Abstract
Biodiversity researchers usually use projections from climate models to assess future risks associated with changes in the distribution of species and the composition of ecological communities. However, selecting the scenarios underlying these projections without a detailed understanding of their inherent assumptions carries risks. In this Perspective, we examine what climate-change scenarios are, what parts of these scenarios are useful for biodiversity research, which scenarios map most closely onto policy agendas, and how biodiversity researchers can make the best use of projections of future climate generated from these scenarios. Closer inspection of climate-change scenarios reveals hidden complexity that can confound even specialists and spark debate about their plausibility, but with careful caveats, biodiversity researchers can rely on the climate projections produced from these scenarios. Scenarios based on technological interventions designed to actively cool the climate are of increasing interest to policymakers owing to society’s ongoing failure to act decisively on emissions reduction. Projected responses of biodiversity to climate change will be most valuable to society when they address plausible futures targeted by policymakers. We aim to facilitate this goal with accessible discussions and pragmatic recommendations that are targeted specifically at the biodiversity research community.