Antarctic Bottom Water (AABW)
D1. Physical and chemical oceanography and marine meteorologyDefinition
Dense, cold water mass formed around Antarctica that fills the deep global ocean.
Antarctic Bottom Water is the densest water mass in the open ocean, formed mainly on the Weddell and Ross Sea shelves when brine rejection during sea-ice growth makes near-freezing water dense enough to sink. It spreads northward along the seafloor beneath NADW, ventilating the deep Pacific, Indian, and Atlantic basins. AABW formation rates are a sensitive indicator of Southern Ocean climate change.