The potential impact of the uncertainty on final estimates of net carbon removal or storage duration: negligible, low, medium, high, or very high.
Interventions like adding alkalinity or removing CO₂ shift the pH and carbonate ion concentration of seawater, and could cause abiotic precipitation of calcium carbonate (CaCO₃) or brucite (Mg(OH)₂). This is important to characterize as this precipitation results in CO₂ outgassing. It remains to be determined what specific combination of suitable nucleation conditions and supersaturation of CaCO₃ is needed to cause significant precipitation. Abiotic precipitation can be minimized by controlling the dilution and dispersal on alkalinity-enhanced or DIC-depleted water.
Updated component to reflect that abiotic precipitation of brucite (in addition to calcite) impacts CO₂ outgassing, and edited for cross-pathway consistency. For the Mineral OAE version of this component, updated to reflect the differentiation between different types of mineral additions. These edits are described further here.
Sep 19 2022
First release.
Secondary precipitation
Uncertainty
The potential impact of the uncertainty on final estimates of net carbon removal or storage duration: negligible, low, medium, high, or very high.
Interventions like adding alkalinity or removing CO₂ shift the pH and carbonate ion concentration of seawater, and could cause abiotic precipitation of calcium carbonate (CaCO₃) or brucite (Mg(OH)₂). This is important to characterize as this precipitation results in CO₂ outgassing. It remains to be determined what specific combination of suitable nucleation conditions and supersaturation of CaCO₃ is needed to cause significant precipitation. Abiotic precipitation can be minimized by controlling the dilution and dispersal on alkalinity-enhanced or DIC-depleted water.
Updated component to reflect that abiotic precipitation of brucite (in addition to calcite) impacts CO₂ outgassing, and edited for cross-pathway consistency. For the Mineral OAE version of this component, updated to reflect the differentiation between different types of mineral additions. These edits are described further here.