Size matters: another reason why the Atlantic is saltier than the Pacific

Size matters: another reason why the Atlantic is saltier than the Pacific AbstractThe surface salinity in the North Atlantic controls the position of the sinking branch of the meridional overturning circulation (MOC): the North Atlantic has higher salinity, so deep water formation occurs there, rather than in the North Pacific. Here it is shown that in a 3-D primitive equation model of two basins of different widths connected by a re-entrant channel, there is a preference for sinking in the narrow basin even under zonally-uniform surface forcing. This preference is linked to the details of the velocity and salinity fields in the “sinking” basin. The southward western boundary current associated with the wind-driven subpolar gyre has higher velocity in the wide basin than in the narrow basin. It overwhelms the northward western boundary current associated with the MOC for wide-basin sinking, so fresh water is brought from the far north of the domain southward and forms a pool on the western boundary in the wide basin. The fresh pool suppresses local convection and spreads eastward, leading to low salinities in the north of the wide basin for wide-basin sinking. This pool of fresh water is much less prominent in the narrow basin for narrow-basin sinking, where the northward MOC western boundary current overcomes the southward western boundary current associated with the wind-driven subpolar gyre, bringing salty water from lower latitudes northward and enabling deep water mass formation. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Physical Oceanography American Meteorological Society

Size matters: another reason why the Atlantic is saltier than the Pacific

Loading next page...
 
/lp/ams/size-matters-another-reason-why-the-atlantic-is-saltier-than-the-tAFIrrTyXn
Publisher
American Meteorological Society
Copyright
Copyright © American Meteorological Society
ISSN
1520-0485
D.O.I.
10.1175/JPO-D-17-0075.1
Publisher site
See Article on Publisher Site

Abstract

AbstractThe surface salinity in the North Atlantic controls the position of the sinking branch of the meridional overturning circulation (MOC): the North Atlantic has higher salinity, so deep water formation occurs there, rather than in the North Pacific. Here it is shown that in a 3-D primitive equation model of two basins of different widths connected by a re-entrant channel, there is a preference for sinking in the narrow basin even under zonally-uniform surface forcing. This preference is linked to the details of the velocity and salinity fields in the “sinking” basin. The southward western boundary current associated with the wind-driven subpolar gyre has higher velocity in the wide basin than in the narrow basin. It overwhelms the northward western boundary current associated with the MOC for wide-basin sinking, so fresh water is brought from the far north of the domain southward and forms a pool on the western boundary in the wide basin. The fresh pool suppresses local convection and spreads eastward, leading to low salinities in the north of the wide basin for wide-basin sinking. This pool of fresh water is much less prominent in the narrow basin for narrow-basin sinking, where the northward MOC western boundary current overcomes the southward western boundary current associated with the wind-driven subpolar gyre, bringing salty water from lower latitudes northward and enabling deep water mass formation.

Journal

Journal of Physical OceanographyAmerican Meteorological Society

Published: Oct 4, 2017

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off