Ocean absorbing more CO2 than previous studies had suggested

The ocean absorbs a lot more carbon dioxide from the atmosphere than previously thought, suggesting certain climate models were wrong, according to a new study.

Carbon emissions from human activity does not just go straight into the atmosphere, causing the planet to heat up. While a large percentage of it does – roughly half – some of it is absorbed into the ocean. And now new research has found there has been some miscalculations on how much carbon dioxide is being absorbed by the ocean.

The cooler the ocean, the more CO2 it absorbs. However, just a few metres beneath the surface, the temperature of the ocean begins to drop drastically.

Now scientists believe previous estimates may have been as much as 10 percent off.

Professor Andrew Watson, of the University of Exeter’s Global Systems Institute, said: “Half of the carbon dioxide we emit doesn’t stay in the atmosphere but is taken up by the oceans and land vegetation ‘sinks’.

“Researchers have assembled a large database of near-surface carbon dioxide measurements — the ‘Surface Ocean Carbon Atlas’ — that can be used to calculate the flux of CO2 from the atmosphere into the ocean.

“Previous studies that have done this have, however, ignored small temperature differences between the surface of the ocean and the depth of a few meters where the measurements are made.

“Those differences are important because carbon dioxide solubility depends very strongly on temperature.

“We used satellite data to correct for these temperature differences, and when we do that it makes a big difference — we get a substantially larger flux going into the ocean.

“The difference in ocean uptake we calculate amounts to about 10 percent of global fossil fuel emissions.”

Dr Jamie Shutler, of the Centre for Geography and Environmental Science on Exeter’s Penryn Campus in Cornwall, added: “Our revised estimate agrees much better than previously with an independent method of calculating how much carbon dioxide is being taken up by the ocean.

“That method makes use of a global ocean survey by research ships over decades, to calculate how the inventory of carbon in the ocean has increased.

“These two ‘big data’ estimates of the ocean sink for CO2 now agree pretty well, which gives us added confidence in them.”

However, it is not good news for Earth that not as much CO2 is being ploughed into the atmosphere.

The more CO2 the ocean absorbs, the more acidic it becomes.

This can drastically change the delicate ecosystems as it can destroy coral reefs and damage marine life.

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