Ocean nourishment

See also: Iron fertilization

Ocean Nourishment is a type of geoengineering based on the purposeful introduction of nutrients to the upper ocean ^[1] to increase marine food production ^[2] and to sequester carbon dioxide from the atmosphere. Fertilization can also potentially create sulfur aerosols which reduce the rate of global warming. The marine food chain is based on photosynthesis by marine phytoplankton which combine carbon with inorganic nutrients to produce organic matter. The production of organic matter is limited in general by the availability of nutrients, most commonly nitrogen or iron. Numerous experiments^[3] have been carried out demonstrating how iron fertilization can increase phytoplankton productivity. Nitrogen is a limiting nutrient over much of the ocean and can be supplied by from a number of sources including fixation by cyanobacteria. Carbon-to-iron ratios in phytoplankton are much larger than carbon-to-nitrogen or carbon-to-phosphorus ratios, so iron has the highest potential for sequestration per unit mass added.

Ocean Nourishment offers the prospect of both reducing the concentration of atmospheric greenhouse gases with the aim of avoiding dangerous climate change and at the same time increasing the sustainable fish stocks. It promises to do this by increasing the ocean primary production.

Ocean Nourishment promises to be a way of creating low cost protein in sufficient quantity to supply the needs of the additional two billion people expected to populate the earth before the population stabilizes at values near eight billion.^{[citation needed]} While manipulation of the land ecosystem in support of agriculture for the benefit of humans has long been accepted it is a new concept to enhance the large scale ocean productivity and so creates some apprehension.

Phosphorus fertilization

This technique can give 0.83W/m² of globally averaged negative forcing,^[4] which is sufficient to reverse the warming effect of about half the current levels of anthropogenic CO₂ emissions. It is notable, however, that CO₂ levels will have risen by the time this could be achieved.

Nitrogen fertilization

Proposed by Ian Jones with the purpose to fertilize the ocean with urea, a nitrogen rich substance, to encourage phytoplankton growth.^{[citation needed]} Also considered by Karl.^[5]

An Australian company, Ocean Nourishment Corporation (ONC), plans to sink hundreds of tonnes of urea into the ocean, in order to boost the growth of CO₂-absorbing phytoplankton, as a way to combat climate change. In 2007, Sydney-based ONC completed an experiment involving one tonne of nitrogen in the Sulu Sea off the Philippines.^[6]

This technique can give 0.38W/m² of globally averaged negative forcing,^[4] which is sufficient to reverse the warming effect of current levels of around a quarter of anthropogenic CO₂ emissions. It is notable, however, that CO₂ levels will have risen by the time this could be achieved.

Sulu sea urea fertilization advantages and disadvantages

Advantages

"Ocean Nourishment Corporation has claimed that in the long run, beyond Sulu Sea trials, “One Ocean Nourishment plant will remove approximately 5-8 million tonnes of CO2 from the atmosphere for each year of operation, equivalent to offsetting annual emissions from a typical 1200 MW coal-fired power station or the short-term sequestration from million hectares of new growth forest”.^[7]

Disadvantages

Nitrogen fertilization is not as efficient as iron fertilization.

Algal cell chemical composition is 106 carbon: 16 nitrogen: 1 phosphorus: 0.0001 iron. In other words for each atom of iron there are 1060000 atoms of carbon are captured, however for one nitrogen atom only 6 atoms of carbon are captured.

Urea fertilization may not benefit fisheries

It has been said that addition of urea to the ocean can cause blooms of phytoplankton that is source of food of fish. However, if cyanobactaria and dinoflagellates dominate the phytoplankton assemblage that are considered poor quality food for fish then fish quantity cannot be counted as rising. Another disadvantage is the fact that fossil fuels are used to produce urea. The fossil fuels contain buried CO2, so using them is not benign from the environmental point of view. ^[8]

Sulu sea biodiversity

In Sulu Sea Tubbataha’s marine biodiversity is virtually unparalleled by any other in the world today ^[9] and nitrogen loading in coral reef areas can lead to community shifts towards algal overgrowth of corals and ecosystem disruption.^[10] This makes Sulu sea unlikely candidate for urea fertilization experiment.

Ocean nourishment and International Law

Iron, urea, or phosphorus fertilization of ocean is thought to be dilemma looking from international law perspective. From one perspective United Nations Framework Convention on Climate Change(UNFCCC 1992) has accepted to make mitigation acts if amount exceeds normal quantity where climate change can adapt. On the other hand international law protects and preserve marine environment from scientific uncertainty. Some commercial companies like Climos and GreenSea Ventures, and Australian based Ocean Nourishment Corporation, are to engage in urea and iron fertilization process. These companies invite green co-sponsors to finance their activities in return for provision of carbon credits to offset investors’ CO2 emissions. ^[11]

According to David Freestone and Rosemary Rayfuse in June 2007 London convention issued a Statement of concern noting 'the potential for large scale ocean iron fertilization to have negative impacts on the marine environment and human health'. But word 'large scale' was not defined properly. It is believed that large scale would refer to operations on the scale then planned by Planktos.Planktos is USA-based company, recently abandoned its plans to conduct 6 fertilzation cruises from 2007 2009, each of which would have dissolved up to 100 t of iron over a 10,000 km^2 tract of ocean.^[12]

UN Intergovernmental Panel on Climate Change has examined the ocean fertilization issue and determined that it should not be pursued because there is very little documented increase in actual long-term sequestration of CO2 in the deep waters or sediments. ^[13]

To reduce carbon and greenhousegas emissions any country should met UNFCCC and Kyoto Protocol criteria. However Kyoto protocol do not accept any form of carbon sink projects except the forestation and reforestation projects.

Law of sea issues

According to United Nations Convention on the Law of the Sea(LOSC 1982), all states are obliged to take individually and jointly all measures necessary to prevent, reduce and control pollution of the marine environment, to prohibit the transfer, either directly or indirectly, of damage or hazards from one area to another, and to prohibit the transformation of one type pollution to another. Without deep research it is not clear to say that fertilization of oceans are safe way to fight against carbon and greenhousegas emissions.

Solar radiation management

Main article: solar radiation management

As well as carbon sequestration, ocean fertilization can also be used to create sulfate aerosols which reflect sunlight and modify the Earth's albedo, this creating a cooling effect which reduces some of the effects of climate change. Enhancing the natural sulfur cycle in the Southern Ocean^[14] ocean by fertilizing a small portion with iron in order to enhance dimethyl sulfide production and cloud reflectivity achieves this. The goal is to slow Antarctic ice from melting and raising sea level.^[15][16] Such techniques also tend to sequester carbon, but in this specific project the enhancement of cloud albedo was both the desired outcome and measured result.^[17]

See also

• Iron fertilization
• Carbon dioxide sink
• Geoengineering
• Planetary engineering

References

1. ^ Matear, R. J., and B. Elliott (2004). "Enhancement of oceanic uptake of anthropogenic CO2 by macronutrient fertilization". J. Geophys. Res. 109 (C4): C04001. Bibcode 2004JGRC..10904001M. doi:10.1029/2000JC000321. http://www.agu.org/pubs/crossref/2004/2000JC000321.shtml. 
2. ^ Jones, I.S.F. & Young, H.E. (1997). "Engineering a large sustainable world fishery". Environmental Conservation 24 (2): 99–104. doi:10.1017/S0376892997000167. 
3. ^ Coale KH, Johnson KS, Fitzwater SE, et al. (October 1996). "A massive phytoplankton bloom induced by an ecosystem-scale iron fertilization experiment in the equatorial Pacific Ocean". Nature 383 (6600): 495–501. Bibcode 1996Natur.383..495C. doi:10.1038/383495a0. PMID 18680864. 
4. ^ ^{a b} Lenton, T. M., Vaughan, N. E. (2009). "The radiative forcing potential of different climate geoengineering options". Atmos. Chem. Phys. Discuss. 9 (1): 2559–2608. doi:10.5194/acpd-9-2559-2009. http://www.atmos-chem-phys-discuss.net/9/2559/2009/acpd-9-2559-2009.pdf. 
5. ^ Karl, D. M. and Letelier, R. (2008). "Nitrogen fixation-enhanced carbon sequestration in low nitrate, low chlorophyll seascapes". Mar. Ecol.-Prog. Ser. 364: 257–268. doi:10.3354/meps07547. 
6. ^ Anna Salleh (9 November 2007). "Urea 'climate solution' may backfire". ABC Science: In Depth. Australian Broadcasting Commission. http://www.abc.net.au/science/articles/2007/11/09/2085584.htm. 
7. ^ http://www.oceannourishment.com/technology.asp)
8. ^ Glibert, P M. (2008). Ocean urea fertilization for carbon credits poses high ecological risks. Marine pollution bulletin, 56(6), 1049-1056.
9. ^ Mission, G., 1999. WWF’s marine police: saving Sulu Sea. http://gina.ph/CyberDyaryo/features/cd1999_0930_005.htm
10. ^ Smith, S.V., Kimmerer, W.J., E.A., Brock, R.E., Walsh, T.W., 1981. Kaneohe Bay sewage diversion experiment: perspectives on ecosystem responses to nutritional perturbation. Pacific Science 35, 279-395.
11. ^ Salleh A (2007( Urea ‘climate solution’ may backfire. ABC Science Online, 9 November 2007, available at http://www.abc.net.au/science/news/stories/2007/2085584.htm
12. ^ Planktos (2007) Planktos sharehodle update. Business wire, 19 December 2007. Available at; http://www.pr-inside.com/planktos-shareholder-update-r356198.htm
13. ^ (IPCC; http://www.ipcc.ch/)
14. ^ Wingenter, Oliver W.; Elliot, Scott M.; Blake, Donald R. (November 2007). "New Directions: Enhancing the natural sulfur cycle to slow global warming". Atmospheric Environment 41 (34): 7373–5. doi:10.1016/j.atmosenv.2007.07.021. A
15. ^ http://www.climos.com/news/articles/slowingglobal.htm
16. ^ Coale, K. H.; Johnson, K. S.; Buesseler, K.; Sofex Group. "SOFeX: Southern Ocean Iron Experiments. Overview and Experimental Design". American Geophysical Union. Fall Meeting 2002. Bibcode 2002AGUFMOS22D..01C. 2002AGUFMOS22D..01C. 
17. ^ T. S. Bates, B. K. Lamb, A. Guenther, J. Dignon,R. E. Stoiber (1992). "Sulfur Emissions to the Atmosphere from Natural Sources". Journal of Atmospheric Chemistry 14 (1-4): 315–337. doi:10.1007/BF00115242. http://www.pmel.noaa.gov/pubs/outstand/bate1229/estimate.shtml.