Preprints
https://doi.org/10.5194/egusphere-2023-2233
https://doi.org/10.5194/egusphere-2023-2233
17 Oct 2023
 | 17 Oct 2023

The influence of present-day regional surface mass balance uncertainties on the future evolution of the Antarctic Ice Sheet

Christian Wirths, Johannes Sutter, and Thomas Stocker

Abstract. Rising global sea levels are one of many impacts, the current anthropogenic global warming poses to humanity. The Antarctic Ice Sheet (AIS) has the potential to contribute several meters of sea level rise over the next few centuries. To predict future sea level rise contributions from ice sheets, both global and regional climate model (RCM) outputs are used as forcing in ice sheet model simulations. While the impact of different global models on future projections is well-studied, the impact of different regional models on the evolution of the AIS is not well-constrained. In our study, we investigated the impact of the choice of present-day reference RCM forcing on the evolution of the AIS. We used the Parallel Ice Sheet Model (PISM) to study the AIS in a constant forcing quasi-equilibrium state and under future projections, combining present-day RCM output with global climate model projections. Our study shows that the choice of RCM reference forcing results in uncertainties of future sea level rise predictions of 8.7 (7.3–9.5) cm in the year 2100 and 24.3 (16.3–46.5) cm in 2300 under the RCP8.5 scenario. Those uncertainties are of the same order of magnitude as the choice of the underlying ice sheet model parameterization and global climate model. Additionally, our study shows that the choice of RCM reference affects the extent of grounding line retreat in West Antarctica in future projections and can result in the potential long-term collapse of the West Antarctic Ice Sheet in quasi-equilibrium simulations. Our study therefore highlights the importance, of a careful choice of RCM reference forcing for simulations of the AIS.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
Christian Wirths, Johannes Sutter, and Thomas Stocker

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-2023-2233', Anonymous Referee #1, 17 Nov 2023
    • AC1: 'Reply on RC1', Christian Wirths, 29 Feb 2024
  • RC2: 'Comment on egusphere-2023-2233', Christoph Kittel, 07 Dec 2023
    • AC2: 'Reply on RC2', Christian Wirths, 29 Feb 2024
  • RC3: 'Comment on egusphere-2023-2233', Anonymous Referee #3, 12 Dec 2023
    • AC3: 'Reply on RC3', Christian Wirths, 29 Feb 2024
Christian Wirths, Johannes Sutter, and Thomas Stocker
Christian Wirths, Johannes Sutter, and Thomas Stocker

Viewed

Total article views: 651 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
414 206 31 651 22 20
  • HTML: 414
  • PDF: 206
  • XML: 31
  • Total: 651
  • BibTeX: 22
  • EndNote: 20
Views and downloads (calculated since 17 Oct 2023)
Cumulative views and downloads (calculated since 17 Oct 2023)

Viewed (geographical distribution)

Total article views: 625 (including HTML, PDF, and XML) Thereof 625 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 26 May 2024
Download
Short summary
We investigated the influence of several regional climate models onto the Antarctic Ice Sheet, when applied as forcing for the Parallel Ice Sheet Model (PISM). Our study shows, that the choice of regional climate model forcing results in uncertainties similar to the ones in future sea level rise projections and affects also the extent of grounding line retreat in West Antarctica.