Wat. Resour. Res. http://doi.org/kq5 (2013)

Water scarcity in the Middle East arises from the combination of climatic and water management factors. As the climate changes, water resource management is likely to become increasingly important. In river systems such as the Tigris and Euphrates River Basins, that traverse national boundaries, this can be particularly challenging because management choices in one part of the catchment frequently have implications for areas outside the decision-makers' jurisdiction. In the absence of well-established international collaboration, whole-catchment management can be challenging, not least because of the paucity of hydrological data.

To try to fill this gap in hydrological data for the north-central Middle East, Katalyn Voss, from the University of California Center for Hydrologic Modeling, USA, and co-workers used the Gravity Recovery and Climate Experiment (GRACE) satellite mission to evaluate trends in freshwater storage in the region.

The GRACE data reveal a steep decrease in total water storage of approximately 27.2±0.6 mm per year between 2003 and 2009. Additional remote-sensing and land surface modelling point to groundwater losses as the greatest contributor to this trend. This remote sensing and modelling approach may offer the best available practice for monitoring the response of water resources to climatic and management choices in data-poor regions, and enhance the possibility of science-informed collaborative water management.