Indonesia: Mount Semeru in East Java Erupts Eight Times in a Single Morning

Mount Semeru is observed to be active at the moment. Local authorities set exclusion zone. The last major eruption in 2021 claimed at least 51 souls.
The peak of Mount Semeru after a major eruption in 2021. (Photo: BNPB)
The peak of Mount Semeru after a major eruption in 2021. (Photo: BNPB)

Mount Semeru, standing 3,676 meters above sea level in Lumajang Regency, East Java, experienced continuous eruptions, up to eight times from Saturday morning to noon on June 1, 2024.

The first eruption occurred at 07:39, followed by subsequent eruptions at 07:49, 08:04, 08:20, 09:52, 11:34, 11:50, and the final one at 13:10 local time.

"Mount Semeru erupted on Saturday, June 1, 2024, at 07:39 Western Indonesia Time, with an ash column height observed at around 400 meters above the summit or 4,076 meters above sea level," said Liswanto, an officer at the Mount Semeru Observation Post, in a written statement received by Antara in Lumajang on Saturday.

Read also: Major Volcanic Eruption in Indonesia: Mt Semeru Spews Hot Ash Clouds and Lava, Casualties Reported

The volcanic ash column was observed to be white to gray with moderate intensity towards the south, and as the report was made, the eruption was still ongoing.

The visual height of the eruptions from the first to the fourth was observed to be between 300 and 500 meters above the summit, while the fifth to the eighth eruptions were not visually observed due to fog cover.

The height of the ash column for the eighth eruption at 13:10 was not observed, but the eruption was recorded on the seismograph with a maximum amplitude of 23 mm and a duration of 97 seconds.

From January 1 to June 1, 2024, at 14:00, a total of 343 eruptions of Mount Semeru had been recorded by the Mount Semeru Observation Post.

Mount Semeru, the highest mountain on the island of Java, remains at Alert Level III. The Center for Volcanology and Geological Hazard Mitigation (PVMBG) recommends that the public avoid any activities in the southeastern sector along Besuk Kobokan within 13 kilometers of the summit (eruption center).

Beyond that distance, the public is also advised to avoid activities within 500 meters from the edge of the river along Besuk Kobokan due to the potential expansion of hot clouds and lava flows extending up to 17 kilometers from the summit.

Additionally, residents are prohibited from engaging in activities within a five-kilometer radius of the crater/summit of Mount Semeru due to the risk of falling incandescent rocks.

The public is also urged to be vigilant of potential hot clouds, lava flows, and lahars along rivers/valleys that originate at the summit of Mount Semeru, especially along Besuk Kobokan, Besuk Bang, Besuk Kembar, and Besuk Sat, as well as potential lahars in small rivers that are tributaries of Besuk Kobokan.

The last major eruption of Mount Semeru eruption occurred on December 4, 2021. The eruption resulted in at least 51 deaths, 169 injuries, and 22 missing persons. Additionally, 45 people suffered burns due to the pyroclastic flow.