Enhanced Ventilation in Energetic Regions of the Antarctic Circumpolar Current
Abstract
Flow-topography interactions along the path of the Antarctic Circumpolar Current generate standing meanders, create regions of enhanced eddy kinetic energy (EKE), and modify frontal structure. We consider the impact of standing meanders on ventilation based on oxygen measurements from Argo floats and the patterns of apparent oxygen utilization (AOU). Regions of high-EKE have relatively reduced AOU values at depths 200–700 m below the base of the mixed layer and larger AOU variance, suggesting enhanced ventilation due to both along-isopycnal stirring and enhanced exchange across the base of the mixed layer. Vertical exchange is inferred from finite-size Lyapunov exponents, a proxy for the magnitude of surface lateral density gradients, which suggest that submesoscale vertical velocities may contribute to ventilation. The shaping of ventilation by standing meanders has implications for the temporal and spatial variability of air‒sea exchange.
Additional Information
© 2022. American Geophysical Union. Issue Online: 06 July 2022. Version of Record online: 06 July 2022. Accepted manuscript online: 25 June 2022. Manuscript accepted: 16 June 2022. Manuscript revised: 13 June 2022. Manuscript received: 22 December 2021. L. A. Dove and A. F. Thompson acknowledge funding from National Science Foundation (NSF) award OCE-1756956, the David and Lucille Packard Foundation, and the Resnick Sustainability Institute. L. A. Dove was additionally supported by an NSF Graduate Research Fellowship. D. Balwada and A. R. Gray were supported by NSF Award OCE-1756882. A. R. Gray acknowledges additional funding through National Oceanic and Atmospheric Administration Award NA20OAR4320271 and through NSF's Southern Ocean Carbon and Climate Observations and Modeling Project under Awards PLR-1425989 and OPP-1936222. The authors are grateful for the comments of three anonymous reviewers, which led to the improvement of this manuscript. Data Availability Statement. The float data were collected and made freely available by the International Argo Program and the national programs that contribute to it (https://argo.ucsd.edu, https://www.ocean-ops.org). The Argo Program is part of the Global Ocean Observing System. The float profiles used in this manuscript are available in the Argo Global Data Assembly Center 10 June 2021 screenshot (https://doi.org/10.17882/42182%2385023). Sea level anomaly products were produced and distributed by the Copernicus Marine 360 and Environment Monitoring Service and are available at https://resources.marine.copernicus.eu/product-detail/SEALEVEL_GLO_PHY_L4_MY_008_047/INFORMATION. Finite-size Lyapunov Exponents were produced and distributed by AVISO+ and are available at https://www.aviso.altimetry.fr/en/data/products/value-added-products/fsle-finite-size-lyapunov-exponents.htmlAttached Files
Published - 2021GL097574.pdf
Accepted Version - 2021GL097574-acc.pdf
Supplemental Material - 2021gl097574-sup-0001-supporting_information_si-s01.pdf
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Additional details
- Eprint ID
- 115648
- Resolver ID
- CaltechAUTHORS:20220715-744273000
- OCE-1756956
- NSF
- David and Lucile Packard Foundation
- Resnick Sustainability Institute
- NSF Graduate Research Fellowship
- OCE-1756882
- NSF
- NA20OAR4320271
- National Oceanic and Atmospheric Administration (NOAA)
- PLR-1425989
- NSF
- OPP-1936222
- NSF
- Created
-
2022-07-20Created from EPrint's datestamp field
- Updated
-
2023-10-06Created from EPrint's last_modified field
- Caltech groups
- Resnick Sustainability Institute, Division of Geological and Planetary Sciences