A new study published in the journal Geochemistry, Geophysics, Geosystems revealed a potential "ticking time bomb" beneath the West Antarctic Ice Sheet, raising alarms about the future of global sea levels. Researchers detected over 100 volcanoes beneath the Antarctic ice, located along an active volcanic rift system known as the West Antarctic Rift System, which has been active since the age of dinosaurs.
Scientists warned that as climate change accelerates the melting of the Antarctic ice sheet, the immense weight of the ice—which acts like a cork suppressing magma chambers—diminishes. This reduction in pressure allows magma to expand, exerting stress on the walls of volcanic chambers and increasing the likelihood of eruptions. The study emphasizes: "The ice sheet is melting, allowing magma to expand and increase pressure in the volcanic chambers. Carbon dioxide and water dissolved in the magma will also form gas bubbles, further increasing pressure and ultimately causing eruptions."
Researchers from Brown University conducted over 4,000 computer simulations to model this phenomenon. Their findings suggested that surface melting accelerates processes leading to volcanic eruptions by decades to hundreds of years. In one scenario, the team simulated the removal of an ice layer 1,000 meters thick over 300 years—a rate considered moderate for West Antarctica—and found an increase in volcanic activity and the size of eruptions.
The expansion of magma chambers beneath the thinning ice sheet alters pressure dynamics and accelerates processes that lead to eruptions due to the formation of gas bubbles from dissolved carbon dioxide and water in the magma. This creates a dangerous feedback loop: as ice melts, volcanic activity increases, which in turn accelerates the melting of the ice.
While increased eruptions from these hidden volcanoes would not directly harm human communities, as Antarctica is largely uninhabited, the indirect effects could be catastrophic. Volcanic eruptions release additional heat, lava, and ash, which warm the ice sheet from below and above, potentially melting millions of cubic meters of ice annually. This accelerated melting could contribute to global sea level rise, threatening coastal communities worldwide.
Current estimates indicate a near-total collapse of the West Antarctic Ice Sheet by the year 2300, giving humanity approximately 275 years to mitigate its deterioration amid increasing volcanic activity. However, the feedback loop between melting and volcanism could accelerate this timeline. The slow nature of this process means its effects could persist even if human-induced climate change slows, potentially impacting volcanic activity for thousands of years.
The potential impact of this scenario is immense. If the West Antarctic Ice Sheet were to collapse completely, sea levels could rise by about 58 meters, submerging major coastal cities such as New York, Tokyo, and Shanghai. This would render them uninhabitable and could force billions of people to migrate to safer areas.
The scientists have drawn parallels between their findings and historical data from the Andes Mountains of South America. Researchers identified a relationship between the melting of the Patagonian ice sheet during the Last Glacial Maximum and increased activity in volcanoes such as Calbuco and Puyehue-Cordón Caulle. This evidence supports the notion that ice melt can influence volcanic activity.
"The buoyancy effect from melting ice allows magma chambers deep within the continent to expand, altering pressure and accelerating processes that lead to eruptions," notes the study.
This situation creates feedbacks known as ice albedo feedbacks, where reduced ice cover decreases the Earth's albedo effect, leading to further warming of the atmosphere and worsening the melting process. This interplay between melting ice and volcanic activity presents a complex challenge that could exacerbate the effects of climate change.
The article was written with the assistance of a news analysis system.