Tricht et al. (2025) Peak glacier extinction in the mid-twenty-first century

Identification

• Journal: Nature Climate Change
• Year: 2025
• Date: 2025-12-15
• Authors: Lander Van Tricht, Harry Zekollari, Matthias Huss, David R. Rounce, Lilian Schuster, Rodrigo Aguayo, Patrick Schmitt, Fabien Maussion, B. S. Tober, Daniel Farinotti
• DOI: 10.1038/s41558-025-02513-9

Research Groups

• Laboratory of Hydraulics, Hydrology and Glaciology (VAW), ETH Zürich, Zurich, Switzerland
• Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Sion, Switzerland
• Department of Water and Climate, Vrije Universiteit Brussel, Brussels, Belgium
• Department of Geosciences, University of Fribourg, Fribourg, Switzerland
• Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
• Department of Atmospheric and Cryospheric Sciences (ACINN), Universität Innsbruck, Innsbruck, Austria
• Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, UK

Short Summary

This study projects the future disappearance of over 200,000 individual glaciers globally under various warming scenarios, revealing a peak extinction period between 2041 and 2055 where up to 4,000 glaciers could vanish annually. It introduces the concept of "peak glacier extinction" to highlight the societal and cultural implications of individual glacier loss.

Objective

• To quantify the disappearance of individual glaciers worldwide and identify the timing and magnitude of "peak glacier extinction" under different global warming scenarios (+1.5 °C, +2.0 °C, +2.7 °C, +4.0 °C relative to pre-industrial levels) by 2100.

Study Configuration

• Spatial Scale: Global, with detailed regional analysis across 19 regions (e.g., High-mountain Asia, European Alps, Arctic, Andes).
• Temporal Scale: Projections from 2025 to 2100, based on a glacier inventory from approximately 2000.

Methodology and Data

• Models used: Global Glacier Evolution Model (GloGEM), Open Global Glacier Model (OGGM), Python Glacier Evolution Model (PyGEM).
• Data sources:
  • Glacier inventory: Randolph Glacier Inventory version 6.0 (RGI v.6.0), comprising over 200,000 glaciers.
  • Climate forcing: Climate projections from Shared Socioeconomic Pathways (SSPs) for General Circulation Models (GCMs) of the Coupled Model Intercomparison Project Phase 6 (CMIP6).
  • Glacier disappearance criteria: A glacier is classified as disappeared when its projected area falls below 0.01 square kilometers or its remaining volume declines to less than 1% of its initial value.

Main Results

• Global peak glacier extinction is projected to occur between 2041 and 2055, with the timing and magnitude dependent on the warming level.
• Under a +1.5 °C warming scenario, global peak glacier extinction is projected to reach approximately 2,000 glaciers per year around 2041.
• Under a +4.0 °C warming scenario, the peak shifts to the mid-2050s and intensifies to approximately 4,000 glaciers per year.
• This peak rate of 2,000 to 4,000 glaciers per year is three to five times higher than the present-day modelled global loss of 750–800 glaciers annually.
• Regional variability is significant: regions with small, rapidly responding glaciers (e.g., Caucasus, European Alps) show early peaks (before or around 2040), while regions with larger glaciers (e.g., Greenland Periphery, Svalbard) exhibit delayed peaks.
• By 2100, under +1.5 °C warming, nearly 50% of today's glaciers may remain.
• Under current policy pledges (+2.7 °C), only approximately 20% of the initial glacier count is projected to remain by 2100.
• Under +4.0 °C warming, fewer than 10% of present-day glaciers (less than 20,000) are projected to survive by 2100, with many regions becoming nearly glacier-free.

Contributions

• Introduces and quantifies the novel concept of "peak glacier extinction," providing a number-based metric that complements traditional measures of glacier mass and area loss.
• Highlights the profound societal, cultural, and touristic implications of individual glacier disappearance, reframing glacier loss as a human story.
• Provides comprehensive global and regional projections of individual glacier disappearance under policy-relevant warming scenarios, offering a critical timeline for climate action.
• Demonstrates quantitatively that ambitious climate policy, particularly limiting warming to +1.5 °C, could more than double the number of glaciers surviving by 2100 compared to higher warming pathways.

Funding

• Research Foundation—Flanders (Odysseus Type II project, grant no. G0DCA23N; ‘GlaciersMD’ project)
• European Research Council (Horizon Framework research and innovation programme, grant no. 101115565; ‘ICE3’ project)
• European Union’s Horizon 2020 research and innovation programme (PROTECT project; grant no. 869304)
• National Aeronautics and Space Administration (grant nos 80NSSC20K1296 and 80NSSC20K1595)
• National Park Service (grant no. P22AC02208)
• Austrian Academy of Sciences (DOC Fellowship, no. 25928)
• European Union’s Horizon 2020 research and innovation programme (grant agreement no. 101003687)
• Austrian Climate Research Programme—14th call (grant agreement no. KR21KB0K00001; HyMELT-CC)
• ESA’s ‘Digital Twin Component for Glaciers’ project (grant no. 4000146160/24/I-KE)
• Open access funding provided by Swiss Federal Institute of Technology Zurich.

Citation

@article{Tricht2025Peak,
  author = {Tricht, Lander Van and Zekollari, Harry and Huss, Matthias and Rounce, David R. and Schuster, Lilian and Aguayo, Rodrigo and Schmitt, Patrick and Maussion, Fabien and Tober, B. S. and Farinotti, Daniel},
  title = {Peak glacier extinction in the mid-twenty-first century},
  journal = {Nature Climate Change},
  year = {2025},
  doi = {10.1038/s41558-025-02513-9},
  url = {https://doi.org/10.1038/s41558-025-02513-9}
}