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| Titel |
Upwelling in the Atlantic sector of the Southern Ocean inferred from helium isotope disequilibrium |
| VerfasserIn |
A. Buß, O. Huhn, J. Sültenfuss, M. Rhein |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250060792
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| Zusammenfassung |
| Upwelling plays an important role regarding the physical and biogeochemical characteristics
of the mixed layer, and it may also counteract the uptake of atmospheric gases like CO2.
However, estimates of upwelling velocities are rare, particularly in the Southern Ocean. Since
upwelling velocities are too small to be measured directly - in the order of a few meters per
day - an indirect method to infer upwelling velocities from the helium isotope disequilibrium
in the mixed layer is applied here instead. The main source of 3He to the ocean is
hydrothermal venting and thus a significant excess of 3He in the mixed layer can only be
maintained by vertical motion.
Helium isotope data - measured from 1986 to 2009 - in the Antarctic Circumpolar Current
(ACC) and the Weddell Sea shows a significant excess of 3He in the mixed layer from which
upwelling velocities will be inferred. Here, first results of upwelling estimates inferred from
helium isotope disequilibria in the ACC and the Weddell Sea will be presented. |
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