Why can the climate effects of deforestation differ between tropical and middle-latitude regions?

The climate effects of deforestation are driven by the interplay between two primary factors: albedo (surface reflectance) and evapotranspiration. The relative dominance of these factors varies by region, leading to different climatic outcomes.1

• Middle Latitudes: In these regions, the albedo effect generally dominates, particularly from autumn through spring. When forests are replaced by cropland or pasture, the surface becomes more reflective, leading to greater reflection of incoming solar radiation and a net cooling effect. While evapotranspiration can exert a warming influence during the summer, the albedo-driven cooling is typically the primary factor in the midlatitudes.1
• Tropical Regions: In the tropics, the cooling effect of albedo is often countered by the loss of latent heat release through evapotranspiration. Because tropical forests facilitate significant water vapor release into the atmosphere year-round, their removal can lead to surface warming. Consequently, in the tropics, the evapotranspiration effect is a critical factor in assessing the climate impacts of deforestation.1

Beyond these regional differences, deforestation globally contributes to global warming by reducing the capacity for carbon sequestration and releasing stored carbon into the atmosphere as carbon dioxide.12