Methods: Using the dynamic global vegetation and water balance model LPJmL, we quantified the VWC of temperate cereals and maize, at high spatial resolution (0.5°). We analyzed present conditions and scenarios of future climate and increasing atmospheric CO 2 concentrations (HadCM3, ECHAM5 and CCSM3 climate models, A2 emissions scenario). Rainfed temperate cereals 1999-2003 Current VWC: Lowest values were found e.g. for Central Europe, and highest values are common in large parts of Africa, indicating that water-use efficiency of crops is much lower in the latter region. The regional patterns of VWC result from complex and interactive processes; the dominant factor is the crop yield level (high VWC values occur most frequently in regions with low yields).