Symmetric Instability Ventilates Low-Oxygen Bottom Water at a bottom-attached front

Montag 12.05.2025, 11:00 → 12:00 Europe/Berlin

5-1.214 - Linke Seite – Großer, unterteilbarer Konferenzraum (GEOMAR - Standort Ostufer / GEOMAR - East Shore)

Speaker: Mareike Körner, Oregon State University, USA

Hybrid  -  online via https://geomar.webex.com/geomar-en/j.php?MTID=mf415834ed76a742bacf01eada863885d

Meeting number: 2787 635 2083
Password: XYwu583sQtA

Abstract
Submesoscale processes, including instability processes, play a key role in the oceanic energy cycle and influence material transport, shaping marine ecosystems. In this study, for the first time, we document symmetric instabilities (SI) spanning the entire water column, directly linking surface and bottom boundary layer dynamics at the Mississippi–Atchafalaya River plume. We observe that SI persists for about 40 hours after active wind forcing ceases. During this phase, vertical advective transport by SI exceeds turbulent mixing by an order of magnitude. These strong vertical motions ventilate low-oxygen bottom waters and transport heat downward. Our results show that SI facilitates vertical exchange, even in the absence of direct wind forcing, with potential implications for heat and oxygen budgets in coastal systems.