Estimating regional crop potential in Finland under a changing climate

A geographical analysis system is described for evaluating regional crop potential in Finland under possible future climatic change. The system comprises a data base and models of crop potential which are combined in a geographical information system. The data base includes information on administrative boundaries, physiographic features, climate, soils, land cover, agricultural land use and crop production. Agroclimatic indices and simple growth models are employed to compute the regional suitability for crop cultivation and potential productivity. These are depicted on a 10 km regular grid across Finland. As an example, the suitability of spring wheat (Triticum aestivum; cv. 'Kadett') is examined, both for present-day conditions and under a scenario of 0.3 degrees C warming per decade up to 2050. The results indicate that northward shifts in suitability ranging from 110 km per 1 degrees C warming in eastern Finland to 290 km degrees C-1 in western Finland could be anticipated. This represents a rate of extension of between 35 and 85 km per decade. At the same time, the duration of the heading to maturity phase shortens as the climate becomes warmer. Since this phase includes the grain filling period, a reduction in grain yields could be expected in warmer regions unless present-day cultivars were substituted by slower maturing and higher yielding cultivars.