Southern Ocean is less efficient at exporting carbon than thought

May 28, 2013

The Southern Ocean is a major source of gas exchange between the atmosphere and the ocean, accounting for almost 20 percent of global ocean carbon dioxide (CO2) uptake.

Phytoplankton fix CO2, converting it to other , and some of this biogenic carbon sinks to the deeper ocean, where it is effectively removed from the atmosphere.

A better understanding of the rate of export of carbon particulate matter from the upper ocean is key to improving uncertainties in models that include the Southern Ocean's role in the carbon cycle.

While most studies of carbon transport in the Southern Ocean rely on models, Maiti et al. analyzed in situ carbon export data to reexamine the relationships used in models between primary production, export efficiency, and temperature. They find that no single model accurately estimated biological export of carbon in the Southern Ocean.

In particular, many models predict an increase in carbon flux with increasing primary productivity, but in fact, the observational data indicates that decreases with increasing productivity. The authors suggest that the may have a lower potential for biological export of carbon than models had indicated.

Explore further: Tropical depression 21W forms, Philippines under warnings

More information: "An inverse relationship between production and export efficiency in the Southern Ocean" Geophysical Research Letters, doi: 10.1002/grl.50219, 2013.

add to favorites email to friend print save as pdf

Related Stories

Dwindling buffer effect?

Mar 28, 2013

(Phys.org) —The Southern Ocean could absorb relatively less carbon dioxide in future if the global temperatures continue to rise as a result of human activities, as climate researchers from ETH Zurich demonstrate ...

Circulation changes in a warmer ocean

Feb 22, 2013

Circulation changes in a warmer ocean In a new study, scientists suggest that the pattern of ocean circulation was radically altered in the past when climates were warmer.

Recommended for you

Better forecasts for sea ice under climate change

22 hours ago

University of Adelaide-led research will help pinpoint the impact of waves on sea ice, which is vulnerable to climate change, particularly in the Arctic where it is rapidly retreating.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.