Abstract Current climate change exerts significant impacts on global ecosystems and is expected to reshape species distributions in the future. Climate Envelope Models (CEMs) are widely used to simulate potential shifts in species ranges under varying climatic conditions. This study aims to quantify the relative importance of key assumptions embedded within CEMs on projections of distributional changes for European vertebrates. This allows us to identify the factors most crucial to the survival of populations and thus to conservation strategies. We analysed variance on published CEM results to estimate effect sizes associated with different modelling assumptions, including the climate model used and the incorporation of dispersal constraints. The capacity for species dispersal emerged as the most influential factor affecting predicted range shifts, followed by assumptions related to atmospheric and oceanic circulation dynamics and anthropogenic emission scenarios. Additionally, taxonomic group-specific traits exerted a statistically significant, albeit smaller, effect. No significant differences were detected between projections for 2050 and 2080. Our findings emphasise that habitat conservation and the maintenance of ecological corridors will be critical for the persistence of many European vertebrate species amid rapidly changing climatic conditions.
Kubich et al. (Fri,) studied this question.