The intricate links between human and Earth systems are being increasingly represented in coupled human-Earth system models. These models can then be used to explore the two-way feedbacks between the human and Earth systems due to changes in land productivity, water availability, extreme climatic events, land use/land cover, and greenhouse gas emissions. DOE’s state-of-the-science Energy Exascale Earth System Model (E3SM) has been fully coupled with the Global Change Assessment Model (GCAM): terrestrial productivity is passed from E3SM to GCAM, which then projects land use/land cover change and CO₂ emission, outputs that are passed back to the E3SM land and atmosphere components every five years. We use the coupled E3SM-GCAM model to study the impact of a land use/land cover change associated with different radiative forcing scenarios on the carbon cycle. The impact of climate change on these scenarios, and the feedbacks between the two systems. In the future, the study will be expanded to include feasible decarbonization scenarios, for reaching net zero CO₂ emissions by 2050, to quantify the impact of decarbonization pathways on biogeochemical cycles and feedbacks to the Earth system.