Dataset: Trace element concentrations in suspended particles collected from the GeoFISH during the R/V Thomas G. Thompson cruise TN303 from Peru to Tahiti in 2013 (U.S. GEOTRACES EPZT project)

This dataset comprises all trace element measurements made on suspended particulate samples collected by filtration from the towed fish (bottle data in a separate dataset) during the US GEOTRACES GP16 cruise, R/V Thomas G Thompson 303. It combines data produced at Bigelow Laboratory (upper water column) and at Rutgers University (intermediate and deep water column).  NOTE:  At station 18, near-plume depths were sampled in two separated casts deployed at two different times during the long station.  The results are interleaved in this data file, but can be distinguished and separated by using sequential GEOTRACES numbers (always every other number since only every other bottle was used for particle sampling).

This dataset contains total and labile particulate element concentrations data via Inductively-coupled plasma mass spectrometry.

Trace element concentrations in suspended particles were collected from the towed GeoFISH (bottle data are in a separate dataset) and then by filtration onto 0.45um Supor (Pall Gellman) polyethersulfone filters. Particulate matter on filters was completely digested in hot acids and resulting solutions were analyzed using inductively-coupled plasma mass spectrometry (ICP-MS). Labile (weak acid leachable) particulate element concentrations are also reported for the samples analyzed at Bigelow Labs.

Parameter names, definitions and Units:
Concentrations of total suspended particulate trace elements are indicated as the element symbol alone: Al, Ba, Cd, (Ce), Co, (Cr), Cu, Fe, La, Mn, (Nd), Ni, P, Pb, (Sc), Th, Ti, V, Y, Zn (elements in parentheses analyzed at Rutgers only). Concentrations of the labile fraction of these particulate elements are indicated as element names followed by the suffix ‘_L’. Volumetric concentrations and concentration errors for all particulate fractions (>0.45 um) are reported in units of pmol/L. The GEOTRACES sample number is in column ‘GEOTRC_SAMPNO’, and the analytical lab is found in column ‘Lab’ (where 1= Bigelow, 2=Rutgers).

Several elements were determined but are not reported here because data quality was compromised by large seasalt or process blank corrections, or because data quality simply has not been fully evaluated yet (REEs at Rutgers). However, it is possible that there is some future utility in these data, and we ask that users contact Bigelow and Rutgers who can provide the data on an individual basis. The analyzed but excluded elements include Mo, Sc, and Sr for Bigelow, and Ca, Mo, Rb, Sr, and the remaining REEs Pr, Sm, Eu, Tb, Gd, Dy, Ho, Er, Tm, Yb, and Lu for Rutgers. We expect that these REEs will be reported in a future iteration of this data report.

Uncertainties (errors) for both total and labile element concentrations are reported with the additional suffix “_Error”.  (N.B. DMO changed to "_err" for consistency.)

For samples (station/depth combinations) lacking replicate analyses (i.e. most samples; flag code generally ‘2’—see below for flag code descriptions), uncertainties are reported as propagated errors accounting for each step of analysis and data processing, as described below.

Access restrictions:
It is our understanding that access to the data will be restricted to the GEOTRACES Data Management Committee (DMC) and Standards and Intercalibration Committee (SIC) until the product is publicly released in the next Intermediate Data Product, currently August, 2017.

References:
Berger, C. J. M., S. M. Lippiatt, M. G. Lawrence, and K. W. Bruland. 2008. Application of a chemical leach technique for estimating labile particulate aluminum, iron, and manganese in the Columbia River plume and coastal waters off Oregon and Washington. Journal of Geophysical Research-Oceans 113.

Cutter, G. A., Andersson, P. S., Codispoti, L. A., Croot, P. L., Francois, R., Lohan, M. C., Obata, H. and Rutgers Van Der Loeff, M. M.: Sampling and Sample-handling Protocols for GEOTRACES Cruises,, 1–238 [online] Available from: http://www.geotraces.org/libraries/documents/Intercalibration/Cookbook.pdf, 2010.

Cutter, G.A. and Bruland, K.W. 2012. Rapid and non-contaminating sampling system for trace elements in global ocean surveys. Limnology & Oceanography: Methods 10: 425-436.

Ohnemus, D.C., M.E. Auro, R.M. Sherrell, M. Langerstrom, P.L. Morton, B.S. Twining, S. Rauschenberg, P.J. Lam. 2014. Laboratory intercomparison of marine particulate digestions including Piranha: a novel chemical method for dissolution of polyethersulfone filters. Limnology and Oceanography 12:530-547.

Planquette, H. and Sherrell, R.M. 2012. Sampling for particulate trace element determination using water sampling bottles: methodology and comparison to in situ pumps. Limnology & Oceanography: Methods 10: 367-388.

Twining, B. S., S. B. Baines, J. B. Bozard, S. Vogt, E. A. Walker, and D. M. Nelson. 2011. Metal quotas of plankton in the equatorial Pacific Ocean. Deep-Sea Research II 58: 325-341.

Twining, B.S., Rauschenberg, S., Morton, P.L., Ohnemus, D.C., Lam, P.J. 2015. Comparison of particulate trace element concentrations in the North Atlantic Ocean as determined with discrete bottle sampling and in situ pumping. Deep Sea Research Part II 116: 273-282.

Related files:

Blanks and Detection Limits and related derived quantities from Rutgers and Bigelow labs (png)
    Median process blanks for two labs compared (pmol for 1/2 filter digested)(png)
    Median percent process blank correction for reported data from two labs (png)
Total elemental recoveries for certified reference materials (CRMs) reported by each participating lab (png)
Original XL file.

Intercalibration for suspended particulate elements between Sherrell (Rutgers) and Twining (Bigelow) groups (docx)
    Duplicated Depths by Lab.png
    Duplicated Depths by Cast (Shallow-Intermediate).png
    Deplicated Depths by Cast (Intermediate-Deep).png

Original dataset - not separated into Bottle and Fish