Publishing Network for Geoscientific and Environmental Data
Not a member yet
441201 research outputs found
Sort by
Total mercury, monomethylmercury, and total carbon in sediments from the Southern Ocean and South Sandwich Trench during the PS133/1 expedition (3 – 9 November 2022)
No full textSediment cores for total mercury (Hg), monomethylmercury (MMHg), and total carbon (TC) were collected in the Southern Ocean and the South Sandwich Trench between 3 and 9 November 2022 during the PS133/1 expedition. Sampling depths ranged from approximately 3700 to 8000 m, using a multicorer (MUC) system. Total Hg concentrations were determined by thermal decomposition, amalgamation, and atomic absorption spectrophotometry (TDA–AAS) using a DMA-80 Direct Mercury Analyzer (Milestone). Monomethylmercury (MMHg) was analyzed by gas chromatography–cold vapor atomic fluorescence spectrometry (GC–CVAFS) following ethylation with sodium tetraethylborate on a KOH-digested aliquot, using a Brooks Rand manual system. Total carbon (TC) was measured using an elemental analyzer Euro EA 3000 (HEKAtech GmbH)
Dissolved methane concentrations, diffusive methane flux and Essential Ocean Variables (EOVs) in the German Bight in January 2024 (Sternfahrt 11)
No full textIn January 2024 a river flood by the Elbe and Weser resulted in very high discharge of freshwater into the German Bight. To follow this river, plume the RV Mya II cruised from Sylt and between Helgoland, Cuxhaven, Büsum. All instruments were set up in the MOSES laboratory container. Standard hydrographic parameters were determined with a pocket ferrybox running with ship's surface water supply. In addition, dissolved methane was determined continuously. We used a degassing unit which was using surface water from the ship's water supply. The gas mixture was subsequently analysed with a Greenhouse Gas Analyzer from LosGatos. Conversion to methane concentration was performed with water samples, from which the methane content was determined with gas chromatography. Atmospheric methane concentrations were obtained from the ICOS-station Helgoland. Wind speed was obtained from the ships meteorological system. The diffusive flux was calculated as outlined in the additional meta data description
Diversity of benthic foraminifera for the Marine Isotope Stage (MIS) 19 to MIS 28 interval of IODP Site 339-U1387, Gulf of Cadiz
No full textBenthic foraminifera C. pachyderma and P. ariminensis oxygen and carbon isotope records for the Marine Isotope Stage (MIS) 19 to MIS 28 interval of IODP Site 339-U1387, Gulf of Cadiz
No full textMid-to-late Holocene and LGM multiproxy temperature, stable isotope, and seawater δ18O data from the North Atlantic
No full textThis dataset comprises trace-metal and clumped isotope (Δ47) measurements on multiple species of benthic foraminifera from 13 sediment cores in the Northwest Atlantic (Cape Hatteras, Blake Outer Ridge, Bermuda Rise, and Corner Rise), as well as three additional cores retrieved south of Iceland. These cores were collected during Ocean Drilling Program Leg 172 in 1997, R/V Knorr cruises 178 and 198, and R/V Charles Darwin cruise 159 in 2004 as part of the RAPiD programme. The data span two time slices: the mid-to-late Holocene (MH; 2–6 ka BP) and the Last Glacial Maximum (LGM; 19–23 ka BP). Derived deep-ocean temperature and carbonate ion concentration (ΔCO₃²⁻) estimates are included, along with contemporaneous seawater oxygen-isotope values calculated using trace-metal- and Δ47-derived temperatures combined with previously published stable-isotope data (Wharton et al., 2024). Collectively, these data provide insights into the vertical hydrographic structure of the North Atlantic during the MH and LGM and help trace the origin of the water masses present in the Northwest Atlantic. Trace-metal analyses were performed using a Thermo Finnigan Element2 magnetic-sector inductively coupled plasma mass spectrometer (ICP-MS) at the University of Colorado Boulder. Δ47 analyses were performed using a Thermo Scientific Kiel IV carbonate preparation device coupled to a Thermo Scientific MAT 253 mass spectrometer (conventional DI method) and a Thermo Scientific 253 Plus mass spectrometer using the long-integration dual-inlet (LIDI) method
Carbon isotopic compositions of fatty acids in Melosira assemblages, and subsequently isolated unialgal cultures collected in June 2023 during the RV Kronprins Haakon cruise 2023-1 in Fram Strait
No full textDuring the AO2023-1 expedition (1-21 June 2023), Melosira assemblages were collected using a handpump at a sampling site in Fram Strait. In addition to performing physiological measurements and filtering the material for trophic markers (fatty acids, stable isotope ratios of fatty acids, sterols and highly branched isoprenoids (HBIs), living material was brought back to Akvaplan-niva in Oslo and two strains were established as unialgal cultures. The cultures are maintained in artificial seawater-based L1 medium at 4°C and 25 µmol m-2 s-1 light with a 16:8 L:D cycle. Lipids were extracted from freeze-dried samples following the method of Folch et al. (1957), using a dichloromethane/methanol mixture (2:1, v/v) in a sonication bath. The extracted lipids were converted to fatty acid methyl esters (FAMEs) and analyzed by gas chromatography (Agilent 6890N Network GC, Agilent Technologies) equipped with a DB-FFAP capillary column (30 m length, 0.25 mm inner diameter, 0.25 μm film thickness), split injection, and a flame ionization detector. The temperature program ranged from 160°C to 240°C. Carbon stable isotope ratios δ13C were measured directly from FA extracts for selected biomarker FAs—14:0, 16:0, 16:1(n-7), and 20:5(n-3)—using a Thermo GC-c-IRMS system. This setup included a Trace GC Ultra gas chromatograph, a GC Isolink interface, and a Delta V Plus isotope ratio mass spectrometer, all connected via a Conflo IV interface (Thermo Scientific). FAMEs, dissolved in hexane, were injected in splitless mode and separated on a DB-FFAP capillary column (60 m length, 0.25 mm inner diameter, 0.25 μm film thickness). Samples were analysed in triplicates. Stable isotope analysis was conducted to complement datasets on fatty acid and sterol proportions. Collectively, the datasets enable a detailed characterization of the biochemical composition of different Melosira arctica-dominated algal assemblages from the Arctic Ocean, and a comparison with a unialgal culture of this important species
Relative abundance of coccolithophore species in sediment core MedSeA-S7 retrieved from the Strait of Sicily during the MedSeA Cruise 2013
No full textRelative abundance of coccolithophore species in MedSeA-S7 sediment core, spanning from 1810 to 2010 years of the Common Era, examined under a polarized microscope at 1000x magnification (size fraction <63 um) at least 500 speciments were counted and identified
Continuous thermosalinograph oceanography along RV METEOR cruise track M211
No full textUnderway temperature and salinity data was collected along the cruise track with two autonomous thermosalinograph (TSG) systems, each consisting of a SBE21 TSG together with a SBE38 Thermometer. Both systems worked independent from each other throughout the cruise. While temperature is taken at the water inlet in about 5 m depth, salinity is estimated within the interior TSG from conductivity and interior temperature. No validation against independent data was performed for temperature. Salinity was validated against independent water samples. Finally, TSG1 was chosen for publication. For details to all processing steps see Data Processing Report
Neodymium isotope gradients between ODP Sites 130-807 and 181-1123
No full textThe Neodymium isotope gradient between ODP Sites 130-807 and 181-1123 was calculated after interpolating both records at 5 kyr resolution using Acycle. NaN values indicate intervals without data. The age models follow Elderfield et al. (2012, doi:10.1126/science.1221294) and Feng et al. (2022, doi:10.1016/j.gloplacha.2022.103945)
Carbon isotope gradients between Sites ODP 130-807 and 181-1123
No full textThe stable carbon isotope (δ13C) gradient between ODP Sites 130-807 and 181-1123 was calculated after interpolating both records at 5 ka resolution using Acycle. The age models follow Elderfield et al. (2012, doi:10.1126/science.1221294) and Feng et al. (2022, doi:10.1016/j.gloplacha.2022.103945)