Diverse Combined Land‐Atmosphere Dryness Changes Following Deforestation

Abstract Forests sustain regional humid climates crucial for the Earth System. Deforestation, through biophysical and biochemical processes, alters regional climates, particularly impacting aridity. However, deforestation's comprehensive impacts on land‐atmosphere interactions and aridity remain unclear. An idealized deforestation experiment was used to isolate its impacts. We focus on combined changes in Soil Moisture (SM) and Vapor Pressure Deficit (VPD) as indicators of land‐atmosphere system aridity. Results show that the Northern Hemisphere experiences a wetter land‐atmosphere system (62.3%) following deforestation, with increased SM and decreased VPD. Over 30% of regions exhibit weakened land‐atmosphere coupling, highlighting enhanced limitations in SM. Drier systems occur more in non‐arid areas, while arid regions tend to become wetter. The study also examines the physical processes underlying these changes in two contrasting regions: the drier India and the wetter Europe. Findings offer policymakers insights into regional variations in SM and VPD responses when making ecological and agricultural policies.