| Title: |
Subglacial water amplifies Antarctic contributions to sea-level rise |
| Authors: |
Zhao, Chen; Gladstone, Rupert; Zwinger, Thomas; Gillet-Chaulet, Fabien; Wang, Yu; Caillet, Justine; Mathiot, Pierre; Saraste, Leopekka; Jager, Eliot; Galton-Fenzi, Benjamin K.; Christoffersen, Poul; King, Matt A. |
| Contributors: |
Institute for Atmospheric and Earth System Research (INAR) |
| Publisher Information: |
Nature Publishing Group |
| Publication Year: |
2025 |
| Collection: |
Helsingfors Universitet: HELDA – Helsingin yliopiston digitaalinen arkisto |
| Subject Terms: |
Marine ice-sheet; Grounding-line; West antarctica; Mass-balance; Pine island; Stream-b; Slip law; Flow; Glacier; Melt; Physical sciences |
| Description: |
Antarctica's contribution to global sea-level rise is deeply uncertain, with subglacial water suspected to play a critical role, yet its impact remains unclear. We demonstrate that water at the base of ice sheets influences sliding behaviour and that its exclusion from models can underestimate sea-level rise projections and delay the predicted onset of tipping points. Here we use an Antarctic Ice Sheet model (Elmer/Ice) to explore how different assumptions about water pressure at the ice base affect sea-level rise projections from 2015 to 2300. Our results indicate that incorporating subglacial water can amplify ice discharge across the Antarctic Ice Sheet by up to threefold above the standard approach, potentially contributing an additional 2.2 metres to sea-level rise by 2300. Notably, a smoothly decreasing basal drag near the grounding line more than doubles grounding line flux by 2300 relative to scenarios where effective pressure is simplified into a spatially constant coefficient. Basin-specific responses vary significantly, with some scenarios advancing tipping points by up to 40 years. These findings underscore the critical need to integrate evolving subglacial hydrology into ice sheet models. ; Peer reviewed |
| Document Type: |
article in journal/newspaper |
| File Description: |
application/pdf |
| Language: |
English |
| Relation: |
C.Z. is the recipient of an Australian Research Council Discovery Early Career Researcher Award (project number DE240100267) funded by the Australian Government. C.Z., Y.W., P.C., and B.K.G. received grant funding from the Australian Government as part of the Antarctic Science Collaboration Initiative program (ASCI000002). R.G. was supported by the Research Council of Finland (grant numbers 322430 and 355572), and by the Finnish Ministry of Education and Culture and CSC-IT Center for Science (Decision diary number OKM/10/524/2022). T.Z. was supported by the Research Council of Finland (grant number 322978). E.J. was supported by the Research Council of Finland (grant number 355783). P.C., B.K.G. and M.A.K. are supported by the Australian Research Council Special Research Initiative, Australian Centre for Excellence in Antarctic Science (project number SR200100008). J.C. and F.G.-C. received funding from the French National Research Agency (ANR) under grants ANR-19-CE01-0015 (EIS). P.M. received funding from Agence Nationale de la Recherche-France 2030 as part of the PEPR TRACCS programme under grant number ANR-22-EXTR-0010. All simulations were enabled by computational resources provided by CSC-IT Center for Science Ltd.; https://hdl.handle.net/10138/595595; 105002978999; 001464986300018 |
| Availability: |
https://hdl.handle.net/10138/595595 |
| Rights: |
cc_by ; info:eu-repo/semantics/openAccess ; openAccess |
| Accession Number: |
edsbas.A7882370 |
| Database: |
BASE |