Researchers have identified a significant deposit of tropical permafrost beneath the upper flanks of Peru’s Nevado Coropuna, a discovery that could provide a critical, long-term water source for arid high-altitude regions. Published in Permafrost and Periglacial Processes, the study confirms a 15-to-20-meter thick layer of frozen ground located approximately 5,000 meters above sea level, offering a potential buffer as regional glaciers continue to recede due to climate change.
Where is the permafrost located?
The permafrost discovery is centered on the upper slopes of Nevado Coropuna, one of the tallest volcanoes in Peru. Geographer Ramón Pellitero of the National University of Distance Education in Madrid and his research team utilized ground-penetrating radar and vertical electrical sounding to confirm the presence of the frozen layer. The team found that the permafrost sits roughly two to four meters below the surface. Because the team had to manually transport heavy equipment across the harsh, remote terrain at elevations exceeding 5,000 meters, the area has historically lacked the detailed scientific mapping seen in lower-altitude or more accessible regions.
Why does this matter for local water security?
Local communities in the Peruvian Andes currently rely on glacial melt to sustain agriculture and domestic needs. However, these glaciers are retreating at an accelerated rate under current climate warming trends. According to Pellitero, the newly identified permafrost acts as a stable, subterranean water reservoir. As the climate warms, this frozen ground may thaw, potentially releasing stored water that could sustain local ecosystems and human populations even after surface glaciers disappear. While this reservoir is not as expansive as the massive permafrost zones found in Russia or Canada, its presence is vital for the arid climate of the Andes.
How does tropical permafrost compare globally?
Tropical permafrost is rare and typically found in isolated, high-altitude patches. Other known sites include Mount Kilimanjaro in Tanzania and Mauna Kea in Hawaii. Monitoring data from Mauna Kea shows that its permafrost patch has undergone significant decline, shrinking from approximately 600 square meters in the 1970s to roughly 200 square meters by the mid-2010s. The Peruvian site represents a much larger, more stable formation than these examples. Researchers, including geographer Stephan Gruber of Carleton University, note that the interaction between high-altitude permafrost, mountain hydrology, and local hazards remains an under-researched field that requires further investigation.
What are the next steps for research?
The research team is currently planning to expand their mapping efforts using electric resistivity tomography, a technique that provides high-resolution subterranean imaging. This will allow scientists to determine the precise geographic extent of the permafrost around Nevado Coropuna. While the researchers suspect that similar frozen layers exist elsewhere in the region at the 5,000-meter elevation mark, current data is limited to the immediate vicinity of their initial study site. Future field seasons aim to confirm whether this "hidden" water source is a localized phenomenon or a widespread feature of the high-altitude Andes.
Key Facts About the Peruvian Permafrost
- Depth: The permafrost layer is 15 to 20 meters thick.
- Elevation: The findings are located at approximately 5,000 meters above sea level.
- Detection Method: Researchers used ground-penetrating radar and electrical resistance measurements to identify the ice.
- Significance: It serves as a potential long-term water source for communities facing glacial retreat.