It has always been extremely difficult to measure volcanic gas emissions. Now, specially adjusted unmanned aerial vehicles can help researchers collect data from active volcanoes in PNG. These unmanned aerial vehicles can help local communities monitor nearby volcanoes and predict the possible eruption. The measurement results of unmanned aerial vehicles can also provide information about the most inaccessible and active volcanoes on the Earth, and the contribution of volcanoes to the global carbon cycle.
The project takes Manam volcano as the test object. Manam volcano is located on an island only 10 kilometers (6 miles) wide, on the northeast coast of PNG. There are more than 9000 people on the island, and Manam volcano is one of the most active volcanoes in the country. In 2004, a big eruption of Manam destroyed people’s crops and houses and forced the whole island to evacuate to the mainland.
The steep slope of Manam volcano makes it extremely dangerous to collect gas samples artificially, but unmanned aerial vehicles can fly safely into the rolling smoke, thus helping the research team measure its volcanic gas emissions more accurately.
One of the unmanned aerial vehicles was ready for flight tests. The unmanned aerial vehicle flew into the highly turbulent volcanic feather of Manam volcano from a height of 2000 meters (6,561 feet), about 6 kilometers (3.7 miles) from the launching platform.. Every time they fly, these unmanned aerial vehicles will take images of Manam volcano and its two craters, measure the gas composition above the rising plough, and collect four bags filled with gas for rapid analysis when the plane lands. Aerial images of unmanned aerial vehicles show that Manam volcano emissions increased from October 2018 to May 2019. In fact, only one month after the second field visit of researchers (May, 2019), the volcano soon burst out in June.
The increase of volcanic emissions is not the only reliable indicator to determine whether the volcano is about to erupt, so researchers also studied the ratio between different gases (I .e. carbon dioxide CO2 and sulfur dioxide) in Manam volcanic emissions. Combining UAV measurement results with satellite data, researchers can prove that Manam volcano is expected to emit 3700 tons of carbon dioxide CO2 and about 5100 tons of sulfur dioxide SO2 every day, which is higher than the previous predicted value.
Bird’s eye view of Manam volcano “Our new research direction, remote and aerial (UAV) operation, makes field measurement possible. This is currently the only feasible method that can be used to measure the gas chemical characteristics of steep, dangerous and highly active volcanoes (such as Manam).” The research team came to a conclusion.