Icelandic Shift: The ground near the Grímsvötn volcano in Iceland shifted half a metre just
before a major eruption in 2011.
Source: Nature News
An Icelandic volcano that spurted out a 20-kilometre-high ash plume in May 2011 has given researchers another possible tool for forecasting future eruptions.
An hour before the Grímsvötn volcano erupted, a Global Positioning System (GPS) instrument perched on its flanks showed the ground shifting noticeably. Those data, streamed in real time back to volcanologists, revealed not only that the eruption was imminent, but also its likely size.
“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,” says Sigrún Hreinsdóttir, a geophysicist at the University of Iceland in Reykjavik. She and her colleagues report the discovery today in Nature Geoscience1.
Knowing that an eruption is about to occur helps emergency officials to prepare for a disaster by closing roads or evacuating nearby residents. And knowing how high a volcano’s ash plume may reach helps airlines to plan for whether they need to re-route flights, or even close airports. The 2011 Grímsvötn event, the largest volcanic eruption in Iceland in nearly a century, temporarily grounded flights in parts of the United Kingdom — a small reminder of the multimillion-euro losses that were incurred as a result of planes being grounded a year before that, when the Icelandic volcano Eyjafjallajökull erupted.This is good news; and as the article points out, early warnings help prevent loss of human and animal lives by putting emergency-action plans into place. But this means that nations that have active volcanoes need to install special monitoring equipment. "But the biggest challenge may be monitoring more volcanoes in real time, says Paul Segall, a geophysicist at Stanford University in California. Many volcano observatories, including that in Alaska, have lost funding in recent years."
You can read the rest of the article at [Nature]