Enhancement of oceanic uptake of anthropogenic CO2 by macronutrient fertilization
Article first published online: 1 APR 2004
Copyright 2004 by the American Geophysical Union.
Journal of Geophysical Research: Oceans (1978–2012)
Volume 109, Issue C4, April 2004
How to Cite
2004), Enhancement of oceanic uptake of anthropogenic CO2 by macronutrient fertilization, J. Geophys. Res., 109, C04001, doi:10.1029/2000JC000321., and (
- Issue published online: 1 APR 2004
- Article first published online: 1 APR 2004
- Manuscript Accepted: 30 DEC 2003
- Manuscript Revised: 8 DEC 2003
- Manuscript Received: 20 MAR 2000
 A global three-dimensional ocean carbon cycle model was used to investigate the use of macronutrient fertilization of the ocean to increase the oceanic uptake of CO2. To simulate macronutrient fertilization, phosphate was added to the 18°–50°S surface ocean. The carbon sequestration efficiency of fertilization was determined from the ratio of increased ocean uptake of anthropogenic CO2 to the rate of phosphate addition to the upper ocean (converted to carbon units using the C/P ratio of organic matter, 106). The model simulation produced a maximum efficiency of 78%. However, the simulations demonstrated that changes in calcium carbon production with macronutrient fertilization could significantly reduce carbon sequestration efficiency. When calcium carbonate production increases at the same rate as export production, the carbon sequestration efficiency is reduced by 25% when compared to a simulation where calcium carbonate production is held constant. The study also discusses several other potential process that could impact the efficiency phosphate fertilization to sequester carbon in the ocean and the potential consequences of large-scale macronutrient fertilization of the ocean.