Enhanced biological carbon consumption in a high CO 2 ocean

Ocean carbon dioxide Nearly half of the fossil-fuel carbon dioxide produced since pre-industrial times has been absorbed by the oceans, causing measurable acidification and carbonate saturation. A series of recent reports has raised the spectre of severe seawater acidification in the future if anthropogenic CO2 production continues unchecked. Previous work has dealt largely with the effects on individual marine species. Now in an experimental study at Raune Fjord in Norway, using environment-scale mesocosm enclosures, the impact of CO2 absorption has been estimated in a natural community ecosystem. The results show that CO2 consumption by marine phytoplankton increases markedly as partial pressures of the gas increase, yet nutrient uptake is unchanged. If applicable to the oceans as a whole, this feedback might be an important constraint on atmospheric CO2 concentrations.