Dominant frazil ice production in the Cape Darnley polynya leading to Antarctic Bottom Water formation.

ABSTRACT: Antarctic Bottom Water (AABW) occupies the abyssal layer of the world ocean and contributes to the global overturning circulation. It originates from dense shelf water, which forms from brine rejection during sea ice production. An important region of AABW formation has been identified off the Cape Darnley polynya. However, it remains unclear why and how high ice production leads to AABW formation. Using moored acoustic measurements and a satellite microwave algorithm, we reveal that underwater frazil ice dominates in the polynya. This underwater ice formation prevents heat-insulating surface-cover ice forming, thereby enabling efficient ice production. The high ice production in the nearshore and longer residence times create high-salinity source water for the AABW. Underwater frazil ice

SUBMITTER: Ohshima KI 

PROVIDER: S-EPMC9581479 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature