Air–sea CO₂ fluxes and associated uncertainty over the open ocean to coastal shelves are estimated with a new ensemble-based reconstruction of pCO₂ trained on observation-based data. The regional distribution and seasonality of CO₂ sources and sinks are consistent with those suggested in previous studies as well as mechanisms discussed therein. The ensemble-based uncertainty field allows identifying critical regions where improvements in pCO₂ and air–sea CO₂ flux estimates should be a priority.