New early winter fCO2 data reveal continuous uptake of CO2 by the Weddell Sea

M. H. C. Stoll; H. J. W. De Baar; M. Hoppema; E. Fahrbach

doi:10.3402/tellusb.v51i3.16460

New early winter fCO2 data reveal continuous uptake of CO2 by the Weddell Sea

Tellus B: Chemical and Physical Meteorology

Volume 51 (1999): Issue 3

By: M. H. C. Stoll, H. J. W. De Baar, M. Hoppema and E. Fahrbach

Open Access

|Jan 1999

Abstract

The Antarctic Ocean has been thought to be unimportant for the uptake of CO₂ since upwelling of CO₂-enriched deep waters would favour outgassing. Here we present the first direct fCO₂ measurements obtained in early winter under the ice which, combined with estimated entrainment rates, show that the Weddell Sea, an area of intense upwelling manifested by the doming structure of the cyclonic gyre, has the capability to be almost continuously a sink for atmospheric CO₂. A flux, effective after the ice cover disappears, is estimated to be — 0.74 ± 0.7 mmol/m^-2 d^-1. Combined with a flux estimate in late autumn (- 2.0 mmol m^-2 d^-1) integrated over the area of the central Weddell Gyre, a carbon uptake of 0.24 × 10¹³ gC y^-1 (≈ 2.4× 10^-3 GtC y^-1 being ≈ 1‰ of global uptake) is computed, which is about a third of the strength of the biological pump of the Weddell Sea.

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DOI: https://doi.org/10.3402/tellusb.v51i3.16460 | Journal eISSN: 1600-0889

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Language: English

Page range: 679 - 687

Submitted on: Jan 21, 1998

Accepted on: Aug 15, 1998

Published on: Jan 1, 1999

Published by: Stockholm University Press

In partnership with: Paradigm Publishing Services

© 1999 M. H. C. Stoll, H. J. W. De Baar, M. Hoppema, E. Fahrbach, published by Stockholm University Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 51 (1999): Issue 3