Antarctic Ice‐Core Water ( USGS49) – A New Isotopic Reference Material for δ 2 H and δ 18 O Measurements of Water

• Published in: Geostandards and Geoanalytical Research
• Main Authors: Lorenz, Jennifer M., Qi, Haiping, Coplen, Tyler B.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2016
• Subjects: Amundsen Scott South Pole Station; Amundsen-Scott; Amundsen-Scott South Pole Station; Antarctic; South Pole; Antarc*; ice core; South pole
• Online Access: http://dx.doi.org/10.1111/ggr.12135; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fggr.12135; https://onlinelibrary.wiley.com/doi/pdf/10.1111/ggr.12135

As a result of the scarcity of isotopic reference waters for daily use, a new secondary isotopic reference material for international distribution has been prepared from ice‐core water from the Amundsen–Scott South Pole Station. This isotopic reference material, designated as USGS 49, was filtered, homogenised, loaded into glass ampoules, sealed with a torch, autoclaved to eliminate biological activity and measured by dual‐inlet isotope‐ratio mass spectrometry. The δ 2 H and δ 18 O values of USGS 49 are −394.7 ± 0.4 and −50.55 ± 0.04 mUr (where mUr = 0.001 = ‰), respectively, relative to VSMOW , on scales normalised such that the δ 2 H and δ 18 O values of SLAP reference water are, respectively, −428 and −55.5 mUr. Each uncertainty is an estimated expanded uncertainty ( U = 2 u c ) about the reference value that provides an interval that has about a 95% probability of encompassing the true value. This isotopic reference material is intended as one of two isotopic reference waters for daily normalisation of stable hydrogen and oxygen isotopic analysis of water with an isotope‐ratio mass spectrometer or a laser absorption spectrometer. It is available by the case of 144 glass ampoules or as a set of sixteen glass ampoules containing 5 ml of water in each ampoule.