Scientists watch and wait as Bali volcano stirs
KARANGASEM: The question Indonesian volcanologist Devy Kamil Syahbana gets most is the one he cannot answer – when, or if, rumbling Mount Agung on Bali island will blow up in a major eruption.
The 3,000m Agung – a strato-volcano capable of very violent eruptions – has recorded a sharp rise in activity that has raised worries about a repeat of a 1963 eruption that killed more than 1,000 people.
“There’s no instrument in the world that can estimate precisely when there will be a major eruption,” said Syahbana, who runs an observatory monitoring the towering volcano, just outside a 10km exclusion zone.
“People expect certainty but volcanology is a science of probability,” he said pointing to charts showing dramatic fluctuations in the seismic activity deep under Agung.
Authorities raised the alert status to the maximum after the volcano started erupting last month, spewing ash over the holiday island and causing travel chaos by closing its airport for three days last week.
While hot magma has produced an eerie orange glow just above the crater, and thousands of villagers have fled from their homes on the mountain’s slopes, Agung has, this time, yet to explode violently.
Syahbana, who studied volcanology in Brussels and Paris, said his team’s main job was to “increase the preparedness of the communities here in the event of a major eruption”.
He said safety was his priority, never mind that raising the alert level had spooked residents and tourists alike.
Syahbana said he had not come under any pressure to lower the alert, though his team was aware of the costs for Indonesia’s main tourist destination, famous for its beach- es and temples.
Indonesia has nearly 130 active volcanoes, more than any other country. Syahbana has surveyed and installed instruments on many of the most active ones, including Mount Merapi on Java island, to the west of Bali, and on Mount Sinabung in the north of Sumatra island.
His team of 16 scientists takes sixhour shifts to monitor seismic stations on Agung that record tremors deep inside the mountain, GPS trackers that record changes in land features and CCTV cameras that provide 24-hour surveillance.
“The difference between other volcanoes and Mount Agung is that there are no scientific records about previous eruptions here, only people’s experiences,” Syahbana said.
In 1963, pyroclastic flows of lava and rocks poured out of the volcano, killing more than 1,000 people and razing dozens of villages.
According to survivors, that eruption was preceded by earthquakes, volcanic mudflows and ashfall – all signs that Mount Agung is showing again now. — Reuters