Powerful, low-cost camera could predict volcanic explosions

Now, to break these barriers, an international team of researchers has developed an SO₂ camera to measure emission rates from volcanoes continually. 

"Our instrument uses a sensor not dissimilar to smartphone camera sensors. It is modified to make it sensitive to ultraviolet light, therefore enabling SO₂ detection," explained lead author Dr. Thomas Wilkes in a press release, a researcher at the University of Sheffield.

Partly 3D-printed and high-power efficiency

The new design has a price tag of about $5,000, making the cost of the parts—some of which are 3D-printed—less than about a fourth of that of earlier models.

"We also introduce a user-friendly, freely available software for controlling the instrument and processing the acquired data in a robust manner," Wilkes said. 

The system is also energy-efficient, with an average power consumption of 3.75 Watts—around half of what was required to power the earlier designs.

According to the researchers, this will be especially helpful at locations where little solar energy can be captured. Their camera uses fewer, smaller, or cheaper solar panels or batteries, lowering the price.

While there are other tools to measure volcanic emissions, "the SO₂ camera can provide higher time- and spatial-resolution data which could facilitate new volcanological research when installed permanently," argued Wilkes.

"Before now, only three volcanoes have had permanent SO₂ cameras installed on them," Wilkes said. 

"Discrete field campaigns have been carried out, and whilst they can be invaluable for a range of research questions, it is important to be able to measure volcanic activity continuously since it can vary substantially from minutes to decades to centuries and beyond."

Wilkes and his team also presented two early data sets from Kilauea, a shield volcano in Hawaii's Big Island, and Lascar, a stratovolcano in Chile, where their camera is constantly operating.

The researchers did, however, note a few SO₂ camera limitations. This includes that they are weather-dependent, performing best in clear, blue skies with the volcanic gas plume moving at a 90-degree angle to the camera's field of view.

The complete study was published in Frontiers in Earth Science on April 3 and can be found here.

Study abstract:

Since its introduction to volcanology in the mid-2000 s, the SO2 camera has become an important instrument for the acquisition of accurate and high time-resolution SO2 emission rates, aiding in hazard assessment and volcanological research. However, with the exception of a few locations (Stromboli, Etna, Kīlauea), hitherto the majority of measurements have been made on discrete field campaigns, which provide only brief snapshots into a volcano’s activity. Here, we present the development of a new, low-cost, low-power SO2 camera for permanent deployment on volcanoes, facilitating long-term, quasi-continuous (daylight hours only) measurements. We then discuss preliminary datasets from Lascar and Kīlauea volcanoes, where instruments are now in continuous operation. Further proliferation of such instrumentation has the potential to greatly improve our understanding of the transient nature of volcanic activity, as well as aiding volcano monitoring/eruption forecasting.