25 Apr 2022
25 Apr 2022

Improving continuous-flow analysis of triple oxygen isotopes in ice cores: insights from replicate measurements

Lindsey Davidge, Eric J. Steig, and Andrew J. Schauer Lindsey Davidge et al.
  • Department of Earth and Space Science, University of Washington, Seattle, 98195, USA

Abstract. Stable water isotope measurements from polar ice cores provide high-resolution information about past hydrologic conditions and are therefore important to understanding Earth's climate system. Routine high-resolution measurements of δ18O, δD, and deuterium excess are made by continuous-flow analysis (CFA) methods that include laser spectroscopy instruments. Recent advances in instrumentation allow for simultaneous measurements of all stable water isotopes, including δ17O and 17O excess (Δ17O). Here, we present replicate measurements of an ice core sample taken from Summit, Greenland, using a CFA system coupled to a cavity ring-down laser spectroscopy (CRDS) instrument. We demonstrate that our CFA-CRDS method can make high-precision measurements of Δ17O (< 5 per meg) with high resolution (a few cm) in ice core samples. We find that calibration errors generate most of the variability among the replicate datasets. Our work shows that CFA-CRDS methods can detect seasonal variability in Δ17O. We suggest that CFA-CRDS methods should be applied to ice core measurements when high-resolution information is desired.

Lindsey Davidge et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2022-60', Anonymous Referee #1, 15 May 2022
    • AC1: 'Reply on RC1', Lindsey Davidge, 15 Jul 2022
  • RC2: 'Comment on egusphere-2022-60', Anonymous Referee #2, 17 May 2022
    • AC2: 'Reply on RC2', Lindsey Davidge, 15 Jul 2022

Lindsey Davidge et al.

Lindsey Davidge et al.


Total article views: 367 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
303 58 6 367 3 3
  • HTML: 303
  • PDF: 58
  • XML: 6
  • Total: 367
  • BibTeX: 3
  • EndNote: 3
Views and downloads (calculated since 25 Apr 2022)
Cumulative views and downloads (calculated since 25 Apr 2022)

Viewed (geographical distribution)

Total article views: 316 (including HTML, PDF, and XML) Thereof 316 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 29 Sep 2022
Short summary
We describe a continuous flow method to measure Δ17O by laser spectroscopy, and we show that cm-scale information can be measured reliably in ice cores by this method. We present seasonally resolved measurements of Δ17O from Greenland, and we demonstrate that – though small – most of our remaining error is from calibration. Our results reinforce the use of this method for high-precision, high-resolution measurements of Δ17O; they also identify calibration as a limiting step for this method.