Jakarta Air Quality Hits Unhealthy Levels After Volcanic Ash Spread
Jakarta's air quality has reached unhealthy levels with an AQI of 151, driven by volcanic ash from Mount Anak Krakatau spreading across the capital.
JAKARTA — Air quality in Indonesia’s capital plummeted on Sunday, Sept. 6, 2026, as hazardous volcanic ash from the erupting Mount Anak Krakatau drifted into the metropolitan area. By 7:00 p.m. local time, the city’s Air Quality Index (AQI) surged to 151, a level classified as unhealthy for the general population.
This sharp decline marks a significant deterioration from earlier in the day, when the AQI recorded 117 at 9:20 a.m., then considered unhealthy only for sensitive groups. Data from the air quality monitoring platform IQAir identifies PM2.5 particulate matter as the primary pollutant, reaching a concentration of 42 micrograms per cubic meter. Public health officials are urging vulnerable residents, including children, the elderly, and pregnant women, to minimize outdoor activities and wear masks to mitigate respiratory risks.
Volcanic Plumes Affecting Java and Beyond
The spread of ash from the Sunda Strait volcano has been confirmed by regional meteorologists. Ana Oktavia Setiowati, Acting Head of the Meteorology, Climatology, and Geophysics Agency (BMKG) Region II, officially verified that volcanic plumes have reached parts of Jakarta. Satellite analysis from the Himawari-9 weather satellite as of 6:00 a.m. confirmed two distinct ash clusters.
Technical reports from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) and the Volcanic Ash Advisory Center (VAAC) in Darwin indicate that the ash has reached altitudes of up to 20,000 feet. The trajectory of the plume is currently tracking toward the northeast and south, blanketed across Banten, West Java, and parts of the capital.
Global Air Quality Rankings
The influx of volcanic material has pushed Jakarta into the top ten cities globally for poor air quality. By Sunday evening, the capital sat in ninth place with an AQI of 106, trailing behind cities including Kuching and Kuala Lumpur in Malaysia, Kolkata in India, Dakar in Senegal, and Tel Aviv-Yafo and Jerusalem in Israel.
The mixture of fine volcanic ash and existing urban pollutants creates a heightened environmental hazard. This combination poses immediate risks for residents with pre-existing conditions, particularly asthma and chronic obstructive pulmonary disease. The situation remains fluid as winds continue to carry volcanic debris from the Sunda Strait toward the densely populated regions of Western Java.
