(Inside Science TV) -- There are 15,000 active volcanoes around the world. Of those, about 50 erupt each year, spewing steam, ash, toxic gases and lava. But scientists don’t know which volcanoes are most likely to erupt. A new tool is helping them to figure that out.
More than 43,000 people live in the shadow of Mauna Loa in Hawaii, the largest volcano on Earth. Another 80,000 people live in the danger zone of Mount Rainier in Washington state.
Volcanoes can explode at any time – endangering the lives of tens of thousands or even millions of people.
Geophysicist Estelle Chaussard of the University of Miami said that the problem is figuring out which ones are likely to erupt.
“Right now, people doing research, they just pick a volcano and put their equipment there, and if they don’t see anything, well, too bad. If they see, something […] that’s good,” Chaussard said.
Now, researchers are using satellite images to forecast volcanic eruptions more accurately.
“What we are hoping to do is actually make forecasts more reliable by actually knowing which volcano we have to survey in the first place,” Chaussard said.
By piecing together the images, scientists can measure a volcano to see if it is inflating due to rising magma inside. Volcanoes that inflate are more likely to erupt.
“We can actually measure how much the volcanoes are growing and we can detect this input of magma in the reservoir; that’s usually a precursor for an eruption,” Chaussard explained.
In a recent study, researchers examined satellite images and found that out of 79 volcanoes in Indonesia, six of them were inflated.
“And three of these volcanoes actually erupted after the signal of inflation” was detected by our team, Chaussard said.
Using the satellite images, scientists can detect changes as small as a couple of millimeters. They are hoping that the combination of images and measurements will help alert people of danger sooner.
It’s a first step toward forecasting when eruptions will happen. Researchers hope satellites will one day be used to monitor every volcano. A new European satellite is expected to launch soon.