Antarctica’s ice melt poses a significant threat to its hidden volcanoes, which could erupt due to reduced pressure on magma chambers beneath the surface. At least 100 subglacial volcanoes are scattered across the continent, many clustered along its western coast. As the ice sheet melts, it removes weight over the rocks below, causing compressed magma to expand and increase pressure on chamber walls.
This expansion can lead to eruptions, potentially releasing copious amounts of volatile gases that were normally dissolved into the magma. The process is slow, taking hundreds of years, but could create a feedback loop where reduced pressure from surface melting ice leads to further volcanic eruptions.
The study by Coonin et al. suggests that gradual melt could increase the number and size of subglacial eruptions due to this unloading effect. Antarctica’s volcanoes, including iconic Mount Erebus, are already active, with some lava lakes forming on its flanks. The melting ice sheet has been shown to increase volcanic activity in similar regions globally.
While the risk is significant, it’s essential to note that these events will be gradual and may occur even if global warming efforts curb anthropogenic emissions. Antarctica’s history suggests that unloading and expansion of magma could have contributed to past eruptions. The authors stress that the process is slow, but the consequences of these eruptions on the ice sheet could be severe, potentially weakening its structure.
Source: https://www.livescience.com/planet-earth/antarctica/antarctica-ice-melt-could-cause-100-hidden-volcanoes-to-erupt