 This study investigates the potential to predict variations in terrestrial carbon fluxes up to 10 years in advance using a novel set of retrospective decadal forecasts from an Earth system model and demonstrates that globally integrated net ecosystem production exhibits high predictability for two years following initialization, with potential predictability deriving mainly from high predictability in ecosystem respiration driven by vegetation carbon and soil moisture initialization. This article was authored by Nicole S. Lovendusky, Gordon B. Bonin, Stephen G. Jaeger, and others.