Volcanoes in Java continue to show worrying signs, with authorities closely monitoring seismic activity as they spew lava and ash many kilometres into the atmosphere.

At 3,676 metres (12,060 feet), Mount Semeru in East Java is one of the highest volcanoes in Indonesia. Mount Merapi in central Java is a 2,929-metre (9,610-foot) active volcano with a hiking trail to its summit and a surrounding national park. Both continue to trouble authorities.

On 16 January 2021, the Semeru volcano observatory issued a notice for aviation warning of an ash cloud moving to the north-east with an ash cloud top at around 5,676 metres (18,163 feet) above sea level, but it may be higher than what can be observed clearly.

Here’s a look at this month’s eruptions