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This content will become publicly available on December 1, 2026

Title: Seasonal regimes of warm Circumpolar Deep Water intrusion toward Antarctic ice shelves
Abstract Basal melting of Antarctic ice shelves is primarily driven by heat delivery from warm Circumpolar Deep Water. Here we classify near-shelf water masses in an eddy-resolving numerical model of the Southern Ocean to develop a unified view of warm water intrusion onto the Antarctic continental shelf. We identify four regimes on seasonal timescales. In regime 1 (East Antarctica), heat intrusions are driven by easterly winds via Ekman dynamics. In regime 2 (West Antarctica), intrusion is primarily determined by the strength of a shelf-break undercurrent. In regime 3, the warm water cycle on the shelf is in antiphase with dense shelf water production (Adélie Coast). Finally, in regime 4 (Weddell and Ross seas), shelf-ward warm water inflow occurs along the western edge of canyons during periods of dense shelf water outflow. Our results advocate for a reformulation of the traditional annual-mean regime classification of the Antarctic continental shelf.  more » « less
Award ID(s):
1936222 2332379
PAR ID:
10613925
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Springer Nature
Date Published:
Journal Name:
Communications Earth & Environment
Volume:
6
Issue:
1
ISSN:
2662-4435
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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