial distribution patterns of virtual water trade, assessing the economic valuation of virtual water through shadow pricing techniques, and analyzing the drivers influencing virtual water flows. However, there are still research gaps in the current literature on virtual water trade forecasting, virtual water accounting in different sectors (such as services and light industry), grey water footprint estimation and water scarcity indices. Moreover, virtual water research involves hydrology, economics and ecology. Multidisciplinary crossover will be an important trend in virtual water research in the future. This article seeks to comprehensively review current dialogues and investigations regarding virtual water and virtual water trade, assessing their impacts on a range of natural, social, and economic dimensions, and help scientists advance the frontiers of the field, as well as help policymakers adapt regional trade patterns and manage water resources more efficiently.