Science Explained/Brief

Simulations suggest Southern Ocean could flip from carbon sink to carbon source

A study published in Science Advances finds that climate simulations suggest the Southern Ocean around Antarctica may switch from an important carbon sink to a prolific source of carbon as CO2 levels are reduced.

BriefPublished 13 September 20261 min read1 linked source · 3 checked factsRevision 4

dishes of a radio telescope array at night — Illustration: National Radio Astronomy Observatory at night - panoramio · Diarrhea · CC BY 3.0 licence

Plans to limit the global temperature rise to 1.5°C above preindustrial levels depend on reaching net-zero emissions and, in many cases, actively removing CO2 from the air. A new study, published in Science Advances, finds that reducing CO2 levels may have an unexpected effect.

Climate simulations used in the study suggest the Southern Ocean around Antarctica may switch from being an important carbon sink to being a prolific source of carbon. The result comes from models rather than from observations of the ocean itself.

The work points to a possible trade-off in mitigation: cutting emissions and pulling CO2 from the air could change how the Southern Ocean exchanges carbon with the atmosphere.

What the reporting says

Each line below is stated by the page named above it, and only by that page.

Stated by phys.org

A new study, published in Science Advances, finds that reducing CO2 levels may have an unexpected effect.
Climate simulations used in the study suggest the Southern Ocean around Antarctica may switch from being an important carbon sink to being a prolific source of carbon.
Plans to limit the global temperature rise to 1.5°C above preindustrial levels depend on reaching net-zero emissions and, in many cases, actively removing CO2 from the air.

Our view

This is a model-based signal about a possible side effect of mitigation, not a confirmed real-world shift.

What the reporting says: Climate simulations used in the study suggest the Southern Ocean around Antarctica may switch from being an important carbon sink to being a prolific source of carbon.

Sources

Phys.orgPublished 13 September 2026 · checked 14 September 2026

Found through monitored feeds: Phys.org. A feed address is how the desk finds a story, not the evidence for it — the sources listed above are the pages the facts were taken from.

How this story was checked

This story was written from the 1 page listed above, all read on 14 September 2026.
Every figure and identifier in the text was required to appear in that source text before publication; any that did not was removed rather than checked by memory.
Of the 3 reported statements recorded for this story, 3 are each traceable to a linked page and are shown above. The rest were dropped.
Quantities traced to the source text: yes; identifiers traced: yes.
Where the reporting was silent, the text says so instead of filling the gap. This is a reported story, not a review of the source.

Simulations suggest Southern Ocean could flip from carbon sink to carbon source

What the reporting says

Our view

Sources

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