The ocean mitigates climate change by absorbing about 25 % of the carbon that is emitted to the atmosphere. However, ocean CO₂ uptake is not constant in time, and improving our understanding of the mechanisms regulating this variability can potentially lead to a better predictive capability of its future behavior. In this study, we compare two ocean modeling practices that are used to reconstruct the historical ocean carbon uptake, demonstrating the abilities of one over the other.