Glacier retreat could drive a surge in volcanic eruptions worldwide

Glacier retreat could drive a surge in volcanic eruptions worldwide
by Clarence Oxford
Los Angeles CA (SPX) Jul 08, 2025

Melting glaciers may be laying the groundwork for more explosive and frequent volcanic eruptions, according to new research presented at the Goldschmidt Conference in Prague. The study focuses on six volcanoes in the southern Chilean Andes and suggests that similar dynamics could be at play in hundreds of subglacial volcanoes worldwide, particularly in Antarctica.

The research team, led by scientists from the University of Wisconsin-Madison and supported by collaborators at Lehigh University, UCLA, and Dickinson College, used argon dating and crystal analysis to examine how the growth and retreat of the Patagonian Ice Sheet influenced past volcanic activity. Volcanoes like Mocho-Choshuenco, now dormant, revealed evidence of dramatic changes linked to glacial movements.

Data show that during the last ice age, heavy glacial ice suppressed volcanic eruptions while allowing pressurized, silica-rich magma to accumulate deep underground. When the ice melted rapidly between 26,000 and 18,000 years ago, the release of pressure allowed volcanic gases to expand, driving explosive eruptions that shaped the modern volcanoes.

"Glaciers tend to suppress the volume of eruptions from the volcanoes beneath them. But as glaciers retreat due to climate change, our findings suggest these volcanoes go on to erupt more frequently and more explosively," said Pablo Moreno-Yaeger from UW-Madison, who presented the research. "The key requirement for increased explosivity is initially having a very thick glacial coverage over a magma chamber, and the trigger point is when these glaciers start to retreat, releasing pressure - which is currently happening in places like Antarctica."

Although this glacial-volcanic link has been known in Iceland for decades, the new study highlights similar potential in continental regions including North America, New Zealand, and Russia. The findings suggest these areas deserve increased monitoring as global temperatures rise.

While geological reactions can seem sudden, Moreno-Yaeger emphasized that changes in magma systems develop over centuries, allowing time for improved surveillance and early warning systems.

The study also warns that volcanic eruptions triggered by melting glaciers could feed back into climate change. Short-term cooling from aerosols, as seen after Mount Pinatubo's 1991 eruption, may be offset by the long-term warming effects of greenhouse gas emissions from repeated eruptions.

"Over time the cumulative effect of multiple eruptions can contribute to long-term global warming because of a buildup of greenhouse gases," Moreno-Yaeger said. "This creates a positive feedback loop, where melting glaciers trigger eruptions, and the eruptions in turn could contribute to further warming and melting."

The research is supported by a National Science Foundation grant led by UW-Madison's Professor Brad Singer and is expected to be published in a peer-reviewed journal later this year.