Future changes in the flows of virtual water
Agricultural trading from water rich areas has been shown to help offset insufficient food production in regions of increasing water stress. The trading of the water embedded in crops, known as virtual water trade, has received increasing interest in the scientific community, however little is known about how it may change into the future. Here, using the GCAM model, we estimate future changes in the amount of renewable and nonrenewable virtual water trade. This analysis utilizes the Shared Socioeconomic Pathways – Representative Concentration Pathways framework by considering the evolution of virtual water trading in the “middle of the road”, SSP2-RCP6.0 scenario. This study provides, for the first time, a projection of all sources of virtual water trade in the future while accounting for changing socioeconomic conditions and general circulation model derived climate conditions. We provide global, regional, and basin level estimations of virtual water exports for all green and blue water and for nonrenewable groundwater, while also tracking the exported crops contributing to the necessity of virtual water trading. Regional population dynamics are found to have large implications for how virtual water trade networks may evolve towards the end of the century. We find that exports of both blue and green water are expected to increase by at least 300% by the end of the century and nonrenewable groundwater trade at least doubles. Areas of North America, the La Plata, and Nile River basins are found to contribute extensively to both renewable and nonrenewable virtual water exports, while much of Europe, Africa, and the Middle East rely heavily on the importing of all sources of virtual water by 2100.