The CNR Institute for Marine Sciences (Ismar) and the Geomar Helmholtz Centre for Ocean Research of Kiel have recently conducted a study that sheds new light on the marine carbon cycle. This is the mechanism, known as the “biological carbon pump” (BCP), which transports CO2 from superficial waters to the deep sea away from the atmosphere and which is crucially important to reduce the level of carbon dioxide in the atmosphere.
According to the team of researchers who participated in the study, to quantify this process it is necessary to consider not only how much CO2 is stored in the deep sea, but also how much carbon dioxide returns into the atmosphere due to ocean circulation. This is a conclusion that would lead researchers to dispel the idea that there is a direct link between the so-called “export production” and the biological carbon storage in the deep ocean.
A simpler and more direct estimate of CO2 storage in the deep sea is possible by measuring the content of oxygen therein dissolved. “The ocean plays a key role in storing carbon dioxide; however, when the quantity is determined, the crucial role of ocean circulation is often neglected: it is the latter that actually determines the quantity of CO2 that can be accumulated in the long term in the ocean and isolated by the atmosphere,” explained Angela Landolfi, CNR-Ismar researcher and among the study authors. The variations in ocean circulation help explain the reason why the BCP mechanism is increasing today.However, Landolfi warns that “The effect that counteracts atmospheric CO2 increase due to the biological carbon pump is unfortunately small when compared with the anthropogenic emissions of CO2 from fossil fuels.”
For further information about the study, please click here.