Sumeru on 6th Dec image by kenziefesti

Mount Semeru erupts in Indonesia, Spews huge ash cloud, cools down after 2 days

Only a year after its most recent eruption, Mount Semeru, the tallest volcano on the island of Java in Indonesia, erupted on Saturday, 4th Dec 2021.

It shot black smoke and ash clouds thousands of feet in the air.

However, the eruption caused no disruption in flights.

Semeru December 2021 Image Credit yudhabaskoro
Semeru December 2021 Image Credit yudhabaskoro


Mount Semeru is 3,600 meters high and is one of the 130 active volcanoes of Indonesia. Its recent eruption was recorded in January 2021.


Indonesia lies on the ‘Pacific Ring of Fire’, a highly seismically (relating to earthquake or other earthly vibrations) active zone.

Map_indonesia_volcanoes Image Credit Wikipedia Lyn Topinka USGS
Map_indonesia_volcanoes Image Credit Wikipedia Lyn Topinka USGS

The high activity of this zone is caused by the movement of the tectonic plates (massive
irregular shaped slabs of solid rock belonging to both continental and oceanic surface) in the region.

The explosion covered many villages in ash and dust. Rescue missions started all over Indonesia and the world, and the Red Cross has started relief operations.

On Monday, the mountain appeared to be calmer. Some sporadic ash was observed.