Scientific sampling event log in the CoFeMUG cruise from R/V Knorr KN192-05 in the South Atlantic subtropical gyre and Benguela upwelling region (CoFeMUG project)

Website: https://www.bco-dmo.org/dataset/3096
Data Type: Cruise Results
Version: 2
Version Date: 2009-09-23

Project
» Cobalt, Iron and Micro-organisms from the Upwelling zone to the Gyre (CoFeMUG)

Programs
» Ocean Carbon and Biogeochemistry (OCB)
» U.S. GEOTRACES (U.S. GEOTRACES)
ContributorsAffiliationRole
Saito, Mak A.Woods Hole Oceanographic Institution (WHOI)Chief Scientist
Chandler, Cynthia L.Woods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager

Abstract
Scientific sampling event log in the CoFeMUG cruise from R/V Knorr KN192-05 in the South Atlantic subtropical gyre and Benguela upwelling region.


Coverage

Spatial Extent: N:-11 E:14.671 S:-25.004 W:-30
Temporal Extent: 2007-11-18 - 2007-12-11

Dataset Description

Scientific sampling event log.


Acquisition Description

Shipboard sampling events were logged in two separate Excel spreadsheets, one for the CTD/Niskin bottle rosette package and a second for the Trace Metal (TM) rosette package.


Processing Description

data version 1: 2009-03-28
data version 2: 2009-09-23
* Separate event logs were combined by the BCO-DMO to form one data file for the cruise.
* Modifications to original event log made after consultation with Chief Scientist and review of Deck Operations Log:

BCO-DMO retrieved missing data as needed from the original deck operations bridge log.
Station 13 cast 23 longitude taken from the navigation track data.
Station 6 TMR cast 11: event 11230908 start date changed from 11/22 to 11/23 and start time entered as 0900 GMT.


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Parameters

ParameterDescriptionUnits
eventevent number dimensionless
Cruise_IDcruise iedntifier dimensionless
stastation number; generally sequential; a number designating a general geographic location at which one or more sampling activities may occur dimensionless
castcast number dimensionless
datestart date of event (GMT) dimensionless
yearyear of start date of event (GMT) dimensionless
monmonth of year; numeric 1 to 12 dimensionless
dayday of month sampling began (GMT); numeric 1 to 31 dimensionless
timetime of day sampling began; reported in GMT as HHMM (hours and minutes) dimensionless
time_Ltime of day sampling began; reported in local time as HHMM (hours and minutes) adjusted for local time zone dimensionless
TZtimezone; the number of hours added to GMT to convert to local time (opposite of GLOBEC convention) dimensionless
lon_360longitude, from 0 to 360 decimal degrees decimal degrees
lonlongitude, in decimal degrees, East is positive, negative denotes West decimal degrees
latlatitude, in decimal degrees, North is positive, negative denotes South decimal degrees
ev_codeevent code; event type plus sequential number dimensionless
ev_typeevent type; CTD or Trace metal (TMR) dimensionless
seafloordepth of the seafloor; water depth from the shipboard 12 kHz Knudsen echosounder meters
activities_and_commentsactivities, comments, notes pertaining to event dimensionless

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Deployments

KN192-05

Website
Platform
R/V Knorr
Report
Start Date
2007-11-16
End Date
2007-12-13
Description
The South Atlantic subtropical gyre and Benguela Upwelling region were sampled for chemistry and biological properties relating to the trace metal nutrition and phytoplankton diversity and productivity. Specifically cobalt and iron dissolved seawater concentrations will be measured and related to the abundance of cyanobacteria including nitrogen fixers and eukaryotic phytoplankton. The phytoplankton of the Benguela Upwelling region were also examined to determine if their growth was iron or cobalt limited. A total of 27 station locations were occupied in the study area to collect the water chemistry and biological samples for these analyses (see cruise track). Iron and cobalt analyses will be conducted using inductively coupled plasma mass spectrometry and cathodic stripping voltammetry electrochemical methods. The sample preparation and subsequent analyses are technically demanding, but data generated from the cruise samples are being contributed beginning in mid 2009. The CoFeMUG KN192-5 cruise was supported by NSF OCE award # 0452883http://www.nsf.gov/awardsearch/showAward.do?AwardNumber=0452883 A station map showing the 27 sampling locations is available as a PDF file. Original cruise data are available from the NSF R2R data catalog CoFeMUG - South Atlantic 2007 Cruise Participant List 1. Mak Saito (Chief Scientist/WHOI) 2. Abigail Noble (Saito/WHOI) 3. Alysia Cox (Saito/WHOI) 4. Whitney Krey (Delong/Saito/MIT/WHOI) 5. Carl Lamborg (clamborg AT whoi.edu/WHOI) 6. Phoebe Lam (pjlam AT whoi.edu WHOI) 7. Chad Hammerschmidt (chammerschmidt AT whoi.edu, Wright State) 8. Caitlin Frame (cframe AT whoi.edu, WHOI/Casciotti Student) 9. Tyler Goepfert (tgoepfert AT whoi.edu Webb/Saito) 10. Jill Sohm (sohm AT usc.edu) 11. Maria Intermaggio 12. Jack DiTullio (leep AT cofc.edu U. Charleston) 13. Peter Lee (DiTullio U. Charleston) 14. Sarah Riseman (DiTullio U. Charleston) 15. Amanda McLenan (amanda.mclennon AT gmail.com, DiTullio U. Charleston) 16. Mike Seracki (Bigelow) 17. Nicole Poulton (Bigelow) 18. Juan Alba, juanalba AT usp.br (Bigelow) 19. Jane Heywood (Bigelow) 20. Gabrielle Rocap (rocap AT whoi.edu, U. Washington) 21. Emily Nahas (enahas AT u.washington.edu) 22. Michele Wrable (mlw22 AT u.washington.edu) 23. Bob Morris (rmorris AT lifesci.ucsb.edu) 24. Christian Frazar (Chris, U. Washington, Morris lab) 25. Jason Hilton (Zehr, UCSC) 26. Reserved for Angolan Observers 27. Reserved for Angolan Observers Collecting GEOTRACES-compliant samples for: 1. Laura Robinson (Pa Th isotopes) 2. Bob Anderson (Pa Th isotopes - intercalibration) 3. Olivier Rouxel (Se and Fe isotopes) 4. Karen Casciotti (N isotopes) 5. Ben Reynolds (Si and Fe isotopes) 6. Chris Measures (Al) 7. Kristin Buck (FeL)


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Project Information

Cobalt, Iron and Micro-organisms from the Upwelling zone to the Gyre (CoFeMUG)

Coverage: South Atlantic subtropical gyre and Benguela upwelling region


The geochemistries of dissolved cobalt (Co) and iron (Fe) in the oceanic water column share several characteristics such as extremely low concentrations, redox chemistry, low solubility,and utilization as micronutrients by marine microbes. Iron has been the subject of considerable research focus in recent years due to its role in limiting phytoplankton productivity in oceanic and coastal upwelling environments. Cobalt has been much less studied, but recent data show it may be important in influencing primary productivity or phytoplankton community composition in certain geographical areas.

The CoFeMUG project predated GEOTRACES, so while it is not formally recognized as a GEOTRACES section, it is considered a GEOTRACES-related project and the CoFeMUG data are GEOTRACES compliant.

State-of-the-art geochemical and molecular biological techniques were used to address biogeochemical questions in the South Atlantic, and focus especially on the two trace metals, cobalt and iron. The 27-day cruise in November and December 2007 to the South Atlantic was designed to study cobalt and iron biogeochemistry and focus on four major hypotheses.

(1) Large fluxes of labile cobalt are associated with upwelling systems even in Aeolian dominated environments.
(2) Cobalt and phosphate show correlations in (and only in) surface waters due to micronutrient utilization and rapid remineralization. The slope of the correlation is dependent on the chemical speciation of cobalt.
(3) The absence of Trichodesmium populations in the subtropical and tropical South Atlantic is caused by iron limitation.
(4) Based on work from the California and Peru Upwelling regimes, primary productivity in the Benguela upwelling regime off of South West Africa may be iron limited or iron-cobalt colimited.

A combination of geochemical and biological/molecular analyses were made across an oligotrophic-upwelling transition to examine how changing metal regimes affect the physiology and growth of the important primary producers Trichodesmium and Synechococcus.

CoFeMUG project results are published in:
Noble, Abigail E., Carl H. Lamborg, Dan C. Ohnemus, Phoebe J. Lam, Tyler J. Goepfert, Chris I. Measures, Caitlin H. Frame, Karen L. Casciotti, Giacomo R. DiTullio, Joe Jennings, and Mak A. Saito (2012) Basin-scale inputs of cobalt, iron, and manganese from the Benguela-Angola front to the South Atlantic Ocean. Limnology & Oceanography. Vol. 57(4), July 2012. pgs 989-1010. doi:10.4319/lo.2012.57.4.0989 (www.aslo.org/lo/toc/vol_57/issue_4/0989.pdf)



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Program Information

Ocean Carbon and Biogeochemistry (OCB)


Coverage: Global


The Ocean Carbon and Biogeochemistry (OCB) program focuses on the ocean's role as a component of the global Earth system, bringing together research in geochemistry, ocean physics, and ecology that inform on and advance our understanding of ocean biogeochemistry. The overall program goals are to promote, plan, and coordinate collaborative, multidisciplinary research opportunities within the U.S. research community and with international partners. Important OCB-related activities currently include: the Ocean Carbon and Climate Change (OCCC) and the North American Carbon Program (NACP); U.S. contributions to IMBER, SOLAS, CARBOOCEAN; and numerous U.S. single-investigator and medium-size research projects funded by U.S. federal agencies including NASA, NOAA, and NSF.

The scientific mission of OCB is to study the evolving role of the ocean in the global carbon cycle, in the face of environmental variability and change through studies of marine biogeochemical cycles and associated ecosystems.

The overarching OCB science themes include improved understanding and prediction of: 1) oceanic uptake and release of atmospheric CO2 and other greenhouse gases and 2) environmental sensitivities of biogeochemical cycles, marine ecosystems, and interactions between the two.

The OCB Research Priorities (updated January 2012) include: ocean acidification; terrestrial/coastal carbon fluxes and exchanges; climate sensitivities of and change in ecosystem structure and associated impacts on biogeochemical cycles; mesopelagic ecological and biogeochemical interactions; benthic-pelagic feedbacks on biogeochemical cycles; ocean carbon uptake and storage; and expanding low-oxygen conditions in the coastal and open oceans.


U.S. GEOTRACES (U.S. GEOTRACES)


Coverage: Global


GEOTRACES is a SCOR sponsored program; and funding for program infrastructure development is provided by the U.S. National Science Foundation.

GEOTRACES gained momentum following a special symposium, S02: Biogeochemical cycling of trace elements and isotopes in the ocean and applications to constrain contemporary marine processes (GEOSECS II), at a 2003 Goldschmidt meeting convened in Japan. The GEOSECS II acronym referred to the Geochemical Ocean Section Studies To determine full water column distributions of selected trace elements and isotopes, including their concentration, chemical speciation, and physical form, along a sufficient number of sections in each ocean basin to establish the principal relationships between these distributions and with more traditional hydrographic parameters;

* To evaluate the sources, sinks, and internal cycling of these species and thereby characterize more completely the physical, chemical and biological processes regulating their distributions, and the sensitivity of these processes to global change; and

* To understand the processes that control the concentrations of geochemical species used for proxies of the past environment, both in the water column and in the substrates that reflect the water column.

GEOTRACES will be global in scope, consisting of ocean sections complemented by regional process studies. Sections and process studies will combine fieldwork, laboratory experiments and modelling. Beyond realizing the scientific objectives identified above, a natural outcome of this work will be to build a community of marine scientists who understand the processes regulating trace element cycles sufficiently well to exploit this knowledge reliably in future interdisciplinary studies.

Expand "Projects" below for information about and data resulting from individual US GEOTRACES research projects.



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Funding

Funding SourceAward
NSF Division of Ocean Sciences (NSF OCE)

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