Forests support global crop supply through atmospheric moisture transport

Abstract Anomalous precipitation patterns associated with climate change increasingly threaten global crop supply. Forests, as major moisture source, could potentially buffer these risks, yet their specific role in sustaining agriculture and global crop supply remains underexplored. We investigate global forests’ contribution to crop production and export by estimating moisture flows from forests to agricultural areas and pairing them with traded crop flows. We find that agricultural areas in 155 countries rely on transboundary forests for up to 40% of annual precipitation, whereas in 105 countries, as much as 18% of precipitation is recycled from forests nationally. Moisture from forests globally supports 18% of crop production and 30% of crop export studied. We show that crop producers, exporters and importers are directly and indirectly dependent on upwind forested countries through three typologies. Our study implies that strategically conserving forests located upwind of agricultural areas could be leveraged to safeguard global crop supply.