Ocean Snow
In June 2026, researchers discovered that bacteria inside marine fish guts help precipitate calcium carbonate crystals — which drift to the seafloor as “ocean snow,” shaping global ocean alkalinity in ways carbon-cycle models never accounted for.
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CaCO₃ crystals
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seafloor deposit
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Fish gut carbon pathway · CaCO₃ cycle
Ocean Snow · cycles every 7 s
The Discovery · June 2026
A surprising study found that bacteria inside marine fish guts help precipitate calcium carbonate (CaCO₃) — and that this gut-derived carbonate may be a major, previously unaccounted source of ocean alkalinity and carbon sequestration.