A scientist from the University of Miami, Rosenstiel School of Marine and Atmospheric Science, will make high quality chlorofluorocarbon (CFC) and sulfur hexafluoride (SF6) measurements during the 2013 GEOTRACES cruise to the Eastern Tropical South Pacific Ocean. These measurements will provide an overall oceanographic context for the cruise, as well as contribute to the interpretation of GEOTRACES trace elements and their isotopes (TEIs) by characterizing the physical processes which can affect their speciation and internal cycling. In addition, for the low oxygen waters in the oxygen minimum zone (OMZ), the researcher will distinguish water that is old as a result of physical circulation processes from recently renewed, yet low oxygen waters due to biochemical processes. Tracer ages will help constrain the residence times of the OMZ layers. Secondly, rates of biochemically important processes such as apparent oxygen utilization and denitrification in upwelling areas, the OMZ, and low nitrate regions will be compared with estimates from historical data. Lastly, ventilated thermocline and intermediate water masses within which TEIs reside will be identified and their effective time scales of circulation from the source regions will be estimated.
In terms of the broader impacts, the scientist will continue her active participation in the National Science Foundation ADVANCE program, as well as the Mentoring Physical Oceanography Women to Increase Retention (MPOWIR) program. One graduate student will be supported and trained as part of this project.