The formation of Antarctic Bottom Water-the cold, dense water that occupies the abyssal layer of the global ocean-is a key process in global ocean circulation. This water mass is formed as dense shelf water sinks to depth. Three regions around Antarctica where this process takes place have been previously documented. The presence of another source has been identified in hydrographic and tracer data, although the site of formation is not well constrained. Here we document the formation of dense shelf water in the Cape Darnley polynya (65°-69°E) and its subsequent transformation into bottom water using data from moorings and instrumented elephant seals (Mirounga leonina). Unlike the previously identified sources of Antarctic Bottom Water, which require the presence of an ice shelf or a large storage volume, bottom water production at the Cape Darnley polynya is driven primarily by the flux of salt released by sea-ice formation. We estimate that about 0.3-0.7 × 106 m3 s-1 of dense shelf water produced by the Cape Darnley polynya is transformed into Antarctic Bottom Water. The transformation of this water mass, which we term Cape Darnley Bottom Water, accounts for 6-13% of the circumpolar total. Copyright © 2013 Macmillan Publishers Limited.

Item Type:	Refereed Article
Keywords:	Antarctica, bottom water, Cape Darnley polynya
Research Division:	Earth Sciences
Research Group:	Oceanography
Research Field:	Physical Oceanography
Objective Division:	Environment
Objective Group:	Climate and Climate Change
Objective Field:	Climate and Climate Change not elsewhere classified
UTAS Author:	Williams, GD (Associate Professor Guy Williams)
UTAS Author:	Tamura, T (Dr Takeshi Tamura)
UTAS Author:	Herraiz Borreguero, L (Dr Laura Herraiz Borreguero)
UTAS Author:	Hindell, MA (Professor Mark Hindell)
ID Code:	84349
Year Published:	2013
Web of Science® Times Cited:	103
Deposited By:	CRC-Antarctic Climate & Ecosystems
Deposited On:	2013-05-08
Last Modified:	2017-10-31
Downloads:	0