This post was first published in September 2023, and we corrected it on 4 October 2026 so that it matches our current reports.
Carbon dioxide is very important for the climate, because rising carbon dioxide in the air is a main driver of the warming of the planet. It is also very important for the ocean, because the sea absorbs carbon dioxide from the air, and rising carbon dioxide lowers seawater pH and carbonate ion concentration, which reduces aragonite saturation.
Cutting carbon dioxide emissions is very important for the climate and for limiting ocean acidification. It would not, on its own, remove the black carbon, persistent pollutants that dissolve in fat, and plastic that are already in the ocean, or repair any damage to the microlayer, the thin skin at the surface of the ocean, because those materials act through biogeochemical and ecotoxicological pathways that are distinct from those of carbon dioxide.
Carbon dioxide is not the only stress on marine life. An interpretive synthesis of documented declines places marine animal life at about 35 to 54% of its 1850 level, and most of that loss was recorded before acidification became a factor, so acidification, which rising carbon dioxide drives, is now acting on a system that fishing, whaling, habitat loss, pollution and climate disruption had already depleted.
Our plankton paper, a preliminary survey that was under review at the journal Ocean Science in October 2026, suggests that reducing marine pollution may protect the biological productivity of the ocean and may support ecosystem recovery in a way that complements cutting carbon dioxide emissions, although the survey itself did not test this idea.
Our reports are described on the climate change page, which links to the Research Square preprint and the EGUsphere preprint, and on 4 October 2026 neither report had completed peer review.