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04 Dec 2022 | 05:52 AM UTC

Indonesia: Volcanic eruptions at Mount Semeru in East Java Province the morning of Dec. 4

Volcanic eruptions at Mount Semeru in East Java Province, Indonesia, the morning of Dec. 4. Exclusion zone in place.

Warning

Event

Officials are maintaining a Level 3 alert (second-highest level on a four-tier scale) for Mount Semeru as of Dec. 4 following multiple eruptions earlier the same day. Authorities recorded an ash plume that reached up to 1.5 km (1 mile) above the surface of Semeru's crater following the first eruption at around 04:11. A second eruption occurred at around 09:18, ejecting ash and gas up to 5 km (3 miles) above the summit. The volcano is approximately 80 km (50 miles) south-southeast of Sidoarjo in East Java Province.

An exclusion zone of a 5 km (3 miles) radius from the crater is in place. Authorities have advised residents to stop all activities in the southeastern sector of the volcano along the Besuk Kobokan River from the crater to 13 km (8 miles) away as well as within 500 meters (1,640 feet) of the Besuk Kobokan River from 13-17 km (8-11 miles) away from the crater. Officials have also advised residents to be vigilant for potential pyroclastic flows, lava flows, and landslides along rivers and valleys on the flanks of Mount Semeru, especially along the Besuk Kobokan and its tributaries, Besuk Bang, Besuk Kembar, and Besuk Sat.

Transportation disruptions are possible over the coming days. Authorities may impose ground travel restrictions along roads in affected areas, as ashfall could reduce visibility and make streets slippery. Further significant eruptions could lead to airport closures or flight delays and cancellations at Malang's Abdul Rachman Saleh Airport (MLG); MLG is around 30 km (19 miles) northwest of the volcano. Indonesia's Volcano Observatory Notice for Aviation (VONA) maintains an orange warning, the second-highest of four levels, indicating that further eruptions could impact flight activity.

Health
Volcanic activity may impact air quality in areas of East Java Province surrounding Mount Semeru, especially Lumajang and Malang regencies. Following an explosive event, air quality could become a concern, particularly in areas near the crater. Individuals in the region - especially those with underlying pulmonary conditions such as asthma or chronic obstructive pulmonary disease (COPD) - may experience difficulty breathing and suffer from lower tolerance to physical exertion.

Advice

In the event of further eruptions, contact airlines for updated flight information; confirm flights before checking out of hotels or driving to the airport. Avoid areas with heavy ash accumulations. If operating in areas affected by the ash cloud, consider remaining indoors in air-conditioned facilities when possible. Those who must be outdoors should use facemasks and observe other precautions to avoid ash inhalation. Drive defensively; seek updated information on road conditions before driving or routing shipments through areas close to the volcano. Heed all official orders.

Resources

Volcano Observatory Notice for Aviation