Climate impacts of afforestation in temperate regions: a regional assessment in Mongolia

Afforestation influences climate not only through carbon sequestration but also by altering surface albedo. In high-latitude regions, reductions in albedo associated with increased forest cover can induce warming that partially or fully offsets biomass-driven cooling. However, existing assessments of albedo impacts from reforestation in temperate regions largely rely on coarse-resolution, global-scale analyses, creating a significant gap between current scientific understanding and the practical evaluation of region-specific reforestation initiatives. Here, we investigate the net climate impacts of afforestation at the regional scale using three provinces in Mongolia as case studies. In contrast to earlier global-scale assessments, we apply regionally calibrated, albedo-related parameters that improve the representation of snow cover fraction and surface radiation processes. Our results indicate that afforestation in the three Mongolian provinces leads to net climate cooling, reversing conclusions drawn from previous global-scale assessments. This suggests that reliance on global-scale assessments may underestimate the climate benefits of afforestation in temperate regions, highlighting the importance of region-specific analyses for informing reforestation initiatives.