Volcano Semeru Outburst in Indonesia Triggers Emergency Relocations

Indonesia's Semeru volcano, the tallest summit on the island of Java, has erupted, blanketing several villages with falling ash, prompting evacuations and leading authorities to raise the alert to the highest level.

The volcano in East Java province unleashed blistering plumes of fiery ash and a mixture of rock, lava and gas that moved up to 4 miles down its slopes multiple times from noon to evening, while a dense plume of hot clouds rose 2km into the air, as stated by the nation's geological authority.

The outbursts that occurred throughout the day forced authorities to raise the volcano’s alert level on two occasions, from the third-highest level to the highest, the authority reported. No deaths or injuries have been reported.

More than 300 residents in the three villages most at risk in the district of Lumajang were relocated to official safe havens, according to a representative for the national disaster mitigation agency.

He said that heightened volcanic movements of the volcano on Wednesday afternoon led officials to expand the danger zone to 5 miles from the crater. People were advised to keep away from an zone along the Besuk Kobokan River, which is the path of the lava flow, as scorching gases moved down Semeru’s slopes.

Videos on online platforms showed a dense cloud of volcanic dust moving through a wooded ravine to a river beneath a overpass. Locals, some with faces smeared with volcanic dust and rain, fled to makeshift refuges or departed for alternative secure locations.

Local media reported that emergency teams were facing challenges to rescue about 178 people trapped on the 3,676-metre mountain at the Ranu Kumbolo observation station. The party included 137 hikers, 15 carriers, seven escorts and six tourism officials, according to an official with the national park.

“They are currently safe at the Ranu Kumbolo station,” an official stated in a recorded message. He said the station was located 4.5km from the crater on the northern slope of the volcano, which is outside the trajectory of the fiery cloud movement that was seen moving to the southeast direction. Bad weather and rain forced the group to spend the night there, he explained.

The volcano, also called Mahameru, has burst numerous times in the last two centuries. However, as is the case with numerous of the 129 active volcanoes in the archipelago, tens of thousands of residents continue to live on its fertile slopes.

Semeru’s previous significant explosion was in late 2021, when 51 people were killed and hundreds others were injured and settlements were submerged in thick mud. The event forced the evacuation of over ten thousand residents from their houses.

Indonesia, an archipelago of more than 280 million people, is located along the Pacific “ring of fire”, a horseshoe-shaped series of tectonic boundaries, and is susceptible to seismic events and volcanic activity.