The glaciers of the tropical Andes have shrunk by 42% since 1990, according to a study

According to the research, climate change and the increase in  burning in the Amazon  are among the causes of the loss of almost half of the surface of the tropical Andean glaciers in the last 30 years.


Tropical Andean glaciers are experiencing a rapid reduction, with potential environmental, cultural and economic impacts for local populations, warns an investigation carried out by specialists from the MapBiomas Amazonia initiative in collaboration with the La Molina National Agrarian University, the Glacier Research Institute and Mountain Ecosystems, both from Peru, and the National Institute for Space Research, from Brazil.

The study published in the journal Remote Sensing indicates that between 1990 and 2020, the loss of 42% of the coverage of tropical Andean glaciers was recorded, from a maximum of 2,429.38 km2 to just 1,409.11 km2. The retreat registered in the last three decades is equivalent to almost half of the extension of the tropical Andean glaciers registered in 1990.

Experts indicate that this unprecedented increase in the loss of glaciers, both in extension and volume, can be attributed mainly to climate change  and non-climatic factors such as the increase in recent years of forest burning in the Amazon , which generates black carbon. , which can accelerate the retreat of glaciers by coming into contact with the surface of the glaciers.

“The burning of forests generates black carbon, which accelerates the retreat of glaciers when it comes into contact with the surface of the glacier,” explains Efrain Turpo, who led the study. In addition, he highlights that the loss of glaciers affects the integrity of ecosystems that depend on the water cycle, agriculture, drinking water supply, electricity generation, tourism, among others.

For her part, María Olga Borja, co-author of the article, underlines the importance of reducing emissions that originate in the destruction of forests to give way to other uses of the land, such as agriculture and livestock .

The research highlights the urgency for national governments to take decisive action to combat the climate crisis, including climate change adaptation policies and programs, including climate change adaptation policies and programs, particularly in glacial basins, in order to reduce the impacts of deglaciation.

The tropical Andean glaciers are located between the Tropic of Cancer and the Tropic of Capricorn (between latitudes 23◦N and 23◦S) within the Intertropical Convergence Zone (ITCZ). The pace of change is fast, with an average annual loss of 28.42 km2. The most affected, the article warns, have been the glaciers that are below 5,000 meters above sea level, which in 30 years have lost almost 80.25% of their area. The acceleration was more significant after 1995, when the loss in the Amazon Basin exceeded that in other basins. In 2020 they had an approximate area of ​​869.59 km2.

By covering the entire tropical Andes and 36 years of annual mapping, the recent MapBiomas study can be considered the most comprehensive currently available, according to Raúl Espinoza, co-author of the study.

What are the most affected South American countries?

Tropical Andean glaciers are present, with very varied extensions, in all the Andean countries. Those with the largest glacier areas are Peru (72.76%), Bolivia (20.35%) and Ecuador (3.89%). The largest glacier areas, 44.75% of the total, occur in a strip between –14° and −10° latitude, which contains the Peruvian Cordilleras Blanca, Vilcanota, Vilcabamba and Urubamba. In these countries, the retreat of the glaciers in 2020 in relation to 1990 was 41.19% in Peru, 42.61% in Bolivia and 36.37% in Ecuador.

Colombia, Chile and Argentina jointly account for 6.89% of the coverage of tropical Andean glaciers (3.89%, 2.18%, 0.78% and 0.04%, respectively). Venezuela has a percentage of less than 0.01%, or about 0.03 km2. Despite this, it had a coverage loss of 96.93% between 1990 and 2020. In Colombia, that percentage was 60.19%; in Chile, 47.24%; and in Argentina, 45.47%.

In addition to the environmental and economic impacts, the retreat of the glaciers causes the loss of cultural assets, since the snow-capped mountains are of special value to local populations. “The populations of the Andean countries still live today a unique symbiosis between the telluric, the psychic and the natural, so that their snowy mountains along the Andes Mountains have formed part of their worldview, involving myths, legends and ancestral social and cultural practices that survive, so the loss of the glaciers represents an impact on their daily material and symbolic life”, points out Raúl Borja Núñez, an Ecuadorian sociologist.