Jul 08, 2025 12:10:00

Melting glaciers could trigger volcanic eruptions around the world

One of the problems caused by global warming is the melting of

glaciers in high mountains and high latitude regions. Problems caused by melting glaciers include rising sea levels, but a new study of volcanoes and glaciers in southern Chile has found that 'melting glaciers could trigger volcanic eruptions around the world.'

Melting glaciers could trigger more explosive eruptions globally, finds research | EurekAlert!
https://www.eurekalert.org/news-releases/1089948

Melting glaciers could trigger volcanic eruptions around the globe, study finds | Live Science
https://www.livescience.com/planet-earth/volcanos/melting-glaciers-could-trigger-volcanic-erruptions-around-the-globe-study-finds

The theory that melting glaciers affect volcanic activity has been around since the 1970s. The underlying process is simple: the weight of the glaciers exerts a constant downward force on the crust and mantle. When the glaciers retreat, the weight is released, causing underground gases and magma to expand, building up pressure and causing explosive eruptions.

A 2002 study looked at glacial retreat and changes in volcanic activity in Iceland, which sits on the boundary between the North American and Eurasian plates , and showed that when the glaciers retreated at the end of the last glacial period about 10,000 years ago, the frequency of volcanic eruptions increased 30 to 50 times compared to before.

However, the relationship between glaciers and volcanoes in continental volcanic systems has not yet been fully studied. Therefore, a research team led by Pablo Moreno-Jaeger, a graduate student at the University of Wisconsin-Madison , USA, investigated the melting of the Patagonian ice sheet that occurred thousands of years ago and the response of volcanoes to the melting of volcanoes at six volcanoes, including Mocho-Choshuenco in southern Chile.

The team used the radioactive decay of

argon released by volcanic eruptions as a kind of clock, and by studying crystals formed in lava by eruptions, they tracked the relationship between volcanic activity and glacial melting.

The study found that the Patagonian ice sheet suppressed the scale of eruptions during the peak of the last glacial period, about 26,000 to 18,000 years ago, forming a huge magma chamber beneath the surface. When the ice sheet melted, the pressure in the magma chamber increased, eventually leading to the formation of the Mocho-Choshuenco volcano.

'Glaciers tend to suppress the amount of eruption from volcanoes below them, but our results suggest that as climate change causes the glaciers to retreat, these volcanoes will erupt more frequently and explosively,' Jaeger said.

A 2020 study found that 245 potentially active volcanoes are located within 5 km of the ice surface around the world, meaning that melting glaciers could lead to an increase in volcanic eruptions around the world. Jaeger and his colleagues cited North America, New Zealand, and Russia as areas of particular concern.

When a volcano erupts, the sulfate aerosols released may cause cooling in the short term by reflecting sunlight, but in the long term they are likely to accelerate global warming due to the greenhouse gases released by the eruption.

'The cumulative effects of multiple eruptions could contribute to long-term global warming due to the buildup of greenhouse gases. This could create a positive feedback loop in which melting glaciers trigger eruptions, which in turn drive further warming and glacier melt,' Jaeger said.

The research team plans to present the results of this study at the Goldschmidt International Conference on Geochemistry, which is being held in Prague, Czech Republic, in July 2025.