Mount Semeru Erupts Again This Morning, Ash Plume 500 Meters Above Peak

Mount Semeru in East Java erupted again on Tuesday (16/12/2025) at 04:44 AM WIB. In the last week, Mount Semeru has erupted 10 times.

According to eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the ash column was observed to be approximately 500 meters above the peak or 4,176 meters above sea level.

The ash column was observed to be white to grey with thick intensity towards the north. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 110 seconds.

(Read: Indications of Forest and Land Fire Area in Central Kalimantan Province in the Last Decade)

According to the MAGMA Indonesia volcano activity report, Mount Semeru's activity level is at Level III (Alert). Seismicity observations on December 16, 2025, from 18:00-23:59 WIB showed 35 eruption earthquakes with amplitudes of 12-22 millimeters and earthquake durations of 82-119 seconds.

Additionally, there was 1 emission earthquake with an amplitude of 6 millimeters and a duration of 28 seconds, and 1 harmonic earthquake with an amplitude of 8 millimeters and a duration of 91 seconds.

PVMBG urges against any activities in the southeast sector along Besuk Kobokan, as far as 13 kilometers from the peak (eruption center). Beyond that distance, people should not conduct activities within 500 meters from the riverbanks (river borders) along Besuk Kobokan, as there is a potential for expansion of hot clouds and lava flows up to 17 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 7,362 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 3,034 occurrences.

(Read: West Kalimantan Produced the Most CO2 Emissions from Forest and Land Fires Until July 2023)