Researchers at the National Oceanography Centre at the University of Southampton, England, have found that coccolithophores, a microscopic marine organism once thought to be the key to solving global warming, may actually have little effect on carbon dioxide levels, the journal Nature reported. This conclusion could have important implications for biogeochemical modeling of the Earth’s future climate.
The microorganisms are usually found in the uppermost layers of oceans. Coccolithophores account for about a third of the total marine calcium carbonate production. The organisms use calcium carbonate to build plates to protect themselves. During this process, there is a net consumption of carbon dioxide.
This use of carbon dioxide may significantly impact the ocean’s ecology and the atmosphere as carbon dioxide is currently rising to unprecedented levels.
The joint team of researchers from Southampton and the University of Oxford also found, though, that the organisms might actually have little impact on rising greenhouse gas levels. Field evidence shows that over the past 220 years there has been a 40 percent increase in average coccolithophore mass, the Nature article said. A study at the University of Delaware concluded that there was significant response from marine coccolithophores to strong increases in carbon dioxide, which coincided in an increase in their rate of photosynthesis. This increase resulted in the production of an amount of carbon dioxide equal to the amount consumed by the organism.
“It is unlikely that coccolithophores are going to be mitigating or exacerbating the rise of carbon dioxide in the atmosphere,” University of Southampton professor M. Debora Iglesias-Roderiguez, who led the study, told Nature.
Further reading:
Courtland, Rachel. “Phytoplankton Responding to Climate Change.” Nature. 17 April 2008. http://www.nature.com/news/2008/080417/full/news.2008/760.html
Feng, Yuanyuan, et al. “Interactive effects of increased pCO2, temperature and irradiance on the marine coccolithophore Emiliania huxleyi.” European Journal of Phycology. Taylor & Francis Group. 2008.
Iglesias-Rodriguez, M. Debora et al. “Phytoplankton Calcification in a High-CO2 World.” Science 18 April 2008: Vol. 320. no. 5874, pp. 336 – 340.