Tracer signals of the intermediate layer of the Arabian Sea.

Rhein, Monika, Stramma, Lothar and Plähn, Olaf (1997) Tracer signals of the intermediate layer of the Arabian Sea. Open Access Geophysical Research Letters, 24 (21). pp. 2561-2564. DOI 10.1029/97GL01041.

[thumbnail of grl10138.pdf] Text
grl10138.pdf - Published Version

Download (519kB)

Supplementary data:

Abstract

In 1995, hydrographic and chlorofluorocarbon (CFCs, components F11, F12) measurements were carried out in the Gulf of Aden, in the Gulf of Oman, and in the Arabian Sea. In the Gulf of Oman, the F12 concentrations in the Persian Gulf outflow (PGW) at about 300m depth were significantly higher than in ambient surface water with saturations reaching 270%. These high values could not be caused by air-sea gas exchange. The outflow was probably contaminated with oil, and the lipophilic character of the CFCs could then lead to the observed supersaturations. The intermediate F12 maximum decreased rapidly further east and south. At the Strait of Bab el Mandeb in the Gulf of Aden, the Red Sea outflow (RSW) was saturated with F12 to about 65% at 400m depth, and decreased to 50% while descending to 800m depth. The low saturation is not surprising, because the outflow contains deep and intermediate water masses from the Red Sea which were isolated from the surface for some time. The tracer contributions to the Arabian Sea for Indian Central Water (ICW) and PGW are about equal, while below 500m depth the RSW contribution greatly exceeds ICW. Modeling the CFC budget of the Arabian Sea, the inflow of ICW north of 12 degrees N is estimated to be 1-6 Sv, depending mainly on the strength of the flow of Red Sea Water into the Arabian Sea.

Document Type: Article
Keywords: Tracer signals, intermediate layer, Arabian Sea; R.V. Meteor; R.V. Sonne; M32; SO89
Research affiliation: OceanRep > GEOMAR > FB1 Ocean Circulation and Climate Dynamics > FB1-PO Physical Oceanography
Refereed: Yes
Open Access Journal?: No
Publisher: AGU (American Geophysical Union)
Expeditions/Models/Experiments:
Date Deposited: 19 Apr 2016 10:27
Last Modified: 13 Feb 2018 12:54
URI: https://oceanrep.geomar.de/id/eprint/32106

Actions (login required)

View Item View Item