Indonesia: Volcanic activity likely to continue at Mount Merapi in Central Java Province through at least late August

Event

Volcanic activity will likely continue at Mount Merapi in Central Java Province through at least late August. Authorities recorded several significant ashfall incidents as well as lava flows and multiple minor earthquakes Aug. 8-10. On Aug. 10, officials reported ashfall in areas roughly 21 km (13 miles) northwest of the volcano's peak.

Indonesia's Center for Volcanology and Geological Hazard Mitigation (CVGHM) has designated Mount Merapi at alert level 3, the second-highest level on a four-tier scale. Officials continue to recommend against any activity within 5 km (3 miles) of Merapi's crater, warning that lava flows could affect areas within that radius. Authorities have also warned residents to avoid rivers originating from the volcano and to be aware of landslides caused by heavy rain in the vicinity of Mount Merapi. Officials may issue evacuation orders if there is increased volcanic activity in the coming days or weeks. The volcano is around 29 km (18 miles) north-northeast of Yogyakarta.

Flight disruptions may occur at nearby airports, including Yogyakarta's Adisutjipto International Airport (JOG), if large eruptions occur and produce significant 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
Volcanic activity may impact air quality in the areas of Central Java surrounding Mount Merapi. Air quality could become a concern, particularly in areas near the crater, following any explosive event. Individuals in the region - especially those with underlying pulmonary conditions such as asthma, chronic obstructive pulmonary disease (COPD), or lung cancer - may experience difficulty breathing and could suffer from lower tolerance to physical exertion.

Advice

In the event of 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 an 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. Follow official instructions.

Resources

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