131899 - Change in dense shelf water and Adelie land bottom water precipitated by iceberg calving.pdf (2.37 MB)
Change in dense shelf water and Adelie land bottom water precipitated by iceberg calving
journal contribution
posted on 2023-05-20, 02:43 authored by Snow, K, Stephen Rintoul, Sloyan, BM, Hogg, AMCAntarctic Bottom Water supplies the deep limb of the global overturning circulation and ventilates the abyssal ocean. Antarctic Bottom Water has warmed, freshened, and contracted in recent decades, but the causes remain poorly understood. We use unique multiyear observations from the continental shelf and deep ocean near the Mertz Polynya to examine the sensitivity of this bottom water formation region to changes on the continental shelf, including the calving of a large iceberg. Postcalving, the seasonal cycle of Dense Shelf Water (DSW) density almost halved in amplitude and the volume of DSW available for export reduced. In the deep ocean, the density and volume of Adelie Land Bottom Water decreased sharply after calving, while oxygen concentrations remained high, indicating continued ventilation by DSW. This natural experiment illustrates how local changes in forcing over the Antarctic continental shelf can drive large and rapid changes in the abyssal ocean.
History
Publication title
Geophysical Research LettersVolume
45Issue
5Pagination
2380-2387ISSN
0094-8276Department/School
Institute for Marine and Antarctic StudiesPublisher
Amer Geophysical UnionPlace of publication
2000 Florida Ave Nw, Washington, USA, Dc, 20009Rights statement
© 2018 Commonwealth of Australia Journal © American Geophysical UnionRepository Status
- Open