Dataset: GT10-11 - Particulate composition
Deployment: KN199-04

Size-fractionated major and minor particle composition and concentration
Principal Investigator: 
Phoebe J. Lam (Woods Hole Oceanographic Institution, WHOI)
Contact: 
Phoebe J. Lam (Woods Hole Oceanographic Institution, WHOI)
BCO-DMO Data Manager: 
Nancy Copley (Woods Hole Oceanographic Institution, WHOI BCO-DMO)
Project: 
Current State: 
Final no updates expected
Version: 
14 June 2013
Deployment Synonyms:
 GA03,  GT10,  USGT-NAT-2010,  KN199-4,  GNAT,  U.S. GEOTRACES NAZT Leg 1,  knorr199-4/5,  Section Cruise (GA03),  316N20101015
Version Date: 
2013-06-14
Description

Publications resulting from this data:
Lam, P. J., D. C. Ohnemus, and M. E. Auro. 2015. Size-fractionated major particle composition and concentrations from the US GEOTRACES North Atlantic Zonal Transect. Deep Sea Research Part II: Topical Studies in Oceanography 116: 303-320. 10.1016/j.dsr2.2014.11.020

Ohnemus, D. C., & Lam, P. J. (2015). Cycling of lithogenic marine particles in the US GEOTRACES North Atlantic transect. Deep Sea Research Part II: Topical Studies in Oceanography, 116, 283–302. doi:10.1016/j.dsr2.2014.11.019

Changes to each version:

Version 5.1: no change in data, just re-ordered columns.

Version 5: submitted to BCO-DMO 2018-07-18 - Metadata: error corrected in Parameter names, descriptions, units for "Litho_AlUCC" and "Litho_TiDust" (equation should be divided by 1000 ng/ug--data were correct) - Many parameters, especially particulate trace metals in the large size fraction (*_sink) and some very low abundance trace metals in the small size fraction (*_susp), appeared as 0 because not enough decimal places were specified. This has been corrected for all particulate trace metals (parameters from Ag to Zn, inclusive) - Quality flags for Cu, Ni, P, V, Zn changed from QF=8 to QF=1

Version 4: submitted to BCO-DMO 2014-12-11
- Longitude for GT11-10 (BATS) changed from 295.27°E to 295.9°E to be consistent with event log from 
- Added missing pTM data and parameters that derive from pTM (eg. Litho, Fe(OH)3, MnO2, SPM) for GT11-20, 3500m and GT11-22, 3600m
- SPM_LithoTiDust_susp and SPM_LithoTiDust_sink, which were calculated using a Ti-based estimate of lithogenic material, have been replaced by SPM_susp and SPM_sink, which were calculated using an Al-based estimate of lithogenic material.  Details are in Lam, P.J., et al., Size-fractionated major particle composition and concentrations from the US GEOTRACES North Atlantic Zonal Transect. Deep-Sea Res. II (2014), http://dx.doi.org/10.1016/j.dsr2.2014.11.020.
- Most of the PIC_susp data for the meridional stations (GT10-1,3,5,7) were found to be suspect.   Quality flags for PIC_susp and CaCO3_susp for affected samples have been changed to QF=8. The following variables are calculated using PIC_susp and are thus also affected: POC_susp, POM_susp, and SPM_susp.  For these parameters, we used the mean PIC:TPC ratio of oligotrophic samples with high quality PIC to estimate PIC_susp from TPC_susp. Details are in Lam, P.J., et al., Size-fractionated major particle composition and concentrations from the US GEOTRACES North Atlantic Zonal Transect. Deep-Sea Res. II (2014), http://dx.doi.org/10.1016/j.dsr2.2014.11.020

Version 3: submitted to BCO-DMO 2013-10-31
    -We have changed the definitions of the Quality Flags (QF) to the following to reflect incorporation of intercalibration tests:
        -QF=0: good, passed intercalibration
        -QF=1: unknown - oceanographically consistent, but no intercalibration done (previous versions: anomalously high or low)
        -QF=4: questionable - below detection, or anomalously high or low (previous versions: below detection)
        -QF=8: bad - intercalibration issues to be resolved, or known issue with sample
        -see end of this document for more information
    -We have updated quality flags for elements based on the revised definitions above
        -QF=1: opal, TPC, PIC, POC, POM, CaCO3, Litho_AlUCC, Litho_TiDust, Fe(OH)3_TiDust, MnO2_TiDust, SPM_lithoTiDust, Ag, Nd, Th, Y
        -QF=8: Cu, Ni, P, V, Zn
    -TPC_susp and TPC_sink in versions 2 and 2b were corrupted. This has been fixed.
    -TPC_sink for the deep cast of GT11-8 was entered incorrectly. This has been fixed
    -TPC_sink and parameters derived from it (POC_sink, POM_sink, SPM_lithoTidust_sink) for the deep casts of KN199-4 GT10-5, -10, -11, -12 have been found to be anomalously low; this is likely due to improper storage of the samples before analysis, which led to degradation of the organic matter.  The quality control flags for affected samples have been downgraded to 'bad' (QF=8)
    -Table of blanks and detection limits now has values for phosphorus
    -This metadata document now contains a table of recoveries for three certified reference materials (CRMs) relevant for our particulate trace metal data

Version 2b: submitted to BCO-DMO 2013-06-14
    -'depth_n', the nominal target (uncorrected) pump depth has been added to the dataset. The originally submitted 'depth' column remains the final, corrected, and most accurate pump depth.

Version 2: submitted to BCO-DMO 2013-04-09
    -PIC data have gone through an additional round of quality control and have been adjusted and improves oceanographic consistency; see section 2.3 for details.  Affects CaCO3, POC, POM, SPM.
    -A mistake was found in the calculations for MnO2 and Fe(OH)3 (the weight dust ratio was used instead of the molar dust ratio) and was fixed; see section 2.8
    -Like for the TEIs, we now also provide error estimates for each sample for TPC, POC, PIC, opal, Litho, MnO2, Fe(OH)3 and SPM.  Details for how errors are calculated for each parameter are in the relevant sections below.
    -Although our standard detection limit is defined as three times the standard deviation of our dipped blank filters, we redefined the detection limit for Ti as 1 standard deviation of the blank.  This increases the number of values reported for Ti, affecting MnO2, Fe(OH)3, lithogenics, and SPM.
    -'PIC_method' was added to the parameter list; see list and definitions of parameters
    -We have added a table of blanks and detection limits for particulate TEIs to section 2.6 of this document
    -Expected changes in next version: all TEI values below the detection limit (QF=4) are currently blank. We intend to upload the actual values in the next version.

Version 1: submitted to BCO-DMO 2013-02-01

More information about this dataset deployment