Abstract
Seasonal and interannual variability in the Southern Ocean carbonate system is investigated using output from a historically forced (1948–2007) ocean general circulation model with embedded biogeochemistry. Atmospheric CO2 is fixed at preindustrial levels to investigate carbonate system variability in the absence of an anthropogenic CO2 perturbation. It is found that nearly a quarter of interannual variability in Southern Ocean Pacific sector surface carbonate ion concentration