Uncovering Key Drivers of Future Virtual Water Trade and Global Water Use
Globalization has brought increased access to agricultural trade around the world, which continues to rapidly expand. Traded goods redistribute water, virtually, around the world. Virtual water trade is an increasingly active area of research, but gaps remain in our understanding of how compounding future uncertainty may change the key drivers in agricultural virtual water trade and the water resources required to meet global demand. Here, we conduct an exploratory analysis of the impacts that varying socioeconomic futures, energy transitions, regional trade, and climatic impacts have on global and regional water resources. We utilize GCAM to capture the evolving multisector dynamics brought upon through the interconnectedness of human and Earth systems. We model a suite of 7040 exploratory futures and leverage a Classification and Regression Tree (CART) analysis to determine key drivers of water resource utilization and virtual water trade. Here, we find that socioeconomic deviations across scenarios act as the largest driver of change in water utilization and trade by the end of the century. However, when we look within individual socioeconomic change scenarios, we find that water utilization and trade in dry regions is consistently driven by climatic change induced water supply variability, regardless of underlying socioeconomic assumptions. Further, in these scenarios we find that basins in the mid-latitude regions display differing drivers of change across socioeconomic scenarios. This represents the most comprehensive investigation of future virtual water trade and water utilization drivers to date and provides an understanding of how regional teleconnections and future socioenvironmental change may shape local water requirements for meeting future global agricultural demands.