The University of Southampton
University of Southampton Institutional Repository

A regional thermohaline inverse method for estimating circulation and mixing in the Arctic and subpolar North Atlantic

A regional thermohaline inverse method for estimating circulation and mixing in the Arctic and subpolar North Atlantic
A regional thermohaline inverse method for estimating circulation and mixing in the Arctic and subpolar North Atlantic
A Regional Thermohaline Inverse Method (RTHIM) is presented that estimates velocities through the section bounding an enclosed domain and transformation rates due to interior mixing within the domain, given inputs of surface boundary fluxes of heat and salt and interior distributions of salinity and temperature. The method works by invoking a volumetric balance in thermohaline coordinates between the transformation due to mixing, surface fluxes and advection, while constraining the mixing to be down tracer gradients. The method is validated using a 20-year mean of outputs from the NEMO model in an Arctic and subpolar North Atlantic domain, bound to the south by a section with a mean latitude of 66°N. RTHIM solutions agree well with the NEMO model ‘truth’ and are robust to a range of parameters; the MOC, heat and freshwater transports calculated from an ensemble of RTHIM solutions are within 12%, 10% and 19%, respectively, of the NEMO values. There is also bulk agreement between RTHIM solution transformation rates due to mixing and those diagnosed from NEMO. Localized differences in diagnosed mixing may be used to guide the development of mixing parameterizations in models such as NEMO, whose downgradient diffusive closures with prescribed diffusivity may be considered oversimplified and too restrictive.
0739-0572
Mackay, Neill
04a0ec32-fec9-4876-a0c3-509177721555
Wilson, Chris
fadc83b7-f240-485b-8734-51099d02775a
Zika, Jan
1843cce7-77ce-4ef6-9f79-bcf4f9db30e5
Holliday, N. Penny
c4ef99c7-1be1-4148-ae23-0c678aa4f8f2
Mackay, Neill
04a0ec32-fec9-4876-a0c3-509177721555
Wilson, Chris
fadc83b7-f240-485b-8734-51099d02775a
Zika, Jan
1843cce7-77ce-4ef6-9f79-bcf4f9db30e5
Holliday, N. Penny
c4ef99c7-1be1-4148-ae23-0c678aa4f8f2

Mackay, Neill, Wilson, Chris, Zika, Jan and Holliday, N. Penny (2018) A regional thermohaline inverse method for estimating circulation and mixing in the Arctic and subpolar North Atlantic. Journal of Atmospheric and Oceanic Technology. (doi:10.1175/JTECH-D-17-0198.1).

Record type: Article

Abstract

A Regional Thermohaline Inverse Method (RTHIM) is presented that estimates velocities through the section bounding an enclosed domain and transformation rates due to interior mixing within the domain, given inputs of surface boundary fluxes of heat and salt and interior distributions of salinity and temperature. The method works by invoking a volumetric balance in thermohaline coordinates between the transformation due to mixing, surface fluxes and advection, while constraining the mixing to be down tracer gradients. The method is validated using a 20-year mean of outputs from the NEMO model in an Arctic and subpolar North Atlantic domain, bound to the south by a section with a mean latitude of 66°N. RTHIM solutions agree well with the NEMO model ‘truth’ and are robust to a range of parameters; the MOC, heat and freshwater transports calculated from an ensemble of RTHIM solutions are within 12%, 10% and 19%, respectively, of the NEMO values. There is also bulk agreement between RTHIM solution transformation rates due to mixing and those diagnosed from NEMO. Localized differences in diagnosed mixing may be used to guide the development of mixing parameterizations in models such as NEMO, whose downgradient diffusive closures with prescribed diffusivity may be considered oversimplified and too restrictive.

Text
jtech-d-17-0198.1 - Accepted Manuscript
Download (3MB)

More information

Submitted date: 17 November 2017
Accepted/In Press date: 10 March 2018
e-pub ahead of print date: 10 December 2018
Published date: December 2018

Identifiers

Local EPrints ID: 422777
URI: http://eprints.soton.ac.uk/id/eprint/422777
ISSN: 0739-0572
PURE UUID: bad22ffc-16a5-4d54-b659-6ab3e1061221

Catalogue record

Date deposited: 03 Aug 2018 16:31
Last modified: 27 Jan 2022 17:50

Export record

Altmetrics

Contributors

Author: Neill Mackay
Author: Chris Wilson
Author: Jan Zika
Author: N. Penny Holliday

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×