Abstract ID: 3.8232 | Accepted as Talk | Talk/Oral | TBA | TBA

Mountain ecosystems are among the most vulnerable to climate change, with rising temperatures and shifting precipitation patterns driving profound transformations in biodiversity, hydrology, and ecosystem services. High-resolution environmental stratification (EnS) provides a powerful approach to modeling these changes by delineating bioclimatic strata that reflect current and future climate conditions. This study applies a statistically derived global framework, based on downscaled CMIP6 Earth System Model projections, to assess the magnitude and spatial distribution of bioclimatic shifts in mountainous regions worldwide. Projected climate changes indicate that mountain bioclimatic zones will experience significant shifts in elevation and latitudinal extent by mid-century (2041–2060). Cold and mesic zones, which currently dominate many high-altitude regions, are projected to contract substantially under high-emission scenarios. Conversely, temperate and xeric zones are expected to expand into higher elevations, leading to increased aridification and altered hydrological cycles in regions such as the Himalayas, Andes, Alps, and Rocky Mountains. These changes threaten endemic alpine biodiversity, accelerate glacial melt, and disrupt water availability for downstream communities reliant on mountain-fed river systems. The EnS approach enables a fine-scale assessment of ecosystem responses to change, providing insights into potential range contractions of cold and other niche-adapted species and the upward migration of vegetation zones. Additionally, environmental stratification allows for the evaluation of climate impacts on ecosystem services, such as carbon sequestration and water regulation, which are crucial for sustaining both mountain ecosystems and human populations. Our findings underscore the urgency of adaptive conservation strategies to mitigate biodiversity loss and ecosystem degradation in mountain regions. By leveraging high-resolution environmental stratification, this research offers a robust framework for policymakers and conservationists to anticipate and respond to climate-driven transformations in mountainous landscapes. The results provide critical guidance for regional adaptation planning, helping to safeguard biodiversity, water resources, and ecosystem stability in some of the world’s most climate-sensitive environments.