Volcanic eruption predictions improved using 3D-printed camera

Gas emissions represent the amount of activity occurring beneath the surface of a volcano. Measuring these emissions lets researchers observe what can’t be seen from the surface.

This knowledge is vital for hazard monitoring and the prediction of future eruptions. Since the mid-2000s, ultraviolet SO2 cameras have become important tools to measure emissions.

However, these cameras typically cost upwards of $20,000 - meaning very few are installed permanently - and need to be continuously manned to harvest the data effectively.

To get better long-term monitoring data, an international team of researchers has developed an SO2 camera to continually measure emission rates from volcanoes.

“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,” said Dr Thomas Wilkes, a researcher at the University of Sheffield and lead author of the study.

Compared to previous models, the researchers’ SO2 camera is significantly cheaper and uses less power, coming in at around $5,000 each.

“Wherever possible we 3D print parts, too, to keep costs as low as we can,” Wilkes explained. “We also introduce a user-friendly, freely available software for controlling the instrument and processing the acquired data in a robust manner.”

The affordability and user-friendliness makes the camera accessible to more volcanologists who otherwise might not have access to datasets containing accurate gas emission rates.

Additionally, the power consumption of the system is low, with an average of 3.75 watts. This is about half of what was needed to power systems presented previously. On sites where there is little solar power to be harnessed this will be especially beneficial, the researchers wrote. Their camera runs on fewer or smaller solar panels or batteries, reducing the overall cost further.

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

The team has already used their camera in two preliminary data sets from Lascar, a stratovolcano in Chile, and Kilauea, a shield volcano on Hawaii’s Big Island, where their camera is in continuous operation.

“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.”

Despite being cost-efficient and easy to use, the researchers pointed to some limitations of SO2 cameras: “They are dependent on meteorological conditions and work best under clear blue skies when the volcanic gas plume moves in a 90-degree angle to the viewing direction of the camera,” said Wilkes.

In December last year, a small drone equipped with an ultra-lightweight sensor system was developed to monitor volcanos from above.