Horizontal and vertical removal of organic carbon in the equatorial Pacific Ocean: a mass balance assessment

Mass balance calculations were performed to assess the relative contributions of vertical export and horizontal advection of organic carbon and nitrogen from the central and western equatorial Pacific Ocean. The results of the analyses indicate that approximately 20% of the net community production in the region accumulates in the surface layer as suspended or dissolved organic matter. It is these fractions that have the potential to be removed from the equator via advection. The balance of net community production (approximately 80%) must be exported vertically as sinking organic particles. Using published estimates of new production in the equatorial Pacific during 1992, we estimate net organic carbon production available for removal from the equator by horizontal advection during that period to have been 0.07 – 0.18 Pg C year−1.