Advanced Sensor Technology Provides Accurate Volcanic Gas Measurements

Scientists from the University of Manchester have created a sophisticated sensor that can quickly and accurately identify volcanic gases. Their findings were published in the journal Science Advances.

New research suggests that previous estimates of carbon dioxide (CO₂) volcanoes were significantly underestimated.

The research team analyzed emissions at Soufrière Hills Volcano on the Caribbean Island of Montserrat using a sensor installed on a helicopter. They discovered that the volcano released three times more CO₂ as previous studies had predicted.

Scientists typically focus on hot vents called fumaroles, which emit large amounts of easily detectable acid gases like sulfur dioxide (SO₂) and hydrogen chloride (HCl).

However, many volcanoes also have colder fumaroles, where acidic gases are absorbed by the volcano's water-rich hydrothermal systems, making them more difficult to detect. As a result, CO₂ emissions from these cooler sources are often overlooked, leading to significant underestimation of volcanic gas output.

The new method, which reveals these hidden emissions, provides a more accurate measurement of gas production from volcanoes.

These findings have important implications for volcanic monitoring and eruption prediction.

Volcanoes play a crucial role in the Earth's carbon cycle, releasing CO₂ into the atmosphere, so understanding the emissions is crucial for understanding its impact on our climate. Our findings demonstrate the importance of fast sampling rates and high-precision sensors, capable of detecting large contributions of cooler CO₂-rich gas.

Alexander Riddell, Study Lead Researcher, The University of Manchester

Riddell added, “However, it is also important to realize that despite our findings that CO₂ emissions could be around three times higher than we expected for volcanoes capped by hydrothermal systems, volcanoes still contribute less than 5 % of global CO₂ emissions, far less than human activities such as fossil fuel combustion and deforestation.”

Mike Burton, Professor of Volcanology at The University of Manchester and study co-author, added, “Development of high-sensitivity high-frequency magmatic gas instruments opens up a new frontier in volcanological science and volcano monitoring. This work demonstrates the new discoveries which await us. By capturing a more complete picture of volcanic gas emissions, we can gain deeper insights into magma movement, and observe potential signs of impending eruptions and signs that an ongoing eruption might be ending.”

Burton added, “For the people living near active volcanoes, such advancements could enhance early warning systems and improve safety measures.”

The research was conducted in collaboration with the Montserrat Volcano Observatory and the National Institute of Optics in Firenze, Italy. The study team is currently seeking funding to make this device compatible with unmanned aerial vehicle platforms, which would enable precise gas measurements in challenging and hazardous conditions.

Journal Reference:

Riddell, A., et al. (2025) Quantification of low-temperature gas emissions reveals CO₂ flux underestimates at Soufrière Hills volcano, Montserrat. Science Advances. doi.org/10.1126/sciadv.ads8864.