Future Changes of Carbon Chemistry Under the Implementation of Artificial Ocean Alkalinization Based on CMIP6 Simulations

Artificial ocean alkalinization (AOA) is one of the most promising marine carbon dioxide removal technologies. We applied the results from the 6th Coupled Model Intercomparison Project (CMIP6) to characterize the temporal and spatial variabilities of future marine carbon chemistry under the implementation of AOA. Our study shown the carbon system varied widely under the implement of AOA, but some efficiencies may be covered up by the forcing of high carbon emission scenario. Basing on the CMIP6 protocol, which added 0.14 Pmol alkalinity into the ocean ever year, AOA promoted the increase of DIC, delayed the rise of pCO2, and restrained the aggravation of pH and Ω, actually. The temperate oceans in both hemispheres were the most significant impacted basins, whereas the Southern Ocean were the less affected region. In the present century, the oceanic carbon sink would intensify rapidly until the year around 2080, and then weaken slowly. Implementation of AOA merely changed the relative strength of oceanic sink rather than its variation pattern. In deep ocean, what’ more, the effectiveness of AOA did exist, but was quite little for the mitigation of ocean acidification.