Rate Of CO2 Release From Warming Oceans Faster Than Thought, Though Still Measured In Centuries - NS

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As the world's oceans warm, their massive stores of dissolved carbon dioxide may be quick to bubble back out into the atmosphere and amplify the greenhouse effect, according to a new study.

The oceans capture around 30 per cent of human carbon dioxide emissions and hide it in their depths. This slows the march of global warming somewhat. But climate records from the end of the last ice age show that as temperatures climb, the trend reverses and the oceans emit CO2, which exacerbates warming.

Previous studies have suggested that it takes between 400 and 1300 years for this to happen. But now the most precise analysis to date has whittled that figure down. "We now think the delay is more like 200 years, possibly even less," says Tas van Ommen from the Australian Antarctic Division, in Hobart, who led the study.

The new results come from Siple and Byrd ice cores in western Antarctica. Van Ommen and colleagues dated CO2 bubbles trapped in the ice, and then compared their measurements with records of atmospheric temperatures from the same time period. As expected, when temperature increased, carbon dioxide followed, but at both Siple and Byrd the time lag was around 200 years – much shorter than previous studies found.

EDIT

http://www.newscientist.com/article/dn20413-warmer-oceans-release-co2-faster-than-thought.html