Groundwater depletion embedded in international food trade ($)

Many food-producing regions rely on the withdrawal of water from non-renewable underground sources, a condition called groundwater depletion for irrigation (GWD). Globally, GWD increased by 22% between 2000 and 2010. When food produced with GWD is exported, the exporting country is essentially exporting its non-renewable water resources. Dalin et al. analyzed regional and crop-specific GWD data to identify areas of concern. Major “water” exporters are the US (particularly California), Pakistan, and India, with China a major importer. The five crops that contribute most to GWD are wheat, rice, sugar crops, cotton and maize. Nature 10.1038/nature21403