The mass of CO₂ removed from seawater through electrochemical separation — or other approaches — can be measured directly as a metered output from the direct ocean removal (DOR) system. It can also be checked for consistency against operational data from the DOR system and characterization of the seawater effluent that is depleted of dissolved inorganic carbon (DIC). The quantity of CO₂ directly removed from seawater may not be equal to the quantity of CO₂ stored (see Leakage) or the quantity of CO₂ indirectly removed by atmospheric drawdown (see Air sea gas exchange). Direct removal of CO₂ from seawater produces DIC-depleted seawater and results in subsequent atmospheric carbon removal by inducing air-sea gas exchange. Thus, the quantity of CO₂ removed directly from seawater must be clearly quantified and validated as a separate measurement from CO₂ storage or atmospheric CO₂ drawdown.