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Abstract Alarming projections of climate change, decline in crop yields, and increased food demand constitute daunting threats to African food production and sustainable water management. Here, we map this complex water-food nexus by combining gridded climate data and process-based crop modelling to quantify scenarios of crop water footprint under Representative Concentration Pathway 2.6 and Representative Concentration Pathway 6.0 for time horizons 2040, 2070 and 2100. We show that high-input agricultural management coupled with the expansion of irrigation infrastructure could generate an average reduction of water use intensity up to 64% for staple crops, but only 5% for cash crops, by 2040. Notwithstanding the positive effect of intensification, between 82 Km3 (2040) and 102 Km3 (2100) of additional blue water will be required to sustain the increased yields. Our scenarios are suited for identifying locations where crops are subject to high climate impacts and where crop production shows trade-offs between high-input management and irrigation demand.

Virtual water flows embodied in the international food trade by the largest companies can exceed those of entire nations highlighting the importance of corporations for water stewardship and security, suggests an analysis of the top 9 transnational corporations exporting Brazilian soy.