The study on surface marine CO2 levels in the Atlantic Ocean shows a 50% reduction in the ocean's capacity to soak up greenhouse gases.
"Such large changes are a tremendous surprise. We expected that the uptake would change only slowly because of the ocean's great mass," said Dr Ute Schuster, who has been involved in the research since 2000. The results of the survey, conducted between 1995 and 2005 by scientists at the University of East Anglia (UK), will be published in the Journal of Geophysical Research this week.
The oceans, together with the land biosphere, are major carbon "sinks" for CO2 emissions. Together, they absorb some 50% of all the CO2 emitted into the atmosphere. According to the researchers, oceans soaking up less CO2 will lead to a faster increase in CO2 levels in the atmosphere and increase the rate of global warming.
Scientists are also concerned that the oceans may in time become saturated with CO2 and begin reflecting the gas back into the atmosphere.
Asked whether, based on these alarming results in the North Atlantic, the research could be extended to the South Atlantic as well, Dr Ute Schuster told EurActiv that "the interest is definitely growing" but that "the absence of regular lines for trade ships is a problem for conducting such extensive research at the South Atlantic. In the absence of merchant ships, we could consider placing measurement devices on immobile drifting buoys there," she said.
The data for North Atlantic was collected by merchant ships, and in particular one container ship carrying bananas from the West Indies to the UK, that regularly sail there equipped with specific devices for measuring CO2 levels.
Regarding the future of research on surface marine CO2 in the Atlantic Ocean, Schuster said that "instruments are in place and still running."
The research conducted by scientists at the University of East Anglia is part of an EU-funded project called CarboOcean, which targets accurate scientific assessment of marine carbon sources and sinks within space and time.
