CR 07:225-241 (1996)  -  DOI: https://doi.org/10.3354/cr007225

Spatially explicit crop models were developed from mechanistic principles to investigate the regional impacts of climate change. The approach highlights the spatial variability of crop responses to altered environmental conditions. The mechanistic nature of the models allows some confidence to be placed in the results that are produced under climate change scenarios. Two crop models have been constructed and applied across a large European region: EuroWheat (winter wheat) and EuroSunfl (sunflower). Model results were compared with observed phenology and yield across a variety of scales and found to capture the current spatial variability in wheat and sunflower productivity. Climate change scenarios from both equilibrium and transient general circulation model experiments were applied to each crop model. Wheat yields are predicted to increase throughout Europe for all climate change scenarios. Conversely, water-limited sunflower yields decrease in most regions and scenarios. More positive effects are predicted for winter wheat than sunflower due to a lower sensitivity to increased temperature and a higher sensitivity to elevated concentrations of CO₂. The lowest yield increases for wheat and the largest yield decreases for sunflower are found in western Europe, whilst the most positive responses for both crops occur in central and eastern Europe. Predictions for southern Europe are highly sensitive both within the region and between the scenarios. The old generation of equilibrium climate change scenarios gives the worst predictions (lowest yield increases or highest yield decreases). More beneficial responses are observed for the new generation of transient scenarios for both wheat and sunflower. Area averaged results for Europe, based on the United Kingdom Meterorological Office transient experiment (UKTR), indicate a rate of increase in winter wheat yields of 0.2 t ha^-1 decade^-1 up to the 2020s and 0.36 t ha^-1 decade^-1 beyond. Smaller changes are predicted for sunflower: a rate of decrease of 0.05 t ha^-1 decade^-1 up to the 2020s followed by an increase of 0.05 t ha^-1 decade^-1.

Spatial crop modelling · Climate change · Winter wheat · Sunflower