HR: 08:00h
AN: OS11C-01 INVITED     [Abstracts]
TI: Application of helium isotopes to studies of ocean circulation
AU: * Schlosser, P
EM: schlosser@ldeo.columbia.edu
AF: Columbia University Lamont-Doherty Earth Observatory, 61 Route 9W, Palisades, NY 10964 United States
AU: Newton, R
EM: rnewton@ldeo.columbia.edu
AF: Columbia University Lamont-Doherty Earth Observatory, 61 Route 9W, Palisades, NY 10964 United States
AU: Winckler, G
AF: Columbia University Lamont-Doherty Earth Observatory, 61 Route 9W, Palisades, NY 10964 United States
AU: Lupton, J
AF: NOAA PMEL Hatfield Marine Science Center, 2115 S.E. OSU Dr., Newport, OR 97365 United States
AU: Jenkins, W
AF: Woods Hole Oceanographic Institution, Mail Stop No. 25, Woods Hole, MA 02543 United States
AU: Top, Z
AF: University of Miami RSMAS, 4600 Rickenbacker Causeway, Miami, 33149 United States
AU: Roether, W
AF: University of Bremen, Postfach 33 04 40 Kusteiner Strasse Bremen, Bremen, 28359 Germany
AU: Jean-Baptiste, P
AF: Saclay, Centre d'Etudes de Saclay, Gif Sur Yvette, 91191 France
AB: Since the discovery of excess He-3 in the ocean by Clarke and Craig in the 1960's helium isotopes have been used in local, regional and global studies of circulation patterns and water mass transformation in the world ocean. From initial pilot studies through systematic exploration of these tracers during the GEOSECS (Geochemical Ocean Sections) program to the recent global survey as part of the WOCE (World Ocean Circulation Experiment) hydrographic program (WHP) we obtained more detailed information on the distribution of helium isotopes, as well as their sources and sinks in the ocean. This information can now be applied to construct global fields of helium isotopes and to extract unique information on the circulation patterns at different depth levels in the ocean, as well as on local and regional processes such as ventilation of water masses in deep water formation regions. Additionally, the data sets are now sufficiently large to be useful for validation of Ocean General Circulation Models (OGCM's). In this contribution we present examples of global helium isotope fields constructed from major programs such as GEOCECS, TTO (Transient Tracers in the Ocean), SAVE (South Atlantic Ventilation Experiment) and WOCE, as well as from individual ocean sections. We use the data to delineate circulation patterns in the major ocean basins at several depth levels, especially mid-depth waters. Additionally, we outline the use of helium isotopes in studies of ocean ventilation. Finally, we compare observed and simulated helium isotope fields to highlight OGCM capabilities and deficiencies to reproduce internal He-3 excesses in the ocean and the related ventilation processes.
DE: 4820 Gases
DE: 4283 Water masses
DE: 4532 General circulation
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting