The Sensitivity of the Marine Carbonate System to Regional Ocean Alkalinity Enhancement

Ocean Alkalinity Enhancement (OAE) simultaneously mitigates atmospheric concentrations of CO 2 and ocean acidification; however, no previous studies have investigated the response non-linear marine carbonate system sensitivity to alkalinity enhancement on regional scales. We hypothesise that implementations OAE can sequester more than a global implementation. To address this, we investigate physical regimes as drivers carbon-uptake potential different simulations OAE. In this idealised ocean-only set-up, total is enhanced at rate 0.25 Pmol -1 in 75-year using Max Planck Institute Model coupled HAMburg Carbon Cycle model with pre-industrial forcing. globally eight regions: Subpolar Subtropical Atlantic Pacific gyres, Indian Southern Ocean. This study reveals has capacity exceed carbon uptake by find 82–175 Pg sequestered into when regionally 156 PgC globally, compared background-state. The application most efficient, sequestering 12% Global experiment despite being applied across surface area 40 times smaller. For first time, potentials are driven pattern redistributed areas efficiencies. also show that, while becomes less sensitive all experiments responses vary depending upon background dissolved inorganic alkalinity. Furthermore, North displays previously unexpected increase high concentrations.