Semeru Empat Kali Erupsi Dalam Hari, Warga Diminta Tingkatkan Kewaspadaan

Mount Semeru erupted with an eruption height of up to 1 km above the peak on Sunday (7/12/2025). BETWEEN/HO-PVMBG

JAKARTA - The phenomenon of volcanic activity has returned to public attention after several volcanoes in Indonesia have shown an increase in eruptions in recent weeks.

One of them is Mount Semeru, the highest mountain on the island of Java, which again shows its explosive activities. This periodic eruption serves as a reminder that the Indonesian archipelagic region is in a geological prone zone so that official vigilance and information become important for the surrounding community.

Mount Semeru, which is located on the border of Lumajang and Malang Regencies, East Java, was recorded to have experienced four eruptions on Sunday with an eruption height of up to one kilometer above the peak.

The first eruption occurred at 04.14 WIB with a column of ash as high as approximately 900 meters. The volcanic material in white to gray color looks thick and moves to the south and southwest. Based on the seismograph record, the incident had a maximum amplitude of 22 mm with a duration of 124 seconds.

"The second eruption occurred at 05.10 WIB with an eruptive column height of about 1,000 meters above the peak or 4,676 meters above sea level (masl)," said Mount Semeru Observation Post Officer Sigit Rian Alfian in a written report received in Lumajang. The ash column is white to gray again observed to be thick in the south and southwest, with a maximum seismograph amplitude recording of 22 mm and a duration of 153 seconds.

The next activity was recorded at 07.12 WIB with the ash column reaching the same height, which was around 1,000 meters, and returned to the southwest. This eruption was recorded to last for 156 seconds with a maximum amplitude of 22 mm. Then at 14:19 WIB there was a fourth eruption without clear eruption visuals, but the activity was still recorded by monitoring tools with a maximum amplitude of 21 mm for 102 seconds.

Sigit explained that the status of Mount Semeru is still at Level III or Alert so that people are asked to fully comply with recommendations from the Center for Volcanology and Geological Hazard Mitigation (PVMBG). Residents are prohibited from carrying out any activity in the southeast sector along Besuk Kobokan within a radius of 13 kilometers from the eruption center. Outside the zone, people are still asked to keep a minimum distance of 500 meters from the riverbank because the area is still potentially hit by hot clouds or lava flows up to 17 kilometers.

In addition, residents are asked not to enter the area within a radius of five kilometers from the crater because it is at risk of being hit by incandescent stones. People around rivers and valleys that originate at the peak of Semeru are also asked to remain alert to potential hot clouds of avalanches, lava flows, and lava floods, especially in the Besuk Kobokan, Besuk Bang, Besuk Kembar, and Besuk Sat streams.