Indonesia: Further volcanic activity likely at Mount Sinabung in North Sumatra Province through late April /update 4

Event

Additional volcanic activity is likely at Mount Sinabung in Karo Regency, North Sumatra Province, in the coming weeks following recent eruptions. Significant activity has occurred at the volcano since early January, with additional eruptions occurring in February and March. On March 30, a volcanic event produced ash plumes as high as 1 km (0.6 miles) from the summit. Ashfall is likely in areas surrounding the volcano following eruptions. As of March 30, Indonesia's Volcano Observatory Notice for Aviation (VONA) continues to maintain the warning level of orange, the second-highest of four levels. The volcano is approximately 55 km (35 miles) southwest of Medan.

Authorities continue to enforce a 5-km (3.1-mile) exclusion zone from Mount Sinabung's summit. Officials warn residents living along rivers near the mountain about the possibility of lava, pyroclastic flows, and lahars (debris flows) if a powerful eruption occurs. Any periods of heavy precipitation could exacerbate the threat. Evacuation orders are possible if additional eruptions occur.

Flight disruptions are possible at Kualanamu International Airport (KNO), which serves the city of Medan, if additional significant eruptions occur. Minor delays are also possible on routes serving other destinations in the region if planes detour around ash clouds. Authorities may impose ground travel restrictions along roads in affected areas, as ash could reduce visibility and make streets slippery. Localized ground traffic disruptions are possible.

Health
Any additional volcanic activity may impact air quality in areas surrounding Mount Sinabung, especially Deli Serdang, Karo, and Langkat regencies. Air quality could become a concern, particularly in areas near the crater, following an explosive event. Individuals in the region - especially those with underlying pulmonary conditions such as asthma or chronic obstructive pulmonary disease (COPD) - may experience difficulty breathing and could 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 protective face coverings 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.

Resources

MAGMA Indonesia
Center for Research and Development of Geological Disaster Technology (BPPTKG) Twitter page (Indonesian)
Kualanamu International Airport