The Echaurren Norte Glacier, located in the Cajón del Maipo (Metropolitan Region, Chile), has lost 65% of its surface area since 1955. This has been confirmed by a study led by James McPhee, an academic at the University of Chile.
The research, published in Annals of Glaciology, documents seven decades of monitoring and reveals that today the glacier remains fragmented and covered with sediments, which alters its dynamics and makes it a critical case for understanding the impacts of the megadrought and the increase in temperatures in central Chile.
Accelerated Retreat
- In 1955, the glacier covered 0.52 km², an area larger than the surface of the Vatican.
- In 2023, only 0.18 km² remain, equivalent to 18 football fields.
- The retreat includes surface thinning, debris cover, and fragmentation into three smaller units.
- There is no longer any visible “clean ice”: the surface is covered by rocks and sediments, which modifies the energy exchange with the atmosphere.
Regional and Global Importance
Echaurren Norte is one of the only two “reference glaciers” in South America, along with Zongo in Bolivia. Its data have been fundamental for validating models on glacier mass loss and sea level rise. However, its degradation forces the need to find a new reference glacier in Chile, representative of the Southern Hemisphere.
Factors Explaining the Degradation
- Snow deficit: since 2010, the megadrought has reduced precipitation by 30%, leaving the glacier exposed to summer heat.
- Rise of the 0 °C isotherm: in 2015, 110 melting days per year were recorded; in 2020, 166 days, meaning the glacier spends almost half the year in melting conditions.
- End of climate resilience: the historical relationship with El Niño has been broken; even in rainy years, precipitation does not compensate for heat and solar radiation.
Historical Monitoring and Current Technology
The glacier has been monitored since the 1970s, initially with stakes installed on horseback or on foot. Today, satellite images, LiDAR, and aerial photographs are used to create 3D maps with millimetric precision.
This effort is a tribute to generations of Chilean scientists who have dedicated their lives to the study of glaciers, among them Cedomir Marangunic, Javier Narbona, and Jorge Quinteros.
Consequences and Concerns
The disappearance of Echaurren Norte would mean losing a key reference for understanding glacier fluctuations in the region. Additionally, it would compromise the water security of the Maipo River basin, which supplies the Metropolitan Region.
Climate change, by altering the distribution of snow reservoirs and sea conditions, poses a more unpredictable future for the glaciers of central Chile.
The study of Echaurren Norte is a clear warning: the glaciers of central Chile are at accelerated risk due to the combination of megadrought, rising temperatures, and loss of climate resilience. The need to identify a new reference glacier and strengthen monitoring is urgent to anticipate impacts on water, biodiversity, and the lives of millions of people.
