Yields of winter wheat, silage maize and grain maize in the main arable areas of the European Union (E.U.) were calculated with a simulation model, WOFOST, using historical weather data and average soil characteristics. The sensitivity of the model to individual weather variables was determined.Subsequent analyses were made using climate change scenarios with and without the direct effects of increased atmospheric CO 2. The impact of crop management in a changed climate was also assessed. The various climate change scenarios used appear to yield considerably different changes in yield, both for each location and for the E.U. as a whole.