Attributes {
 s {
  cruise_id {
    String bcodmo_name "cruise_id";
    String description "Official cruise identifier.";
    String long_name "Cruise Id";
    String units "dimensionless";
  }
  sta {
    Byte _FillValue 127;
    String _Unsigned "false";
    Byte actual_range 5, 27;
    String bcodmo_name "sta";
    String description "Station number.";
    String long_name "Sta";
    String units "dimensionless";
  }
  latitude {
    String _CoordinateAxisType "Lat";
    Float64 _FillValue NaN;
    Float64 actual_range -25.0, -12.0;
    String axis "Y";
    String bcodmo_name "latitude";
    Float64 colorBarMaximum 90.0;
    Float64 colorBarMinimum -90.0;
    String description "Latitude; North is positive.";
    String ioos_category "Location";
    String long_name "Latitude";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P09/current/LATX/";
    String standard_name "latitude";
    String units "degrees_north";
  }
  longitude {
    String _CoordinateAxisType "Lon";
    Float64 _FillValue NaN;
    Float64 actual_range -20.0, 14.5;
    String axis "X";
    String bcodmo_name "longitude";
    Float64 colorBarMaximum 180.0;
    Float64 colorBarMinimum -180.0;
    String description "Longitude; East is positive. Calculated by BCO-DMO from the original PI-provided lon_360 values.";
    String ioos_category "Location";
    String long_name "Longitude";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P09/current/LONX/";
    String standard_name "longitude";
    String units "degrees_east";
  }
  lon_360 {
    Float32 _FillValue NaN;
    Float32 actual_range 0.0, 357.5;
    String bcodmo_name "lon_360";
    Float64 colorBarMaximum 180.0;
    Float64 colorBarMinimum -180.0;
    String description "Longitude measured from 0 to 360 degrees.";
    String long_name "Longitude";
    String standard_name "longitude";
    String units "decimal degrees";
  }
  press {
    Float64 _FillValue NaN;
    Float64 actual_range 9.0, 5106.0;
    String bcodmo_name "pressure";
    String description "Pressure.";
    String long_name "Press";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/PRESPR01/";
    String units "decibars (db)";
  }
  ev_code {
    String bcodmo_name "event code";
    String description "Event code; type and number of sampling event; matches cruise event log.";
    String long_name "Ev Code";
    String units "dimensionless";
  }
  event {
    Int32 _FillValue 2147483647;
    Int32 actual_range 11220908, 12111150;
    String bcodmo_name "event";
    String description "Event number from the cruise event log.";
    String long_name "Event";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/EVTAGFL/";
    String units "dimensionless";
  }
  date_event {
    Int32 _FillValue 2147483647;
    Int32 actual_range 20071122, 20071211;
    String bcodmo_name "date";
    String description "Year-month-day of the event; added by BCO-DMO from the cruise event log. in the format YYYYmmdd";
    String long_name "Date Event";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/ADATAA01/";
    String units "unitless";
  }
  N2O {
    Float32 _FillValue NaN;
    Float32 actual_range 6.8, 49.3;
    String bcodmo_name "Nitrous Oxide";
    String description "Dissolved N2O concentration.";
    String long_name "N2 O";
    String units "nanomoles per liter (nm/L)";
  }
  d15Nbulk_N2O {
    Float32 _FillValue NaN;
    Float32 actual_range -0.1, 9.1;
    String bcodmo_name "unknown";
    String description "d15Nbulk-N2O = average (bulk) isotope ratio (15N/14N) of both nitrogen atoms in N2O. Calculated as d15Nbulk-N2O = (d15Na-N2O + d15Nb-N2O)/2; referenced to atmospheric N2.";
    String long_name "D15 Nbulk N2 O";
    String units "per mil (?)";
  }
  SP_N2O {
    Float32 _FillValue NaN;
    Float32 actual_range 5.3, 25.2;
    String bcodmo_name "unknown";
    String description "SP-N2O = site preference of 15N in N2O. Calculated as (d15Na-N2O - d15Nb-N2O); the difference between d15Na-N2O and d15Nb-N2O.";
    String long_name "SP N2 O";
    String units "per mil (?)";
  }
  d18O_N2O {
    Float32 _FillValue NaN;
    Float32 actual_range 37.5, 52.2;
    String bcodmo_name "unknown";
    String description "d18O-N2O = isotope ratio (18O/16O) of oxygen in N2O. Calculated as d18O = ({[18O]/[16O]sample}/{[18O]/[16O]standard} -1) x 1000?; referenced to VSMOW.";
    String long_name "D18 O N2 O";
    String units "per mil (?)";
  }
  d15Na_N2O {
    Float32 _FillValue NaN;
    Float32 actual_range 6.1, 19.8;
    String bcodmo_name "unknown";
    String description "d15Na-N2O = isotope ratio (15N/14N) in the internal nitrogen of N2O; d15Na-N2O = ({[15N]/[14N]a,sample}/{[15N]/[14N]a,standard} -1) x 1000?; referenced to atmospheric N2 as the standard.";
    String long_name "D15 Na N2 O";
    String units "per mil (?)";
  }
  d15Nb_N2O {
    Float32 _FillValue NaN;
    Float32 actual_range -9.5, 2.1;
    String bcodmo_name "unknown";
    String description "d15Nb-N2O = isotope ratio (15N/14N) in the external nitrogen of N2O; d15Nb-N2O = ({[15N]/[14N]b,sample}/{[15N]/[14N]b,standard} -1) x 1000?; referenced to atmospheric N2 as the standard.";
    String long_name "D15 Nb N2 O";
    String units "per mil (?)";
  }
 }
  NC_GLOBAL {
    String access_formats ".htmlTable,.csv,.json,.mat,.nc,.tsv,.esriCsv,.geoJson";
    String acquisition_description "Single water samples for N2O analyses were collected from acid-cleaned,
Teflon-coated X-Niskin sampling bottles (OceanTest Equipment) of 8-liter
capacity deployed on an epoxy-coated rosette (Sea-Bird Electronics) as
described in Noble et al. (2012). Immediately after rosette recovery, water
samples were collected by twice overfilling 160 ml glass serum bottles
(Wheaton prod. no. 223748) from the bottom up using tygon tubing attached to
each niskin bottle. A small headspace was introduced into each sample by
pipetting 1 ml of sample off the top. The sample was then poisoned with 100 ul
of saturated HgCl2 solution and sealed with gray butyl septa (MicroLiter
Analytics prod. no. 20-0025) and aluminum crimps. Poisoned samples were stored
for several months in the dark at room temperature before analysis.
 
Isotopic analyses of N2O were made using a Finnigan DELTA PLUS XP IRMS
calibrated for isotopomer-specific measurements (see Frame & Casciotti (2010)
for details) and referenced against injections of a calibrated N2O reference
tank (d15Nbulk = 0.31\\u2030, SP = -1.2\\u2030, d18O = 40.85\\u2030 as calibrated
by S. Toyoda, Toykyo Tech) with quality control checks against analyses of
tropospheric air samples. Bottles were purged with He and N2O was trapped on-
line with a custom-built purge and trap system (McIlvin & Casciotti, 2010).
The molar amount of N2O was determined from each bottle using a constant
linear relationship of m/z 44 peak area to molar quantity of N2O which is 2.15
Vs per nanomole of N2O, then converted to a concentration by dividing the
molar amount by the volume of sample extracted (154 ml). The ratios of sample
N2O to reference gas N2O values of m/z 31/30, 45/44, and 46/44 were corrected
for a small linear dependence of these values on the sample peak area (see
McIlvin and Casciotti 2010), with all ratios corrected to a peak area of 20
Vs. For a 160 ml water sample containing 2.2 nmole of N2O (typical of the
lowest concentrations in this dataset), the precision of the d18O =
\\u00b10.25\\u2030, d15Nbulk = \\u00b10.09\\u2030, and SP = \\u00b10.33\\u2030.
Additional details about measurement precision are included in McIlvin &
Casciotti (2010). Triplicate samples of tropospheric N2O from Woods Hole, MA
had _d15Na = 15.0 \\u00b1 0.1\\u2030, _d15Nb = \\u22121.9 \\u00b1 0.1\\u2030, d_18O
= 44.4 \\u00b1 0.2\\u2030, _d15Nbulk = 6.5 \\u00b1 0.1\\u2030, SP = 16.9 \\u00b1
0.1\\u2030, and m/z 44 peak area = 15.6 \\u00b1 0.2 Vs. All cruise data are
included here except two measurements with background interference.";
    String awards_0_award_nid "54681";
    String awards_0_award_number "OCE-0452883";
    String awards_0_data_url "http://www.nsf.gov/awardsearch/showAward.do?AwardNumber=0452883";
    String awards_0_funder_name "NSF Division of Ocean Sciences";
    String awards_0_funding_acronym "NSF OCE";
    String awards_0_funding_source_nid "355";
    String awards_0_program_manager "Donald L. Rice";
    String awards_0_program_manager_nid "51467";
    String awards_1_award_nid "55017";
    String awards_1_award_number "OCE-1031271";
    String awards_1_data_url "http://www.nsf.gov/awardsearch/showAward.do?AwardNumber=1031271";
    String awards_1_funder_name "NSF Division of Ocean Sciences";
    String awards_1_funding_acronym "NSF OCE";
    String awards_1_funding_source_nid "355";
    String awards_1_program_manager "Donald L. Rice";
    String awards_1_program_manager_nid "51467";
    String awards_2_award_nid "55159";
    String awards_2_award_number "OCE-0928414";
    String awards_2_data_url "http://nsf.gov/awardsearch/showAward?AWD_ID=0928414&HistoricalAwards=false";
    String awards_2_funder_name "NSF Division of Ocean Sciences";
    String awards_2_funding_acronym "NSF OCE";
    String awards_2_funding_source_nid "355";
    String awards_2_program_manager "Donald L. Rice";
    String awards_2_program_manager_nid "51467";
    String awards_3_award_nid "529604";
    String awards_3_award_number "OCE-0752291";
    String awards_3_data_url "http://www.nsf.gov/awardsearch/showAward?AWD_ID=0752291";
    String awards_3_funder_name "NSF Division of Ocean Sciences";
    String awards_3_funding_acronym "NSF OCE";
    String awards_3_funding_source_nid "355";
    String awards_3_program_manager "Donald L. Rice";
    String awards_3_program_manager_nid "51467";
    String cdm_data_type "Other";
    String comment "Dissolved nitrous oxide and stable isotopes/isotopomers 
  CoFeMUG cruise KN192-05 
 PI: Karen Casciotti (Stanford) 
 Co-PI: Caitlin Frame (University of Basel) 
 Version: 17 Sept 2014";
    String Conventions "COARDS, CF-1.6, ACDD-1.3";
    String creator_email "info@bco-dmo.org";
    String creator_name "BCO-DMO";
    String creator_type "institution";
    String creator_url "https://www.bco-dmo.org/";
    String data_source "extract_data_as_tsv version 2.3  19 Dec 2019";
    String date_created "2014-10-03T15:33:32Z";
    String date_modified "2020-03-31T17:27:18Z";
    String defaultDataQuery "&time<now";
    String doi "10.26008/1912/bco-dmo.529599.1";
    Float64 Easternmost_Easting 14.5;
    Float64 geospatial_lat_max -12.0;
    Float64 geospatial_lat_min -25.0;
    String geospatial_lat_units "degrees_north";
    Float64 geospatial_lon_max 14.5;
    Float64 geospatial_lon_min -20.0;
    String geospatial_lon_units "degrees_east";
    String history "2024-11-08T08:42:18Z (local files)
2024-11-08T08:42:18Z https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_529599.das";
    String infoUrl "https://www.bco-dmo.org/dataset/529599";
    String institution "BCO-DMO";
    String instruments_0_acronym "IR Mass Spec";
    String instruments_0_dataset_instrument_description "Isotopic analyses of N2O were made using a Finnigan DELTA PLUS XP IRMS calibrated for isotopomer-specific measurements; see Frame & Casciotti (2010) for details.";
    String instruments_0_dataset_instrument_nid "529615";
    String instruments_0_description "The Isotope-ratio Mass Spectrometer is a particular type of mass spectrometer used to measure the relative abundance of isotopes in a given sample (e.g. VG Prism II Isotope Ratio Mass-Spectrometer).";
    String instruments_0_instrument_external_identifier "https://vocab.nerc.ac.uk/collection/L05/current/LAB16/";
    String instruments_0_instrument_name "Isotope-ratio Mass Spectrometer";
    String instruments_0_instrument_nid "469";
    String instruments_0_supplied_name "Finnigan DELTA PLUS XP IRMS";
    String instruments_1_acronym "TM Bottle";
    String instruments_1_dataset_instrument_description "Single water samples for N2O analyses were collected from acid-cleaned, Teflon-coated X-Niskin sampling bottles (OceanTest Equipment) of 8-liter capacity deployed on an epoxy-coated rosette (Sea-Bird Electronics).";
    String instruments_1_dataset_instrument_nid "529614";
    String instruments_1_description "Trace metal (TM) clean rosette bottle used for collecting trace metal clean seawater samples.";
    String instruments_1_instrument_external_identifier "https://vocab.nerc.ac.uk/collection/L05/current/30/";
    String instruments_1_instrument_name "Trace Metal Bottle";
    String instruments_1_instrument_nid "493";
    String instruments_1_supplied_name "Teflon-coated X-Niskin sampling bottles (Ocean Test Equipment)";
    String keywords "bco, bco-dmo, biological, chemical, code, cruise, cruise_id, d15, d15Na_N2O, d15Nb_N2O, d15Nbulk_N2O, d18, d18O_N2O, data, dataset, date, date_event, dmo, erddap, ev_code, event, latitude, lon_360, longitude, management, N2O, nbulk, oceanography, office, preliminary, press, SP_N2O, sta";
    String license "https://www.bco-dmo.org/dataset/529599/license";
    String metadata_source "https://www.bco-dmo.org/api/dataset/529599";
    Float64 Northernmost_Northing -12.0;
    String param_mapping "{'529599': {'lat': 'flag - latitude', 'press': 'flag - depth', 'lon': 'flag - longitude'}}";
    String parameter_source "https://www.bco-dmo.org/mapserver/dataset/529599/parameters";
    String people_0_affiliation "Stanford University";
    String people_0_person_name "Karen L. Casciotti";
    String people_0_person_nid "50980";
    String people_0_role "Principal Investigator";
    String people_0_role_type "originator";
    String people_1_affiliation "University of Basel (Universitat Basel)";
    String people_1_person_name "Caitlin Frame";
    String people_1_person_nid "529608";
    String people_1_role "Co-Principal Investigator";
    String people_1_role_type "originator";
    String people_2_affiliation "Stanford University";
    String people_2_person_name "Karen L. Casciotti";
    String people_2_person_nid "50980";
    String people_2_role "Contact";
    String people_2_role_type "related";
    String people_3_affiliation "Woods Hole Oceanographic Institution";
    String people_3_affiliation_acronym "WHOI BCO-DMO";
    String people_3_person_name "Shannon Rauch";
    String people_3_person_nid "51498";
    String people_3_role "BCO-DMO Data Manager";
    String people_3_role_type "related";
    String project "CoFeMUG";
    String projects_0_acronym "CoFeMUG";
    String projects_0_description "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)";
    String projects_0_end_date "2008-03";
    String projects_0_geolocation "South Atlantic subtropical gyre and Benguela upwelling region";
    String projects_0_name "Cobalt, Iron and Micro-organisms from the Upwelling zone to the Gyre";
    String projects_0_project_nid "2067";
    String projects_0_start_date "2005-03";
    String publisher_name "Biological and Chemical Oceanographic Data Management Office (BCO-DMO)";
    String publisher_type "institution";
    String sourceUrl "(local files)";
    Float64 Southernmost_Northing -25.0;
    String standard_name_vocabulary "CF Standard Name Table v55";
    String subsetVariables "cruise_id";
    String summary "Dissolved N2O concentration and stable isotope/isotopomer composition measurements made from samples from acid-cleaned, Teflon-coated X-Niskin sampling bottles on the CoFeMUG cruise (KN192-05).";
    String title "[Dissolved Nitrous Oxide] - Dissolved N2O concentration and stable isotope/isotopomer composition measurements from R/V Knorr cruise KN192-05 in the South Atlantic subtropical gyre and Benguela upwelling region in 2007 (CoFeMUG project) (Cobalt, Iron and Micro-organisms from the Upwelling zone to the Gyre)";
    String version "1";
    Float64 Westernmost_Easting -20.0;
    String xml_source "osprey2erddap.update_xml() v1.3";
  }
}