Langlais_etal_2017_SREPsubduction_final.pdf (7.5 MB)
Stationary Rossby waves dominate subduction of anthropogenic carbon in the Southern Ocean
journal contribution
posted on 2023-05-19, 15:02 authored by Langlais, CE, Lenton, A, Matear, R, Monselesan, D, Benoit LegresyBenoit Legresy, Eva CougnonEva Cougnon, Stephen RintoulThe Southern Ocean has taken up more than 40% of the total anthropogenic carbon (Cant) stored in the oceans since the preindustrial era, mainly in subantarctic mode and intermediate waters (SAMW-AAIW). However, the physical mechanisms responsible for the transfer of Cant into the ocean interior remain poorly understood. Here, we use high resolution (1/10°) ocean simulations to investigate these mechanisms at the SAMW-AAIW subduction hotspots. Mesoscale Stationary Rossby Waves (SRWs), generated where the Antarctic Circumpolar Current interacts with topography, make the dominant contribution to the Cant transfer in SAMW-AAIW in the Indian and Pacific sectors (66% and 95% respectively). Eddy-resolving simulations reproduce the observed Cant sequestration in these layers, while lower spatial resolution models, that do not reproduce SRWs, underestimate the inventory of Cant in these layers by 40% and overestimate the storage in denser layers. A key implication is that climate model simulations, that lack sufficient resolution to represent sequestration by SRWs, are therefore likely to overestimate the residence time of Cant in the ocean, with implications for simulated rates of climate change.
History
Publication title
Scientific ReportsVolume
7Article number
17076Number
17076Pagination
1-10ISSN
2045-2322Department/School
Institute for Marine and Antarctic StudiesPublisher
Nature Publishing GroupPlace of publication
United KingdomRights statement
Copyright 2017 The Authors. Licensed under Creative Commons Attribution 4.0 International (CC BY 4.0) https://creativecommons.org/licenses/by/4.0/Repository Status
- Open