Researchers keep an eye on volcano emissions

Seventeen of the world’s most active volcanoes have been supplied with monitoring equipment to measure their emission of sulphur dioxide in an effort to make it easier to predict volcano eruptions, and to improve today’s climate models.

Cleveland Volcano in the Aleutian Islands of Alaska photographed from the International Space Station.

The most active volcanoes in the world have special observatories that monitor them in order to be able to sound the alarm and evacuate people in the vicinity if an eruption threatens. These observatories keep track of several parameters, primarily seismic activity. Now 17 observatories can monitor a new parameter – the volcanoes’ emissions of sulphur dioxide.

“Increasing gas emissions may indicate that magma is rising inside the volcano,” said Mattias Johansson of the Department of Radio and Space Science at Chalmers in Sweden. “If this information is added to the other parameters, better risk estimates can be made at the observatories.”

The equipment allows total amount of gas emitted to be measured, whereas most other methods for metering gas can only indicate the gas concentration at a particular point. This is made possible by placing two or more instruments in different places around the volcano and then collation of the information.

The real challenge was make the equipment sufficiently automatic, robust, and energy-efficient for use in the inhospitable environment surrounding volcanoes, in poor countries with weak infrastructure.

“I have primarily been working with the software required for processing and presenting the measurement results,” said Johansson. “Among other things, I have created a program that analyses the data collected, calculates the outward flow of gas, and presents the information as a simple graph on a computer screen that the observatory staff need only glance at to find out how much sulphur dioxide the volcano is emitting at any particular time.”

The team also say it will also be possible to improve global climate models when the researchers receive continuous reports about how much sulphur dioxide is emitted by the 20 most active volcanoes.

“Sulphur dioxide is converted in the atmosphere to sulphate particles, and these particles need to be factored into climate models if those models are to be accurate,” said Associate Professor Bo Galle.

The methods that Johansson has developed can also be used to measure the total emissions of air pollutants from an entire city. China has already purchased equipment that they are now using to study the pollution situation in Beijing.