PARIS, Sept 25 — The surface of marine waters is made up of a thin film that scientists refer to as "ocean skin.” And this skin could play an invaluable role in slowing global warming. According to CNRS researchers, it could absorb 5-15 per cent of greenhouse gas emissions.

It measures less than a millimetre, but it has an essential role. Known as "ocean skin,” the thin layer that separates the surrounding air from marine waters has recently been the subject of a study published by the French National Centre for Scientific Research (CNRS). Along with forests, oceans are the planet’s most important carbon sinks. And the films that cover the surface of marine waters alone could capture significant quantities of greenhouse gas emissions from the atmosphere. To reach this conclusion, the research team used a simulation from an Earth System Model.

The model enabled the researchers to obtain an interactive and "physical representation of the ocean surface levels” in order to study the exchange of carbon dioxide between the ocean and the atmosphere. The scientists found a 15 per cent increase in the simulated global ocean carbon sink. "This result confirms the important impact of ocean skin on the global carbon sink suggested by previous studies,” they emphasise in a press release.

First described in the 1960s, ocean skin has long been at the centre of debate as to the extent to which it contributes to carbon storage. Its temperature is around -0.2 degrees Celsius cooler and its salinity slightly higher than the water it covers. It is precisely these two characteristics that enable it to capture CO2. "Taking into account these temperature and salinity changes in this thin layer can change calculations of the global ocean carbon sink substantially,” explain the CNRS researchers.

They found, however, that the ocean skin’s capacity to store carbon decreased by 5 per cent when variations in ocean carbon concentrations were incorporated into the model on which the study was based. "However, this impact remains non-negligible globally and regionally. It should therefore be taken into account in future work of comparisons using models as well as global carbon assessments,” the authors conclude. — ETX Studio