A new modeling approach published in the journal Carbon Balance and Management provides national-scale, spatially-explicit estimates of carbon stocks and fluxes within forest ecosystems under a range of future climate and land management scenarios. The approach, implemented in the SyncroSim modeling environment, links the LUCAS model of land-use and land-cover change with the CBM-CFS3 carbon budget model. By linking these two leading models, the approach is well suited to quantify the effectiveness of natural climate solution strategies, such as protecting old growth forests, reducing deforestation, altering harvesting patterns, and implementing reforestation programs. The approach is demonstrated for forests across the U.S. to estimate historical and future carbon stocks and fluxes under alternative land management and climate scenarios.