Identifying global marine climate refugia through a conservative approach to ocean biodiversity preservation.

Abstract

Global changes threaten marine species, making marine climate refugia essential for biodiversity conservation and climate change mitigation. Our analysis maps sensitive and stability zones across the global ocean. We define marine climate refugia as climate-resilient zones with global conservation consensus under the worst-case emissions scenario for 2100. Marine climate refugia span 17.6 million square kilometres, with 96% within exclusive economic zones. Only 34% of oceanic areas and 29% of marine protected areas (MPAs) and other effective area-based conservation measures (OECMs) lie in stability zones. Twenty large-scale patches form the principal bodies of marine climate refugia, with 85% crossing multiple exclusive economic zones. Conservation gaps cover 70% of marine climate refugia. Closing these gaps could increase global ocean protection to 14% and exclusive economic zones protection to 30%. To achieve the 30 by 30 target, we recommend expanding MPAs and OECMs based on marine climate refugia locations and addressing transnational management challenges.