Can ocean deoxygenation accelerate global warming via enhanced marine N2O production?

Ocean warming is projected to cause marine deoxygenation, reduce solubility, affect ocean circulation and enhance metabolic rates over this century. These changes, affecting oceanic N2O production and emissions, have been suggested to potentially rise atmospheric N2O concentrations and increase the positive feedback to anthropogenic climate change. However, current global model projections all suggest a decline in marine N2O emissions under global warming but the processes leading to this decline are poorly constrained. Here, using an Earth system model of intermediate complexity, we disentangle the contribution of ocean deoxygenation and the direct and indirect warming effects on oceanic N2O production and emissions changes under RCP8. 5 emission scenario. We find that ocean deoxygenation and warming-reduced N2O solubility do in fact increase oceanic N2O emissions, however this ...