PANGAEA_993688 Dissolved methane concentrations in seawater during Lomrog III cruise, Arctic Ocean Verdugo, Josefa; Farías, Laura Dissolved methane concentrations in seawater during Lomrog III cruise, Arctic Ocean 2026-04-22 PANGAEA Dataset https://doi.pangaea.de/10.1594/PANGAEA.993688 Investigator Josefa Verdugo Josefa.verdugo@bio.au.dk Earth Science Event label Latitude of event Longitude of event DATE/TIME DEPTH, water Methane Salinity Temperature, water geoscientificInformation Arctic Ocean CTD/Rosette dissolved methane concentration LOMROG-III LR12s01 LR12s02 LR12s03 LR12s04 LR12s05 LR12s06 LR12s07 LR12s08 LR12s09 LR12s10 LR12S10 LR12s11 LR12S11 LR12s12 LR12S12 CTD/Rosette Gas chromatograph, Varian Inc., 3380 Oden 2012-08-02 2012-09-11 Complete 82.195833 89.265 -69.4115 78.242667 9.628 m (DEPTH, water) 4350.0 m (DEPTH, water) unrestricted CC-BY-4.0: Creative Commons Attribution 4.0 International English PANGAEA Data Publisher for Earth & Environmental Science https://www.pangaea.de/ Data Center Contact Michael Diepenbroek info@pangaea.de

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Bremen Bremen 28359 Germany online 385 data points text/tab-separated-values Farías, Laura; Verdugo, Josefa (2025): Nitrous oxide in seawater during Lomrog III cruise, Arctic Ocean (2012) [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.977808 Marcussen, Christian (2012): Lomonosov Ridge off Greenland 2012 (LOMROG III) - Cruise Report. Geological Survey of Denmark and Greenland, Danish Ministry of Climate and Energy, 222 pp, hdl:10013/epic.45351.d001 Stratmann, Tanja; Lund-Hansen, Lars Chresten; Sorrell, Brian K; Markager, Stiig (2018): Concentrations of organic and inorganic nutrients and chlorophyll-a during cruise LOMROG III in the central Arctic Ocean [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.896134 Stratmann, Tanja; Lund-Hansen, Lars Chresten; Sorrell, Brian K; Markager, Stiig (2017): Concentrations of organic and inorganic bound nutrients and chlorophyll a in the Eurasian Basin, Arctic Ocean, early autumn 2012. Regional Studies in Marine Science, 9, 69-75, https://doi.org/10.1016/j.rsma.2016.11.008 Verdugo, Josefa; Damm, Ellen; Snoeijs, P; Díez, Beatriz; Farías, Laura (2016): Climate relevant trace gases (N2O and CH4) in the Eurasian Basin (Arctic Ocean). Deep Sea Research Part I: Oceanographic Research Papers, 117, 84-94, https://doi.org/10.1016/j.dsr.2016.08.016

The concentration of methane (CH4), along with temperature and salinity, were measured in the ice- covered Arctic Ocean within the Eurasian Basin (Verdugo et al., 2016; doi:10.1016/j.dsr.2016.08.016). The transect was conducted across the Nansen-Gakkel Ridge, from the Nansen Basin to the Amundsen Basin, covering depths from the surface (10 m) down to 4300 m. All sampling stations, except for ST 12, were covered by sea ice. Water samples were collected with a CTD-rosette sampler equipped with 24 Niskin Bottles. Gas sampling was carried out directly from 12 L Niskin bottles. Triplicate water samples for CH4 analyses were taken in 20 mL glass vials and preserved with 50 µL of saturated HgCl2. The vials were then sealed with a butyl-rubber septum and an aluminum cap to prevent bubble formation and stored in darkness at room temperature until laboratory analysis. CH4 concentrations were analyzed by creating 5 mL of ultra-pure helium headspace, followed by equilibration in the vial, and then quantified with a gas chromatograph (GC). A Varian 3380 GC, equipped with flame ionization detector (FID) maintained at 250 °C, and a capillary column GS-Q operated at 30 °C was used for analysis. A calibration curve was made with three standard concentrations for CH4 (1, 5, and 10 ppm, provided by Scotty Standards) and dry air. ** For all details see the full metadata description at "https://doi.pangaea.de/10.1594/PANGAEA.993688"!

http://en.wikipedia.org/wiki/ISO_8601 DATE/TIME https://doi.org/10.1016/j.dsr.2016.08.016 Climate relevant trace gases (N2O and CH4) in the Eurasian Basin (Arctic Ocean) https://doi.org/10.1016/j.rsma.2016.11.008 Concentrations of organic and inorganic bound nutrients and chlorophyll a in the Eurasian Basin, Arctic Ocean, early autumn 2012 https://doi.pangaea.de/10.1594/PANGAEA.896134 Concentrations of organic and inorganic nutrients and chlorophyll-a during cruise LOMROG III in the central Arctic Ocean https://doi.pangaea.de/10.1594/PANGAEA.977808 Nitrous oxide in seawater during Lomrog III cruise, Arctic Ocean (2012) https://hdl.handle.net/10013/epic.45351.d001 Lomonosov Ridge off Greenland 2012 (LOMROG III) - Cruise Report DIF 9.4 2026-04-22 2026-08-11