How does seawater buffer or neutralize acids created by scrubbing?

Relevant chemistry

The carbonate system - in an aqueous solution, carbonate, bicarbonate, carbon dioxide, and carbonic acid exist together in a dynamic equilibrium

When calcium carbonate (solid) reacts with water in presence of free hydrogen ions, the solid calcium carbonate dissolves forming free calcium (Ca+2) ions and free bicarbonate ions (HCO3-), hence consuming free hydrogen ions, decreasing hydrogen ion activity, and by definition increasing pH (becoming more basic) i.e. calcium carbonate acts to neutralise or buffer the solution by consuming hydrogen ions [8].

Similarly calcium and magnesium bicarbonates, which are present in seawater at a concentration of approximately 140 mg/1 [11] consume free hydrogen ions, decreasing hydrogen ion activity, and again by definition increase pH (become more basic) i.e. the bicarbonates in seawater act to neutralise or buffer the solution by consuming hydrogen ions and the carbonate system equilibrium is moved to the left.