GLODAPv2.2019 - an update of GLODAPv2

• Published in: Earth System Science Data
• Main Authors: Olsen, A, Lange, N, Key, RM, Tanhua, T, Alvarez, M, Becker, S, Bittig, HC, Carter, BR, Cotrim Da Cunha, L, Feely, RA, Van Heuven, S, Hoppema, M, Ishii, M, Jeansson, E, Jones, SD, Jutterstrom, S, Karlsen, MK, Kozyr, A, Lauvset, SK, Lo Monaco, C, Murata, A, Perez, FF, Pfeil, B, Schirnick, C, Steinfeldt, R, Suzuki, T, Telszewski, M, Tilbrook, B, Velo, A, Wanninkhof, R
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus GmbH 2019
• Subjects: Global Ocean Data Analysis Project; GLODAP; ocean biogeochemical data; GLODAPv2; Arctic; Pacific; Indian
• Online Access: https://eprints.utas.edu.au/34460/; https://eprints.utas.edu.au/34460/1/137401%20-%20GLODAPv2.2019%20-%20An%20update%20of%20GLODAPv2.pdf

The Global Ocean Data Analysis Project (GLODAP) is asynthesis effort providing regular compilations of surface to bottom oceanbiogeochemical data, with an emphasis on seawater inorganic carbon chemistryand related variables determined through chemical analysis of water samples.This update of GLODAPv2, v2.2019, adds data from 116 cruises to the previousversion, extending its coverage in time from 2013 to 2017, while also addingsome data from prior years. GLODAPv2.2019 includes measurements from morethan 1.1 million water samples from the global oceans collected on 840cruises. The data for the 12 GLODAP core variables (salinity, oxygen,nitrate, silicate, phosphate, dissolved inorganic carbon, total alkalinity,pH, CFC-11, CFC-12, CFC-113, and CCl4) have undergone extensive qualitycontrol, especially systematic evaluation of bias. The data are available intwo formats: (i) as submitted by the data originator but updated to WOCEexchange format and (ii) as a merged data product with adjustments appliedto minimize bias. These adjustments were derived by comparing the data fromthe 116 new cruises with the data from the 724 quality-controlled cruises ofthe GLODAPv2 data product. They correct for errors related to measurement,calibration, and data handling practices, taking into account any known orlikely time trends or variations. The compiled and adjusted data product isbelieved to be consistent to better than 0.005 in salinity, 1 % in oxygen,2 % in nitrate, 2 % in silicate, 2 % in phosphate, 4 µmol kg−1 in dissolved inorganic carbon, 4 µmol kg−1 in totalalkalinity, 0.01–0.02 in pH, and 5 % in the halogenated transienttracers. The compilation also includes data for several other variables,such as isotopic tracers. These were not subjected to bias comparison oradjustments.The original data, their documentation and DOI codes are available in theOcean Carbon Data System of NOAA NCEI(https://www.nodc.noaa.gov/ocads/oceans/GLODAPv2_2019/, last access: 17 September 2019). Thissite also provides access to the merged data product, which is provided as asingle global file and as four regional ones – the Arctic, Atlantic, Indian,and Pacific oceans – under https://doi.org/10.25921/xnme-wr20(Olsen et al., 2019). Theproduct files also include significant ancillary and approximated data.These were obtained by interpolation of, or calculation from, measured data.This paper documents the GLODAPv2.2019 methods and provides a broad overviewof the secondary quality control procedures and results.