Zee Media Bureau
London: A new study has claimed that rising temperatures can increase the amount of greenhouse gases emitted naturally by the oceans.
The new study, published in the journal Nature Geoscience, pointed out that a lack of iron at the ocean surface can limit the effect of other key elements in helping plankton (tiny marine organisms) take up carbon.
Previous studies have shown that warming climates lower iron levels at the sea surface.
Plankton is responsible for the absorption of CO2 from the atmosphere at the ocean surface. It can lock away vast quantities of carbon naturally emitted by oceans.
“Iron is known to be a key nutrient for plankton, but we were surprised by the many ways in which iron affects the CO2 given off by the oceans,” said Laetitia Pichevin from University of Edinburgh in Britain.
Pichevin said: “If warming climates lower iron levels at the sea surface, as it occurred in the past, this is bad news for the environment.”
For the study, scientists studied a 26,000-year-old sediment core taken from the Gulf of California to find out how the ocean`s ability to take up atmospheric CO2 has changed over time.
They observed the concentrations of silicon and iron in the fossils of plankton in the sediment core.
Those periods when silicon was least abundant in ocean waters corresponded with relatively warm climates, low levels of atmospheric iron, and reduced CO2 uptake by the oceans` plankton.
The study is carried out by the University of Edinburgh, is the first to pinpoint a link between iron and other key marine elements involved in regulating atmospheric CO2 by the oceans.
(With Agency Inputs)