The University of Southampton
University of Southampton Institutional Repository

Methane dynamics in the Weddell Sea determined via stable isotope ratios and CFC-11

Heeschen, K.U., Keir, R.S., Rehder, G., Klatt, O. and Suess, E. (2004) Methane dynamics in the Weddell Sea determined via stable isotope ratios and CFC-11 Global Biogeochemical Cycles, 18, (2), pp. 1-18. (doi:10.1029/2003GB002151).

Record type: Article


The physical, chemical/biological processes that control the methane dynamics in the Weddell Sea are revealed by the distributions of methane (CH4), its stable carbon isotope ratio, ?13C-CH4, and the conservative transient tracer, chlorofluorocarbon-11 (CFC-11, CCl3F). In general, a nearly linear correlation between CH4 and CFC-11 concentrations was observed. Air-sea exchange is the major source of methane to this region, and the distribution of methane is controlled mainly by mixing between surface water and methane-poor Warm Deep Water. A significant influence of methane oxidation over the predominant two end-member mixing was only found in the Weddell Sea Bottom Water (WSBW) of the deep central Weddell Basin, where the turnover time of methane appears to be about 20 years. Mixing also controls most of the ?13C-CH4 distribution, but lighter than expected carbon isotopic ratios occur in the deep WSBW of the basin. From box model simulations, it appears that this “anomaly” is due to methane oxidation with a low kinetic isotope fractionation of about 1.004. The surface waters in the Weddell Sea and the Antarctic Circumpolar Current showed a general methane undersaturation of 6 to 25% with respect to the atmospheric mixing ratio. From this undersaturation and model-derived air-sea exchange rates, we estimate a net uptake of CH4 of roughly ?0.5 ?mol m?2 d?1 during austral autumn.

Full text not available from this repository.

More information

Published date: 2004
Keywords: chlorofluorocarbon, methane, weddell sea


Local EPrints ID: 40549
ISSN: 0886-6236
PURE UUID: 132541b3-5a15-43f3-8018-da5efb6636e0

Catalogue record

Date deposited: 04 Jul 2006
Last modified: 17 Jul 2017 15:34

Export record



Author: K.U. Heeschen
Author: R.S. Keir
Author: G. Rehder
Author: O. Klatt
Author: E. Suess

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 supports OAI 2.0 with a base URL of

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.