Trace gas measurements, basal glacial meltwater fractions, and water ages during RV POLARSTERN cruise PS124, Southern Weddell Sea, 2021 ...

• Main Authors: Huhn, Oliver, Janout, Markus A, Sültenfuß, Jürgen, Bulsiewicz, Klaus, Hinse, Yannik
• Format: Dataset
• Language: unknown
• Published: PANGAEA 2024
• Subjects: age dating; CFC12; glacial mel water fractions; He; Helium; melt water; Ne; NEON; noble gas; SF6; water mass ages; Event label; Elevation of event; Station label; Cast number; Bottle number; Pressure, water; LATITUDE; LONGITUDE; Temperature, water, potential; Salinity; Quality flag; Helium, excess above solubility equilibrium; δ Helium-3; Neon; Neon, excess above solubility equilibrium; Deviation from equilibrium He/Ne ratio; Glacial meltwater; Freon-12 dichlorodifluoromethane; Sulfur hexafluoride, SF6; Age; Transient time distribution mean age; CTD/Rosette; see references; Age, calculated from CFC/SF6 ratio; PS124; Polarstern; Weddell; Weddell Sea
• Online Access: https://dx.doi.org/10.1594/pangaea.971321; https://doi.pangaea.de/10.1594/PANGAEA.971321

In this data set we present trace gas measurements and derived variables such as basal glacial meltwater (GMW) fractions and water ages. The trace gases comprise the lighter noble gasses, i.e., total helium (He) and the excess above solubility equilibrium ΔHe, the 3He/4He ratio reported as δ3He, total neon (Ne) and the excess ΔNe, and the deviation from the equilibrium He/Ne ratio Δ(He/Ne), as well as the transient anthropogenic trace gases chlorofluorocarbon (CFC-12) and sulphur hexafluoride (SF6) concentrations. From these noble gases He and Ne we derived glacial meltwater fractions. From the transient tracers we computed SF6-concentration ages, CFC-12/SF6 ratio ages and TTD mean ages. ... : Hydrographic data:The hydrographic data were adopted from Tippenhauer et al., 2023.Noble gases:Water samples were taken from the CTD/water bottle systems without contact to atmospheric air into 40 ml gas tight copper tubes, which are clamped of at both sides.In the IUP Bremen noble gas lab the samples were pre-processed with a UHV (ultra-high vacuum) gas extraction system. Sample gases are transferred via water vapour into a glass ampoule kept at liquid nitrogen temperature. For analysis of the noble gas isotopes the glass ampoules are connected to a fully automated UHV mass spectrometric system equipped with a two-stage cryogenic system, a quadrupole and a sector-field mass spectrometer. Regularly, the system is calibrated with atmospheric air standards (reproducibility < 0.2%). Measurement of line blanks and linearity are done as well. The performance of the Bremen facility is described in Sültenfuß et al. (2009).Noble gas concentrations are reported in nmol/kg for He and Ne and are additionally ...