Medina et al. (2026) A comprehensive rock glacier inventory for the Peruvian Andes (PRoGI): dataset, characterization and topoclimatic attributes

Identification

• Journal: Earth system science data
• Year: 2026
• Date: 2026-01-14
• Authors: Katy Medina, Hairo León, Edwin Badillo-Rivera, Edwin C. Loarte, José Úbeda
• DOI: 10.5194/essd-18-345-2026

Research Groups

• Research Center for Environmental Earth Science and Technology (ESAT), Santiago Antunez de Mayolo National University (UNASAM), Huaraz, Peru
• Faculty of Environmental Sciences, Santiago Antunez de Mayolo National University (UNASAM), Huaraz, Peru
• Departamento de Geografía, Universidad Complutense de Madrid, Madrid, Spain
• Faculty of Environmental Engineering and Natural Resources, National University of Callao, Bellavista, Peru
• Research Center Climate Change and Disaster Risk Management, National University of Callao, Bellavista, Peru
• Laboratoire EDYTEM, Université Savoie Mont Blanc, CNRS, Le Bourget-du-Lac, France
• Departamento de Ciencias de la Tierra, Guías de Espeleología y Montaña, Torremocha de Jarama, Spain

Short Summary

This study presents the first comprehensive inventory of rock glaciers for the entire Peruvian Andes (PRoGI v1.0), identifying 2338 landforms with a total area of 94.09 square kilometers. The inventory characterizes their spatial distribution, morphological attributes, and topoclimatic controls, revealing a concentration in the southern, drier Andes at high elevations and predominantly south-facing aspects.

Objective

• To create a comprehensive, national-scale inventory of rock glaciers for the Peruvian Andes, documenting their spatial distribution, morphological attributes, and topoclimatic controls using standardized methods.

Study Configuration

• Spatial Scale: Entire Peruvian Andes (approximately 4 to 18° S and 80 to 69° W), covering an area of approximately 308,124 square kilometers.
• Temporal Scale: Satellite imagery primarily from 2017 to 2025 (Bing Maps 2024, Google Earth 2017); climate data for 1979–2013; permafrost model data for 2000–2016.

Methodology and Data

• Models used: CHELSA 2.1 climate dataset (for Mean Annual Air Temperature and Annual Precipitation), Obu et al. (2019) Mean Annual Ground Temperature model.
• Data sources: High-resolution satellite imagery (Bing Maps Aerial, Google Satellite), 12.5-meter resolution ALOS PALSAR Digital Elevation Model (DEM), National Inventory of Glaciers and Glacial Lakes (INGLOG II) of Peru.
• Mapping Protocol: Manual digitization of rock glacier polygons following International Permafrost Association (IPA) Action Group on Rock Glacier Inventories and Kinematics (RGIK) guidelines, using a simplified three-class activity system (active, transitional, relict). Grid-based systematic mapping (50 km x 50 km cells) with rigorous quality control and consensus-based activity classification.

Main Results

• A total of 2338 rock glaciers were identified, covering a total area of 94.09 ± 0.05 square kilometers.
• Approximately 31% were classified as active, 49% as transitional, and 20% as relict.
• Rock glaciers predominantly occur between approximately 4416 and 5783 meters above sea level (mean elevation approximately 4999 meters) on slopes averaging approximately 20.7 degrees (range 7–37 degrees).
• Spatially, rock glaciers are concentrated in the Southern Dry Outer Tropics (SDOT) subregion, with significantly higher density (1.98 per 100 square kilometers) and area coverage (0.08%) compared to northern and wetter subregions.
• Most rock glaciers have a southern to southwestern aspect (predominantly S, SW, and SE-facing).
• The lower limit of permafrost, indicated by the lowest active rock glacier fronts, is approximately 3541 meters above sea level.
• Mean Annual Air Temperature (MAAT) for rock glaciers ranges from -2 to 4 °C, with active forms occurring under the coldest conditions (mean MAAT 1.08 °C).
• Mapping uncertainty for individual rock glacier area averaged approximately 18%, with high inter-mapper agreement (Intraclass Correlation Coefficients > 0.95 for key attributes).

Contributions

• Provides the first comprehensive, national-scale rock glacier inventory for the Peruvian Andes, filling a significant data gap in tropical South America.
• Establishes a standardized baseline dataset (PRoGI v1.0) using IPA guidelines, enabling interoperability with global permafrost monitoring networks.
• Offers crucial insights into the distribution, morphology, and topoclimatic controls of mountain permafrost in a tropical environment, highlighting the importance of cold, arid conditions and specific lithologies.
• Serves as a benchmark for future monitoring of permafrost changes and supports applied research in water resource management, hydrological modeling, and natural hazard assessment for Peruvian environmental authorities.

Funding

• Project "Permafrost: rock walls and rock glaciers as water regulators and risk generators in Peru in a context of climate change (PermaPeru)" (Contract no. PE501089264-2024-PROCIENCIA), funded by CONCYTEC-PROCIENCIA.
• Research Center for Environmental Earth Science and Technology (ESAT) of the Universidad Nacional Santiago Antúnez de Mayolo (UNASAM), through its Mountain Ecosystems and Permafrost Research Group (PAMEC).

Citation

@article{Medina2026comprehensive,
  author = {Medina, Katy and León, Hairo and Badillo-Rivera, Edwin and Loarte, Edwin C. and Bodín, Xavier and Úbeda, José},
  title = {A comprehensive rock glacier inventory for the Peruvian Andes (PRoGI): dataset, characterization and topoclimatic attributes},
  journal = {Earth system science data},
  year = {2026},
  doi = {10.5194/essd-18-345-2026},
  url = {https://doi.org/10.5194/essd-18-345-2026}
}