Forestation, a strategy that includes afforestation and restoration, is critical for climate mitigation. While its local carbon sequestration potential receives widespread focus, its global biophysical effects mediated by land-atmosphere feedbacks and large-scale circulation changes remain poorly quantified. Existing research on these biophysical impacts has focused narrowly on local albedo changes, a framework that is incomplete because it neglects the Earth system’s intrinsic energy rebalancing via atmospheric circulation. To address this gap, we use a fully coupled Community Earth System Model (CESM2) to isolate the forestation-driven hydroclimatic response. Using an ideal global forestation scenario dominated by mid-high-latitudes, we quantify how forestation-induced hemispheric energy imbalances trigger a northward shift in the Intertropical Convergence Zone (ITCZ), establishing a teleconnection pathway. Our results show that mid-high latitude dominated forestation affects tropical water in a spatially heterogeneous manner, with a seasonal contrast of boreal summer increases versus winter decreases. This study aims to provide the essential Earth system perspective in understanding forestation’s hydroclimate impacts. Integrating this perspective is essential to designing forestation policies that contribute to climate stabilization without inadvertently redistributing water scarcity across vulnerable regions.