Volcano Mahameru Outburst in Indonesia Prompts Evacuations

The nation's Mount Semeru, the highest peak on the island of Java, has exploded, covering several villages with volcanic ash, prompting evacuations and leading authorities to raise the warning to the highest level.

The volcano in East Java province released blistering plumes of fiery ash and a combination of stone, molten rock, and gases that travelled up to 4 miles down its sides multiple times from midday to evening, while a thick column of hot clouds rose 2km into the sky, as stated by Indonesia’s Geology Agency.

The outbursts that unfolded throughout the day compelled officials to increase the volcano’s alert level twice, from the level three to the highest, the agency said. No deaths or injuries have been announced.

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

He stated that heightened volcanic movements of the volcano on the afternoon of Wednesday prompted officials to expand the danger zone to 5 miles from the crater. Residents were urged to keep away from an area along the Kobokan River, which is the path of the molten rock stream, as scorching gases moved down the volcano's sides.

Videos on online platforms displayed a thick plume of ash sweeping through a wooded ravine to a waterway beneath a bridge. Residents, some with faces smeared with ash and water, escaped to temporary shelters or departed for alternative secure locations.

Local media indicated that emergency teams were struggling to save about 178 people stranded on the 3,676-metre peak at the Ranu Kumbolo monitoring post. The group included 137 climbers, 15 carriers, seven guides and six tourism officials, according to an official with the national park.

“They remain secure at the Ranu Kumbolo station,” a spokesperson stated in a video statement. He noted the station was situated 2.8 miles from the crater on the northern slope of the mountain, which is not in the path of the fiery cloud movement that was seen traveling to the southeast direction. Bad weather and rain forced the group to spend the night there, he explained.

The volcano, also known as Great Mountain, has burst numerous times in the last two centuries. However, as is the situation with many of the 129 active volcanoes in the archipelago, tens of thousands of residents continue to reside on its fertile slopes.

Semeru’s previous significant explosion was in December 2021, when 51 individuals were killed and hundreds others were burned and settlements were buried in layers of mud. The event forced the evacuation of over ten thousand people from their homes.

Indonesia, an archipelago of more than 280 million people, sits along the Pacific seismic belt, a curved series of tectonic boundaries, and is susceptible to seismic events and volcanic activity.