Indonesia: Mount Merapi in Java erupts March 11; authorities maintaining Level 3 (Standby) alert

Event

Mount Merapi, located in the Special Region of Yogyakarta and Central Java Province, in Java, erupted March 11, sending plumes of hot ash and cloud up to 7 km (4 miles) into the air. A lava flow of 1.5 km (0.9 miles) has also been reported. Authorities have not mandated any evacuations as of writing, but are maintaining a Level 3 (Standby) alert ( the second-highest level on a four-tier scale), which has been in place since November 2020. Authorities have halted mining and tourism activities, and advised individuals to stay away from potential hazard areas and exercise heightened vigilance.

Voluntary or mandatory evacuations are possible in areas near Mount Merapi over the coming days.

Health
Further volcanic activity may impact air quality in parts of Java, particularly in areas nearest the crater. Individuals in the region - especially those with underlying pulmonary conditions such as asthma, chronic obstructive pulmonary disease (COPD), or lung cancers - may experience difficulty breathing and could suffer from lower tolerance to physical exertion.

Transport
Road conditions could quickly deteriorate during periods of significant ashfall, and visibility could be reduced. Officials might close roads near the volcano depending on the presence of hazardous volcanic material. Fine particulate matter ejected from the volcano could pose a hazard to flights in the surrounding airspace. Authorities may temporarily close airport facilities if significant ashfall accumulations occur.

Advice

Confirm flights before checking out of hotels or driving to nearby airports; contact airlines for updated flight information in the event of a major eruption. Avoid areas subject to heavy ash accumulation. If operating in areas affected by ash plumes, consider remaining indoors in air-conditioned facilities when possible. Those who must be outdoors should wear a facemask 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 (VONA)
MAGMA Indonesia - List of Volcanic Activity Levels (Indonesian)