Observed northward migration of agro-climate zones in Europe will further accelerate under climate change

Abstract

This study focuses on the northward shift of homogeneous agro-climate zones in Europeanalyzed for the observed past and projected climate conditions for the next decades. Statisticalcluster analysis is used to derive eight main agro-climatic zones driven by two agro-meteorologicalindicators, namely, active temperature sum and thermal growing season length. The northward shift ofhomogeneous agro-climate zones and the corresponding change of crop growth suitability are analyzedtogether with the change of exposure of crops to temperature-related climate extremes during the growingseason. Gradual warming over Europe has contributed to a lengthening of the growing season and anincreased active temperature accumulation, accompanied by more frequent occurrence of warm extremeclimate events. Using a set of five high-resolutionregional climate scenarios, we calculate that a major partof Europe will be affected by further northward climate zone migration. In the next decades, the migrationof agro-climatic zones in Eastern Europe may reach twice the velocity observed during the period1975–2016. Several regions of the Mediterranean may lose suitability to grow specific crops in favor ofnorthern European regions. This indicator-based assessment suggests that the potential advantages of thelengthening of the thermal growing season in northern and eastern Europe are often outbalanced by therisk of late frost and increased risk of early spring and summer heat waves.