Scientists are enlisting satellites to alert them to imminent volcano eruptions.
Researchers in Iceland believe that GPS devices, placed near volcanoes, could be used to detect shifts in the ground that often precede an eruption, the journal Nature reported this week.
A GPS device perched on an outcrop near Iceland's Grímsvötn volcano in April 2011 sensed the ground lurching by as much as a meter, then sent data to alert scientists and others nearby. The volcano erupted just an hour later, shooting smoke and ash more than 20 kilometers into the sky and grounding flights as far away as the United Kingdom.
Coming just one year after the Eyjafjallajökull volcano eruption, which halted flights across Western Europe, the Grímsvötn eruption later was determined to be Iceland's largest volcanic event in almost a century.
"A GPS site can tell you not only that there's unrest at a volcano, but that it's about to erupt and then how high its plume will be," Sigrún Hreinsdóttir, geophysicist at the University of Iceland in Reykjavik, told Nature.
Unlike seismic instruments, he explained, GPS instruments collect data that can be used to figure out the amount of pressure that's building underground, therefore predicting the actual size of the eruption – potentially critical information for emergency responders.
For now, though, researchers are waiting to test GPS instruments at one more "volcanic event," Nature reported.
"We need another eruption to prove we are right," Hreinsdóttir said.