Crop growth modelling and crop yield forecasting using satellite-derived meteorological inputs

Distributed crop simulation models are typically confronted with considerable uncertainty in weather variables. In this paper the use of MeteoSat-derived meteorological products to replace weather variables interpolated from weather stations (temperature, reference evapotranspiration and radiation) is explored. Simulations for winter-wheat were carried for Spain, Poland and Belgium using both interpolated and MeteoSat-derived weather variables. The results were spatially aggregated to national and regional level and were evaluated by comparing the simulation results of both approaches and by assessing the relationships with crop yield statistics over the periods 1995-2003 from EUROSTAT. The results indicate that potential crop yield can be simulated well using MeteoSat-derived meteorological variables, but that water-stress hardly occurs in the water-limited simulations. This is caused by a difference in reference evapotranspiration which was 20-30% smaller in case of MeteoSat. As a result, the simulations using MeteoSat-derived meteorological variables performed considerably poorer in a regression analyses with crop yield statistics on national and regional level. Our results indicate that a recalibration of the model parameters is necessary before the MeteoSat-derived meteorological variables can be used operationally in the system. (C) 2007 Published by Elsevier B.V.