A new eruption took place at Anak Krakatau volcano, Indonesia at 09:38 UTC (16:38 LT) on January 3, 2022.
The height of the eruption column was observed to be ± 100 m (328 feet) above the summit or about ± 257 m (843 feet) above sea level.
The ash column was observed to be gray to brown with a thick intensity to the northeast.
The eruption was recorded on a seismograph with a maximum amplitude of 47 mm and a duration of 22 seconds.
The Activity Level remains at III (standby).
The public/visitors/tourists/climbers are advised not to approach the volcano or do any activity within a 5 km (3.1 miles) radius of the active crater.
The last eruption at this volcano took place on December 15, 2022, ejecting thick volcanic ash around 857 m (2 742 feet) above sea level or 700 m (2 240 feet) above the summit.
Geological summary
The renowned volcano Krakatau (frequently misstated as Krakatoa) lies in the Sunda Strait between Java and Sumatra. The collapse of the ancestral Krakatau edifice, perhaps in 416 CE, formed a 7 km (4.3 miles) wide caldera.
Remnants of this ancestral volcano are preserved in Verlaten and Lang Islands; subsequently Rakata, Danan and Perbuwatan volcanoes were formed, coalescing to create the pre-1883 Krakatau Island. Caldera collapse during the catastrophic 1883 eruption destroyed Danan and Perbuwatan volcanoes and left only a remnant of Rakata volcano.
This eruption, the 2nd largest in Indonesia during historical time, caused more than 36 000 fatalities, most as a result of devastating tsunamis that swept the adjacent coastlines of Sumatra and Java. Pyroclastic surges traveled 40 km (25 miles) across the Sunda Strait and reached the Sumatra coast.
After a quiescence of less than a half-century, the post-collapse cone of Anak Krakatau (Child of Krakatau) was constructed within the 1883 caldera at a point between the former cones of Danan and Perbuwatan. Anak Krakatau has been the site of frequent eruptions since 1927.2
1 Anak Krakatau volcano updates – PVMBG – January 3, 2023
2 Anak Krakatau – Geological summary – GVP