Mitteilungen der Gesellschaft für Pflanzenbauwissenschaften Band 23

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impact assessment revealed that climate change will reduce crop yields which will,
however, differ depending on the crop and region. Simulated climate change impacts
were more pronounced for spring as compared to winter crops. Consideration of the
effects of increasing CO2 concentration and technology development resulted in yield
increases as compared to the baseline for all crops except maize, and differed
depending on the scenario and the region. Our simulations also suggest some
increase in yield variability due to climate change which, however, is less pronounced
than the differences among scenarios which are particularly large when the effects of
CO2 concentration and technology development are taken into account. Our results
clearly stress the need for region-specific calibration of crop models used for pan-
European assessments. We conclude that future work should focus on obtaining
better data and improved methods for model calibration to account for spatial
differences but also temporal changes in development and growth parameters as
used in crop models.
a. b. c.
Fig. 1: Comparison between observed and simulated yields from three calibration
methods; (a) phenology only, (b) using a yield correction factor, and (c) an extended
calibration of selected growth parameters of winter wheat for 533 climate zones in
Europe in the period from 1983 to 2006. See text for explanation of calibration
methods.
References
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