Melting glaciers and ice sheets could trigger a wave of volcanic eruptions, study says
Adamian Vaughan, Environment Editor, The Guardian
A study in Chile has revealed that climate change increases the likelihood and explosiveness of volcanic eruptions, with potential risks also identified in Antarctica.
A study in Chile has revealed that climate change increases the likelihood and explosiveness of volcanic eruptions, with potential risks also identified in Antarctica.
A study reveals that the climate crisis is increasing the likelihood of explosive volcanic eruptions due to melting glaciers and ice sheets.
The loss of ice is reducing pressure in underground magma chambers, increasing the risk of volcanic eruptions. This process has been seen in Iceland; an unusual island located on a mid-ocean tectonic plate boundary. The Chilean study is one of the first to show increased volcanic activity on a continent since the last ice age.
Global warming caused by the burning of fossil fuels is melting ice sheets and glaciers around the world. The greatest risk of renewed volcanic activity is in West Antarctica, where at least 100 volcanoes lie beneath thick ice. As global warming continues, this ice is likely to be lost in the coming decades and centuries.
Volcanic eruptions can temporarily cool the planet by spewing sunlight-reflecting particles into the atmosphere. However, continued eruptions will increase the levels of significant greenhouse gases in the atmosphere, including carbon dioxide and methane. This will further warm the planet, potentially causing a cycle where rising temperatures melt ice, increasing volcanic activity and global warming.
Pablo Moreno-Yaeger from the University of Wisconsin-Madison stated that, as glaciers retreat due to climate change, volcanoes are erupting more frequently and explosively.
The study, shared at the Goldschmidt Geochemistry Conference in Prague and currently under peer review, involved camping in the Andes Mountains, near active and dormant volcanoes.
A study of the Cho-Choshuenco volcano in the Chilean Andes used radioisotope dating to determine the age of volcanic rocks from before, during, and after the last ice age, when a 1,500-meter-thick Patagonian Ice Sheet covered the region. Analysis of the rocks’ mineralogy also revealed the depth and temperature of the rocks.
Data shows that a thick ice sheet lowered eruption volume between 26,000 and 18,000 years ago, allowing a large magma reservoir to form 10–15 kilometers (6.2–9.3 mi) beneath the surface. About 13,000 years ago, a pressure release in the magma chamber led to the expansion of gas in molten rock, causing explosive eruptions.
Researcher Moreno-Yaeger stated that after glacial erosion, the volcano erupted more frequently and underwent structural changes. As the magma melted the tectonic rocks, the structure of the eruptions changed. This made the molten rock more viscous and explosive during eruptions.
Iceland has experienced volcanic eruptions related to the melting of glaciers and ice sheets. Photo: Anadolu/Getty Images
Our study indicates that this phenomenon is not just in Iceland, where volcanic activity has increased, but also in Antarctica. “Other continental regions, such as North America, New Zealand, and parts of Russia, now deserve more scientific attention.”
Previous studies indicated that global volcanic activity has increased two to six times since the last ice age, but the Chilean study is the first to reveal the reasons behind this. A similar phenomenon was reported in 2004 through analysis of rocks in eastern California.
A recent scientific review found that there is limited research on the impact of the climate crisis on volcanic activity. Further research is essential to help mitigate the effects of volcanic eruptions on people and their livelihoods, as well as the potential climate-volcano feedback loops that could worsen the climate crisis. For example, more intense rainfall is also expected to increase violent explosive eruptions.
(Edited by Rahman Mahfuz)
Courtesy: The Guardian
