Ocean Chemistry and the Carbonate System
Ocean chemistry explains how seawater functions as a chemically active planetary system connecting climate, carbon storage, marine life, sediments, air-sea exchange, and long-term habitability. This article examines seawater composition, major ions, dissolved inorganic carbon, alkalinity, pH, pCO₂, carbonate equilibria, calcium carbonate saturation, ocean acidification, biological calcification, nutrients, oxygen, trace metals, sediments, carbon burial, and ocean monitoring. It shows how the carbonate system buffers atmospheric carbon dioxide while changing seawater chemistry, reducing carbonate ion availability, lowering pH, and affecting calcifying organisms, reefs, shellfish, sediments, and marine ecosystems. By linking carbonate equilibria, alkalinity, saturation state, air-sea flux, Revelle-factor intuition, and reproducible computational workflows, ocean chemistry becomes central to climate regulation and Earth-system habitability.








