Projected shifts in climate and spring barley yields under future (CMIP6) scenarios across eight environmental zones in Europe

Breeding of climate-resilient barley cultivars requires knowledge about shifts in climate hazards and potential yield impacts. This Europe-wide study aims to provide such information by using the latest (CMIP6) climate scenarios (six Global Climate Models x two emission scenarios SSP1-2.6 & SSP5-8.5 x two time slices, 2050s and 2080s) for crop model-based yield projections and generation of agroclimatic indicators to characterize climate-induced hazards and likely impacts on spring barley production conditions across environments within Europe. The results from analyses of 19 different sites were aggregated over eight environmental zones across Europe. For all zones, we found elevated growing season temperatures, which were associated with increased likelihoods of heat hazards across most zones. Phenological development was consequently accelerated, resulting in yield penalties across most zones, with up to 31 % yield reduction in the Mediterranean south under high emission scenarios for the 2080s. Such simulated losses were found to be compensated by CO 2 fertilisation effects under high emission scenarios (at 868 ppm CO 2 ). However, the fertilization effect was not uniform across zones and might mask production losses that are related to an increased exposure to extreme growing conditions not captured by the crop model. Based on our results, it can be concluded that rainfed barley production in Europe will very likely face more climate-related hazards, especially related to heat. This emphasizes the need for designing adaptation strategies that combine climate-resilient crop cultivars tailored to evolving climatic hazard combinations with sustainable management practices that are adapted to local conditions.