The University of Southampton
University of Southampton Institutional Repository

Extreme air–sea interaction over the North Atlantic subpolar gyre during the winter of 2013–2014 and its sub-surface legacy

Extreme air–sea interaction over the North Atlantic subpolar gyre during the winter of 2013–2014 and its sub-surface legacy
Extreme air–sea interaction over the North Atlantic subpolar gyre during the winter of 2013–2014 and its sub-surface legacy
Exceptionally low North American temperatures and record-breaking precipitation over the British Isles during winter 2013–2014 were interconnected by anomalous ocean evaporation over the North Atlantic subpolar gyre region (SPG). This evaporation (or oceanic latent heat release) was accompanied by strong sensible heat loss to the atmosphere. The enhanced heat loss over the SPG was caused by a combination of surface westerly winds from the North American continent and northerly winds from the Nordic Seas region that were colder, drier and stronger than normal. A distinctive feature of the air–sea exchange was that the enhanced heat loss spanned the entire width of the SPG, with evaporation anomalies intensifying in the east while sensible heat flux anomalies were slightly stronger upstream in the west. The immediate impact of the strong air–sea fluxes on the ocean–atmosphere system included a reduction in ocean heat content of the SPG and a shift in basin-scale pathways of ocean heat and atmospheric freshwater transport. Atmospheric reanalysis data and the EN4 ocean data set indicate that a longer-term legacy of the winter has been the enhanced formation of a particularly dense mode of Subpolar Mode Water (SPMW)—one of the precursors of North Atlantic Deep Water and thus an important component of the Atlantic Meridional Overturning Circulation. Using particle trajectory analysis, the likely dispersal of newly-formed SPMW is evaluated, providing evidence for the re-emergence of anomalously cold SPMW in early winter 2014/2015.
North Atlantic Ocean, Air–sea fluxes, Ocean heat content, Subpolar Mode Water, Winter 2013–2014
0930-7575
4027-4045
Grist, J.P.
ffea99af-f811-436f-9bac-5b02ba6dc00f
Josey, S.A.
2252ab7f-5cd2-49fd-a951-aece44553d93
Jacobs, Z.L.
f40f8278-6f3f-4394-b18a-442bd130a958
Marsh, R.
702c2e7e-ac19-4019-abd9-a8614ab27717
Sinha, B.
544b5a07-3d74-464b-9470-a68c69bd722e
Van Sebille, E.
6f4c4ae1-9816-401d-8565-9fa4df735100
Grist, J.P.
ffea99af-f811-436f-9bac-5b02ba6dc00f
Josey, S.A.
2252ab7f-5cd2-49fd-a951-aece44553d93
Jacobs, Z.L.
f40f8278-6f3f-4394-b18a-442bd130a958
Marsh, R.
702c2e7e-ac19-4019-abd9-a8614ab27717
Sinha, B.
544b5a07-3d74-464b-9470-a68c69bd722e
Van Sebille, E.
6f4c4ae1-9816-401d-8565-9fa4df735100

Grist, J.P., Josey, S.A., Jacobs, Z.L., Marsh, R., Sinha, B. and Van Sebille, E. (2016) Extreme air–sea interaction over the North Atlantic subpolar gyre during the winter of 2013–2014 and its sub-surface legacy. Climate Dynamics, 46 (11), 4027-4045. (doi:10.1007/s00382-015-2819-3).

Record type: Article

Abstract

Exceptionally low North American temperatures and record-breaking precipitation over the British Isles during winter 2013–2014 were interconnected by anomalous ocean evaporation over the North Atlantic subpolar gyre region (SPG). This evaporation (or oceanic latent heat release) was accompanied by strong sensible heat loss to the atmosphere. The enhanced heat loss over the SPG was caused by a combination of surface westerly winds from the North American continent and northerly winds from the Nordic Seas region that were colder, drier and stronger than normal. A distinctive feature of the air–sea exchange was that the enhanced heat loss spanned the entire width of the SPG, with evaporation anomalies intensifying in the east while sensible heat flux anomalies were slightly stronger upstream in the west. The immediate impact of the strong air–sea fluxes on the ocean–atmosphere system included a reduction in ocean heat content of the SPG and a shift in basin-scale pathways of ocean heat and atmospheric freshwater transport. Atmospheric reanalysis data and the EN4 ocean data set indicate that a longer-term legacy of the winter has been the enhanced formation of a particularly dense mode of Subpolar Mode Water (SPMW)—one of the precursors of North Atlantic Deep Water and thus an important component of the Atlantic Meridional Overturning Circulation. Using particle trajectory analysis, the likely dispersal of newly-formed SPMW is evaluated, providing evidence for the re-emergence of anomalously cold SPMW in early winter 2014/2015.

Text
NAwinterpaper_RESUB_final6.pdf - Accepted Manuscript
Download (298kB)

More information

Accepted/In Press date: September 2015
e-pub ahead of print date: 5 September 2015
Published date: June 2016
Keywords: North Atlantic Ocean, Air–sea fluxes, Ocean heat content, Subpolar Mode Water, Winter 2013–2014
Organisations: Marine Systems Modelling, Physical Oceanography, Marine Physics and Ocean Climate

Identifiers

Local EPrints ID: 380994
URI: http://eprints.soton.ac.uk/id/eprint/380994
ISSN: 0930-7575
PURE UUID: a60d1404-2fee-41a0-bb9b-04f0bdc3ae18

Catalogue record

Date deposited: 29 Oct 2015 13:28
Last modified: 17 Dec 2019 06:56

Export record

Altmetrics

Contributors

Author: J.P. Grist
Author: S.A. Josey
Author: Z.L. Jacobs
Author: R. Marsh
Author: B. Sinha
Author: E. Van Sebille

University divisions

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.

×