The flux of organic carbon associated with new production has been modeled by advection of dissolved organic carbon in addition to falling particulate organic carbon, in a carbon cycle model that is based on an oceanic general circulation model. Model predictions of chemical species involved in the carbon cycle are compared with observations. Relative to a model in which new production is carried only by falling particulate organic carbon, there is significantly better agreement between predicted and observed oceanic phosphate and oxygen concentrations if a large part of the new production flux is carried by dissolved organic carbon.