Environmental exposure of terrestrial biomes to global climate change: An n-dimensional approach

Terrestrial biomes, defined by unique climatic conditions and evolutionary histories, are increasingly vulnerable to global climate change. This study evaluates the exposure of Earth's 14 terrestrial biomes to climate change by characterizing their climatic boundaries using n-dimensional probabilistic methods. We analyzed precipitation and temperature data from the Global 200 project, combined with bioclimatic variables and climate models, to assess changes across historical, present, and future scenarios (Shared Socioeconomic Pathways: SSP1-2.6, SSP3-7.0, and SSP5-8.5). Using NicheROVER and NicheA, we quantified climatic overlap and projected non-overlapping regions under future climate scenarios. Our results reveal significant climatic specificity in temperature and precipitation ranges, with Flooded Grasslands & Savannas, Tropical & Subtropical Dry Broadleaf Forests, and Mangroves identified as the most exposed biomes. Geographic projections for 2040 highlight high-exposure regions near the equator, including the Neotropics, Central and Northern Africa, Southern Asia, Oceania, and Antarctica. These regions intersect with 2230 and 9091 protected areas under the SSP3-7.0 and SSP5-8.5 scenarios, respectively. This study underscores the importance of characterizing climatic boundaries to enhance ecosystem resilience estimates and inform biodiversity conservation strategies. By integrating niche modeling approaches, we provide a framework for identifying regions most vulnerable to climate change. Our findings emphasize the need for targeted conservation efforts, policy interventions, and fine-scale analyses to mitigate climate impacts on biodiversity, agriculture, and human health. We conclude that understanding biome-specific climatic boundaries is critical for addressing the global climate crisis and guiding adaptive management in the most exposed regions.