Filchner Ice Shelf cavity noble gas (helium and neon) measurements ...

• Main Authors: Huhn, Oliver, Hattermann, Tore, Davis, Peter, Dunker, Erich, Hellmer, Hartmut H, Nicholls, Keith W, Østerhus, Svein, Rhein, Monika, Schröder, Michael, Sültenfuß, Jürgen
• Format: Dataset
• Language: English
• Published: PANGAEA 2017
• Subjects: Event label; Sample ID; Date/Time of event; Latitude of event; Longitude of event; Helium-4; Neon; Helium-3; δ Helium-3; Salinity; Temperature, water, potential; Pressure, water; DEPTH, water; Distance; Pressure, total; Ice thickness; Freeboard; CTD/Rosette; CTD; ANT-Land_2016/17_FISP; ANT-Land_2015/16_FISP; AWI Antarctic Land Expedition; Priority Programme 1158 Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas SPP1158; Antarctic; Arctic; Filchner Ice Shelf; Antarc*; Ice Shelf; Sea ice
• Online Access: https://dx.doi.org/10.1594/pangaea.883808; https://doi.pangaea.de/10.1594/PANGAEA.883808

To obtain noble gas samples from the water column below an ice shelf, we have constructed a new gas-tight in-situ water sampler to prevent the water samples from the sub-glacial cavity from gas-fractionation and degassing due to freezing and expansion. The novel instrument contains a degreased soft copper tube (diameter 10 mm, length 90 cm) allowing a sea-water sample of ~44 g as usually used for oceanic noble gas samples. Both ends are connected with high pressure ball valves with gas-tight swagelok© connectors to it at both ends. Additional intake and outtake funnels extend the tube at both ends of the sampling device to increase the water flux for flushing and rinsing the copper tube. The instrument is mounted in an aluminum cylinder (diameter 100 mm, length 1510 mm, weight 8 kg) to protect it while it is moved through the bore hole (diameter approx. 250 mm). The instrument is lowered through the bore hole into the water underneath the ice shelf on a 3.25 mm wire together with a CTD measuring continuously ...