DOES AN OCEAN SWALLOW OR BELCH CARBON DIOXIDE?

For some time, scientists have understood that the Southern Ocean-the waters surrounding Antarctica-has been absorbing carbon dioxide from the atmosphere. In effect, such swallowing of greenhouse gas has been seen to be in mitigation of assumed "global warming". However, a recent article reports that some portions of the Southern Ocean actually are releasing carbon dioxide into the atmosphere, particularly in the winter.*

The "ups and downs" of carbon in this ocean appear to be a consequence of the pattern of currents. Some currents are said to suck down surface water bearing CO2. Other currents appear to be bringing deep water bearing decayed organic material to the surface.

According to the article, the carbon rollercoaster is not uniform. Some areas of the Southern Ocean absorb carbon dioxide, while others release it. The task at hand for scientists, therefore, is to determine whether one way or the other is more prevalent. Recent studies now suggest it may be 50-50, with the ocean releasing as much carbon dioxide as it absorbs. More research is needed not only of "current" impacts but also of the likely future, particularly if Antarctic ice melting persists.

Interestingly, this question appears to involve all aspects of the Earth. Carbon dioxide originates from activities on land; it escapes to the atmosphere; and it is absorbed in ocean waters. Searching for answers in Science can be daunting.

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*Witze,"Southern Ocean-Climate Friend or Foe",
Science News, June 8, 2019, p.24

© 2019 Daniel J. Kucera