Mount Semeru Outburst in Indonesia Triggers Evacuations

Indonesia's Mount Semeru, the highest peak on Java island, has erupted, blanketing several villages with volcanic ash, prompting evacuations and leading authorities to raise the warning to the maximum level.

The volcano in East Java province unleashed searing clouds of fiery ash and a mixture of stone, molten rock, and gases that travelled up to 7km down its sides multiple times from midday to evening, while a dense plume of fiery clouds rose 1.2 miles into the air, according to Indonesia’s Geology Agency.

The eruptions that occurred throughout the day compelled authorities to raise the volcano’s alert level on two occasions, from the third-highest level to the highest, the authority reported. No casualties have been reported.

More than 300 residents in the three villages most endangered in the district of Lumajang region were relocated to government shelters, as mentioned by a spokesperson for the national disaster mitigation agency.

He said that heightened volcanic movements of the volcano on Wednesday afternoon prompted officials to widen the hazard area to 8km from the summit. People were advised to keep away from an zone along the Kobokan River, which is the path of the molten rock stream, as searing gas flowed down Semeru’s slopes.

Footage on online platforms displayed a dense cloud of volcanic dust moving through a wooded ravine to a river beneath a bridge. Locals, some with faces covered with ash and water, escaped to temporary shelters or departed for other safe areas.

Local media reported that authorities were facing challenges to save about 178 individuals trapped on the 3,676-metre mountain at the Ranu Kumbolo observation station. The group comprised 137 climbers, 15 carriers, seven escorts and six tourism officials, according to an spokesperson with the protected area.

“They are currently safe at Ranu Kumbolo monitoring post,” an official stated in a video statement. He noted the post was located 2.8 miles from the crater on the north side of the mountain, which is outside the trajectory of the fiery cloud movement that was observed traveling to the southeast direction. Inclement conditions and rain required the team to remain overnight there, he explained.

The volcano, also known as Mahameru, has erupted many occasions in the last two centuries. However, as is the situation with many of the 129 live volcanoes in the archipelago, tens of thousands of people still to reside on its fertile slopes.

Semeru’s previous significant explosion was in December 2021, when 51 people were lost their lives and hundreds more were burned and settlements were buried in thick mud. The event led to the evacuation of more than 10,000 people from their homes.

The country, an island chain of over 280 million people, is located along the Pacific seismic belt, a curved series of tectonic boundaries, and is prone to seismic events and volcanic activity.