Researchers test drones to measure volcanic gases in Sicily

Researchers on the Aeolian island of Vulcano, off Sicily, are testing whether drones can help measure volcanic gases and improve efforts to anticipate eruptions.

A team from the Technical University of Munich is testing a system in which a ground sensor sends an invisible laser beam through volcanic gas emissions to a reflector carried by a drone. Marius Schaab, a researcher with the team, said the drone can move around and change angles so the system can take fuller measurements while keeping the sensor and drone out of the corrosive gas plume. An algorithm then uses the returned signals to map gas concentrations during a 10- to 15-minute flight path at distances of up to 60 metres.

Vulcano's Grand Crater last erupted in the late 19th century, but the volcano still has intense degassing activity. The TUM team said this is the first time it has tested its drone system on a volcano. The system can work at altitudes of up to 3,000 metres.

Another German team, from the University of Mainz, is using a 2.5-kilogram drone carrying sensors to fly into fumaroles, where gases and vapour escape at temperatures of 100C to 140C. The drone, named Tina, measures gases, particles and halogens such as chlorine and bromine during flights of up to 40 minutes.

Tjarda Roberts, a researcher at France's National Centre for Scientific Research who is working with the Mainz team, said gas and particle measurements can help scientists understand the atmospheric effects of volcanic emissions. She said they can also help anticipate eruptions because gas composition can change before an eruption. Researchers said drones can reduce the need for people to enter hazardous gas areas and can be used on volcanoes where reaching the summit on foot is difficult or impossible.

The drone is expected to face another test at Mount Etna, the 3,000-metre active volcano in eastern Sicily, where a new eruption has just occurred.