INFRAME ASIA, NEWS – Indonesia raised the alert status of Anak Krakatau to Level III after the volcano recorded at least 13 eruptions in one day. The country’s Geological Agency said the change took effect at 9 in the evening local time on October 9 after a review of activity recorded since early October. The update was reported by Malay Mail on October 10.
The report said the volcano’s status had been lowered to Level II on September 21 before its activity increased again. Monitoring on October 9 documented a series of eruptions, including an ash column that rose about 250 metres above the summit during one event. Eleven further eruptions were recorded over the evening, although their ash columns could not be observed.
Anak Krakatau lies in the Sunda Strait between the Indonesian islands of Java and Sumatra. It is part of the volcanic system associated with the historic Krakatau caldera, which has undergone major changes through repeated eruptions. Authorities monitor the volcano because explosive activity can produce ash, falling rocks and other hazards around the crater.
Indonesia uses a four-level volcanic alert system, with Level III indicating an elevated state of activity that requires precautionary measures. Officials warned residents and visitors to stay outside a five-kilometre radius from the eruption centre. Access to areas near newly formed volcanic land features was also restricted under the safety advisory.
The Geological Agency said seismic monitoring had not shown a significant overall increase in volcanic earthquakes during the assessment period. However, authorities also reported sulphur dioxide emissions and observed incandescence at the volcano earlier in October. Those observations formed part of the broader assessment used to determine the alert level.
Volcanic ash can pose a danger to people near an eruption and can also affect aircraft when it enters flight paths. The Darwin Volcanic Ash Advisory Centre reported that ash had reached roughly 1.8 kilometres above sea level and drifted westward over the Sunda Strait. The advisory indicated that the ash plume was expected to disperse over several hours.
Officials cautioned against spreading unverified claims about a possible tsunami. They advised communities along the coasts of Banten and Lampung to remain calm and follow information from authorised agencies. Eruptions do not automatically cause a tsunami, and risk assessments depend on the type and scale of volcanic activity.
The latest activity followed stronger eruptions in September, when volcanic ash disrupted air operations and affected thousands of flights. Those earlier disruptions showed that volcanic activity in the strait can have effects beyond the immediate exclusion zone. The October alert, however, is based on the current assessment and should be distinguished from events reported in September.
Residents in coastal areas were asked to follow official guidance and avoid approaching the volcano. Visitors were also warned about volcanic rocks, heavy ashfall, lava flows and sudden secondary eruptions. Authorities advised people to use official updates instead of circulating unverified images or claims on social media.
PVMBG’s monitoring reports documented multiple eruption earthquakes during the day. On October 9, the agency recorded 26 eruption-related seismic events in its full-day observations, according to the report. Seismic records are considered alongside visible activity, gas emissions and other monitoring information when authorities assess changing volcanic behaviour.
The alert status can be reviewed again if monitoring data indicate a change in activity. Volcanologists track factors including eruption frequency, earthquake patterns, gas emissions and observations from the crater area. Any decision to reduce or increase restrictions is made through the responsible agencies’ assessment rather than the number of eruptions alone.
Authorities continued to urge the public to comply with the restricted zones while activity remained elevated. Coastal communities were advised to keep track of official notices and follow instructions from local disaster-management agencies. Further monitoring reports will help establish whether the current level of activity persists or changes.
