Anak Krakatau ash closes Jakarta airport and strands more than 150,000

Anak Krakatau, the volcanic island in the Sunda Strait between Java and Sumatra, erupted again from late Friday and put ash into the airspace around Jakarta by early Sunday. Soekarno-Hatta International Airport, more than 150 kilometres from the crater, suspended operations from about 1:30 a.m. local time. The halt was extended through the morning and afternoon as the plume drifted.

Indonesia’s meteorological agency BMKG said ash reached 20,000 feet, about 6,000 metres, on the Java side of the volcano and as high as 50,000 feet, about 15,000 metres, on the Sumatra side and over parts of Banten. The Darwin Volcanic Ash Advisory Centre reported continuous ash at flight level 500, moving west at about 30 knots, with lower ash at flight level 200 moving south and southeast.

The geology agency recorded a 30-second eruption at 3:53 a.m. Sunday and a 16-second burst about three hours later. Officials said the volcano produced a lava fountain and booming sounds that could be heard up to 700 kilometres away. Two further eruptions were logged later on Sunday.

How many flights and passengers were stopped

The first official tallies moved as the closure widened. Airport operator Angkasa Pura said 301 flights were affected, including 58 international services. The transport ministry earlier put the figure at 209 flights and 22,798 passengers in one window. Transport Minister Dudy Purwagandhi later said 467 flights had been hit and that six airports were closed after tests showed ash moving toward West Java. By Sunday evening the Associated Press, citing officials, said eight airports were ordered shut until midnight, 1,558 flights were cancelled, including 963 at Soekarno-Hatta alone, and about 170,000 passengers were affected. BBC reporting put the stranded figure above 150,000 across six airports.

AirNav Indonesia closed airspace around Soekarno-Hatta and Halim Perdanakusuma in Jakarta, and around other fields including Radin Inten II in Lampung and Husein Sastranegara in Bandung. Semarang and Surabaya were named as alternate landing sites. Singapore Airlines cancelled its Jakarta services for the rest of Sunday. Qantas reported cancellations on the same route. International links named in the disruption list included Kuala Lumpur, Singapore, Hong Kong, Sydney, Seoul, Doha and Amsterdam.

Purwagandhi told airlines to speed refunds and to keep passengers informed so terminals did not clog. The airport operator said it was issuing food and running buses to hotels with the carriers.

Ash on the ground, not only in the sky

Kompas and other local outlets reported schools cancelling activities on Saturday after students and residents complained of eye irritation. Fishermen stayed in. The disaster mitigation agency said on Saturday there was no imminent tsunami risk from this eruption. That line matters because the 2018 flank collapse at Anak Krakatau did generate a tsunami that killed hundreds on the Java and Sumatra coasts.

The island is the successor cone to Krakatau, whose 1883 eruption destroyed the parent island and killed tens of thousands. Anak Krakatau rose from the sea in the 1920s and has been in frequent, usually modest, eruption for years. The aviation problem on Sunday was height and drift, not a collapse. Jet engines ingesting volcanic glass can fail. That is why an airport 150 kilometres away can shut when a plume is mapped at 50,000 feet.

Passengers at Soekarno-Hatta described looking at blank departure boards and waiting for airline instructions. One domestic traveller, Suhardi, 58, told Reuters he had already lost a connecting flight toward Samarinda and had come to the terminal hoping for a morning substitute.

The next operational question is simple and measurable: when BMKG and the Darwin VAAC drop the high-level ash advisory over western Java, Soekarno-Hatta can reopen. Until then the stranded passenger count is the figure that will keep moving, and it is already in six figures.