Assessing the Climate Impacts of Large‐Scale Global Adoption of Cover Crops and Agroforestry

Abstract Cover crops and agroforestry are gaining prominence as climate‐smart agricultural practices, offering mitigation and adaptation benefits through enhanced carbon sequestration, improved soil health, and biodiversity conservation. However, the biogeophysical climate impacts from the changes they induce in the surface energy balance are insufficiently understood. This study uses a coupled atmosphere‐land model and field‐based observations to investigate the upper‐bound climate impacts from large‐scale global adoption of these practices. Replacing bare soil with cover crops in winter reduces near‐surface air temperature by about −0.3 ± 0.11°C in snow‐free regions, primarily due to increased latent heat flux. In snow‐covered regions, temperature responses are more variable due to albedo changes. Leafier and taller non‐leguminous crops induce stronger cooling than legumes under both snow‐free and snow‐covered conditions. Agroforestry induces year‐round cooling in the tropics (up to −0.14 ± 0.05°C annually) and warming in most extratropical areas due to snow‐albedo feedbacks. The biogeophysical warming outside the tropics can be offset by the cooling contributions from increased carbon sequestration in vegetation and soil, and in snow‐free areas biogeophysical cooling reinforces these benefits. Climate effects remain similar even when cover crops or agroforestry are applied across twice the cropland area, highlighting nonlinear system responses and opportunities to optimize cooling benefits through selective deployment. These findings underscore the importance of accounting for both biogeophysical and biogeochemical processes when evaluating sustainable agricultural practices and their capacity to support a transition toward climate change resilient agricultural systems that align local adaptation needs with long‐term global climate mitigation goal.