Ayala et al. (2025) Less water from glaciers during future megadroughts in the Southern Andes

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Repository for Publications and Research Data (ETH Zurich)
• Year: 2025
• Date: 2025-11-18
• Authors: Ayala, Álvaro, Muñoz-Castro, Eduardo, Farinotti, Daniel, Farías-Barahona, David, Mendoza, Pablo A., MacDonell, Shelley, McPhee, James, Vargas, Ximena, Pellicciotti, Francesca
• DOI: 10.3929/ethz-c-000788141

Research Groups

Not explicitly mentioned in the provided text.

Short Summary

This study assesses the response of Southern Andes glaciers to current and projected megadroughts, revealing that while recent droughts were buffered by significant ice loss, future megadroughts will severely diminish glacier runoff, exacerbating water scarcity.

Objective

• To assess the response of glaciers in the Southern Andes to the severe, persistent, and extensive drought from 2010 to the present, and to projected end-of-century megadroughts.

Study Configuration

• Spatial Scale: Southern Andes
• Temporal Scale: 2000-2009 (baseline), 2010-2019 (current drought), end-of-century (projected megadroughts)

Methodology and Data

• Models used: Glacio-hydrological numerical simulations
• Data sources: Not explicitly mentioned, but likely includes climate model outputs for projections and observational data for current conditions and model calibration.

Main Results

• During the 2010-2019 drought, despite a mean annual precipitation deficit of 36% compared to 2000-2009, glacier runoff remained almost unaltered.
• This sustained runoff was achieved through a 10% loss of total ice volume during the 2010-2019 period.
• Simulations project that annual glacier runoff could decline by up to 20 ± 11% during end-of-century megadroughts compared to pre-2010 levels.
• Summer glacier runoff is projected to decline even more significantly, by up to 48 ± 6%, during end-of-century megadroughts compared to pre-2010 levels.
• These results indicate a weakening of the glacier's buffering role against precipitation deficits during extreme droughts, leading to increased water scarcity for ecosystems and livelihoods.

Contributions

• Quantifies the current and future buffering capacity of Southern Andes glaciers against extreme droughts.
• Provides projections of significant reductions in glacier runoff under end-of-century megadrought scenarios.
• Highlights the critical implications for water security and scarcity in mountain regions of South America.

Funding

Not explicitly mentioned in the provided text.

Citation

@article{Ayala2025Less,
  author = {Ayala, Álvaro and Muñoz-Castro, Eduardo and Farinotti, Daniel and Farías-Barahona, David and Mendoza, Pablo A. and MacDonell, Shelley and McPhee, James and Vargas, Ximena and Pellicciotti, Francesca},
  title = {Less water from glaciers during future megadroughts in the Southern Andes},
  journal = {Repository for Publications and Research Data (ETH Zurich)},
  year = {2025},
  doi = {10.3929/ethz-c-000788141},
  url = {https://doi.org/10.3929/ethz-c-000788141}
}