Response of Water Isotopes in Precipitation to a Collapse of the West Antarctic Ice Sheet in High-Resolution Simulations with the Weather Research and Forecasting Model

Author(s)
Marina Dütsch, Eric J. Steig, Peter N. Blossey, Andrew G. Pauling
Abstract

The West Antarctic Ice Sheet (WAIS) may have collapsed during the last interglacial period, between 132 000 and 116 000 years ago. The changes in topography resulting from WAIS collapse would be accompanied by significant changes in Antarctic surface climate, atmospheric circulation, and ocean conditions. Evidence of these changes may be recorded in water-isotope ratios in precipitation archived in the ice. We conduct high-resolution simulations with an isotope-enabled version of the Weather Research and Forecasting Model over Antarctica, with boundary conditions provided by climate model simulations with both present-day and lowered WAIS topography. The results show that while there is significant spatial variability, WAIS collapse would cause detectable isotopic changes at several locations where icecore records have been obtained or could be obtained in the future. The most robust signals include elevated δ18O at SkyTrain Ice Rise in West Antarctica and elevated deuterium excess and δ18O at Hercules Dome in East Antarctica. A combination of records from multiple sites would provide constraints on the timing, rate, and magnitude of pastWAIS collapse.

Organisation(s)
Department of Meteorology and Geophysics
External organisation(s)
University of Washington
Journal
Journal of Climate
Volume
36
Pages
5417-5430
No. of pages
14
ISSN
0894-8755
DOI
https://doi.org/10.1175/JCLI-D-22-0647.1
Publication date
08-2023
Peer reviewed
Yes
Austrian Fields of Science 2012
105204 Climatology, 105205 Climate change
Keywords
ASJC Scopus subject areas
Atmospheric Science
Sustainable Development Goals
SDG 13 - Climate Action
Portal url
https://ucrisportal.univie.ac.at/en/publications/32da0ddd-e428-4b9a-aba2-10c79ad295f3