Southern Ocean outgassing affects the global carbon budget

Since it contains large amounts of carbon dioxide, the Southern Ocean surrounding Antarctica plays a highly important role in global climate. According to a new study led by the University of Gothenburg, storms over the waters of this ocean drive a massive outgassing of carbon dioxide into the atmosphere. 

Studying in greater depth the complex processes driving air-sea fluxes of gases in the Southern Ocean can provide a better understanding of climate change and lead to more accurate global climate models.

“The Southern Ocean is a key component of the Earth’s carbon budget. It accounts for 40–50% of the total mean annual ocean uptake of anthropogenic CO2,” wrote the study authors.

Since climate change causes increasingly frequent storms, it is vital to understand the storms’ impact on the outgassing of carbon dioxide into the atmosphere.

“We show how the intense storms that often occur in the region increase ocean mixing and bring carbon dioxide-rich waters from the deep to the surface. This drives an outgassing of carbon dioxide from the ocean to the atmosphere. There has been a lack of knowledge about these complex processes, so the study is an important key to understanding the Southern Ocean’s significance for the climate and the global carbon budget,” explained study co-author Sebastiaan Swart, a professor of Oceanography at the University of Gothenburg.

In order to measure the stormy, inaccessible waters surrounding Antarctica for a long period of time, the scientists used novel robot technology, including state-of-the-art drones and ocean gliders that collected data not only from the surface of the ocean but also through to depths of one kilometer.

“This pioneering technology gave us the opportunity to collect data with long endurance, which would not have been possible via a research vessel. Thanks to these ocean robots we can now fill important knowledge gaps and gain a better understanding of the importance of the ocean for the climate,” said Professor Swart.

“This knowledge is necessary to be able to make more accurate predictions about future climate change. Currently, these environmental processes are not captured by global climate models,” added study co-author Marcel du Plessis, an expert in Physical Oceanography at the University of Gothenburg.

The study is published in the journal Nature Communications.

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By Andrei Ionescu, Earth.com Staff Writer