On the warm inflow at the eastern boundary of the Weddell Gyre


Contact
svenja.ryan [ at ] awi.de

Abstract

The Weddell Sea plays an important role for the global oceans and climate by being one of the biggest production and export areas of Antarctic Bottom Water (AABW). Circumpolar Deep Water (CDW) enters the Weddell Gyre (WG) at its eastern boundary. Then called Warm Deep Water (WDW), it is a major contributor to the formation of deep and bottom waters due to ocean-ice shelf interactions in the southern and soutwestern Weddell Sea. Hydrographic data collected between 0 and 30°E on the RV Polarstern cruise ANT XX/2 reveals a two-core structure for the eastern inflow of warm water at roughly 20°E but not further downstream at the Greenwich meridian (GM). Model results and climatological fields suggest that the two cores represent two separate modes of warm inflow. One mode is driven by eddy mixing in the northeastern corner of the WG and the other one is an advective mode, forming the southern branch of the inflow which extends beyond 30°E before turning westward. Both pathways are likely to carry waters from different origins within the Antarctic Circumpolar Current (ACC), where more ventilated CDW is found at the Southern Boundary (SB) compared to the centre. The southern route shows considerable interannual variability in the model. A variable inflow of two types of CDW together with admixed recirculated and cooler waters from the Weddell Sea can potentially contribute to the observed variability and warming trend of WDW over the last decade at the GM.



Item Type
Article
Authors
Divisions
Primary Division
Programs
Primary Topic
Publication Status
Published
Eprint ID
40649
DOI 10.1016/j.dsr.2015.11.002

Cite as
Ryan, S. , Schröder, M. , Huhn, O. and Timmermann, R. (2016): On the warm inflow at the eastern boundary of the Weddell Gyre , Deep Sea Research Part I: Oceanographic Research Papers, 107 , pp. 70-81 . doi: 10.1016/j.dsr.2015.11.002


Download
[thumbnail of Ryan_at_al_2016.pdf]
Preview
PDF
Ryan_at_al_2016.pdf

Download (9MB) | Preview
Cite this document as:

Share
Add to AnyAdd to TwitterAdd to FacebookAdd to LinkedinAdd to PinterestAdd to Email


Citation

Geographical region

Research Platforms

Campaigns
ANT > XXII


Actions
Edit Item Edit Item