Over 300 flights cancelled following series of eruptions on Anak Krakatoa.

Over 300 flights have now been cancelled since Anak Krakatoa, a volcanic island located in the Sunda Strait between Sumatra and Java, began erupting on Friday 4 September 2026. The volcano has produced a series of volcanic columns, some of which have reached over 15 000 m above sealevel. This has led to ash falls across the region, with all flights from Soekarno-Hatta International Airport in Jakarta, which is a little over 100 km to the east of the volcano, being cancelled. The Indonesian Ministry of Health is recommending people avoid going outside without dust masks due to the health hazard presented by the ash, which can cause severe breathing problems, and fishing fleets in the area are reportedly avoiding going to sea because of the poor conditions.

Drone footage of an ash column emerging from Anak Krakatoa on Saturday 5 September 2026. Reuters.

Volcanic ash is extremely hazardous to aircraft in a number of ways. At its most obvious it is opaque, both visually and to radar. Then it is abrasive, ash particles physically scour aircraft, damaging components and frosting windows. However the ash is most dangerous when it is sucked into jet engines, here the high temperatures can melt the tiny silica particles, forming volcanic glass which then clogs engine. When this happens the only hope the aircraft has is to dive sharply, in the hope that cold air passing through the engine during the descent will cause the glass to shatter, allowing the engine to be restarted. Obviously this is a procedure that pilots try to avoid having to perform.

Anak Krakatau is a volcanic island located in the Sunda Strait between Sumatra and Java. The volcano (then known simply as Krakatoa) famously exploded in 1883, killing over 36 000 people (possibly over 120 000), largely through a series of tsunamis. This explosion more-or-less completely destroyed the island, but since then a new volcano, Anak Krakatau (meaning the 'son of Krakatoa'), has grown in its place. Anak Krakatau is almost never completely quiet, but goes through periods of greater and lesser activity. An eruption on 22 December 2018 triggered a tsunami which tsunami caused over 430 fatalities, injured 14 000 people, and displaced 33 000 more along the Sunda Strait. The tsunami risk of this area is particularly high as the coast is very popular with both locals and tourists and is home to over 20 million people within a 100 km distance from the volcano.

Anak Krakatau is located to the north of the Sunda Trench, along which the Australian Plate is being subducted beneath the Sunda Plate, on which the island sits. As the Australian Plate is subducted it is partially melted by the friction and the heat of the planet's interior. Some of this melted material then rises through the overlying Sunda Plate, fuelling Krakatau and the volcanoes of Sumatra and Java.

The Subduction zone beneath Sumatra. NASA/Earth Observatory.

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Thirty five confirmed deaths following Magnitude 7.8 Earthquake off the southern coast of Mindanao Island, Philippines.

The Philippine Institute of Volcanology and Seismology recorded a Magnitude 7.8 Earthquake at a depth of 33 km off the south coast of Mindanao Island, Philippines, slightly after 7.35 am on Monday 8 June 2026 local time (slightly after 11.35 pm on Sunday 7 June GMT). 

The location of the 8 June 2026 Mindanao Earthquake. USGS.

Thirty five people have been confirmed dead following this event, with another 134 injured, and a large number of buildings damaged or destroyed, with about 10 000 families displaced as a result of this Earthquake. People reported feeling tremors as far away as Manilla and northern Borneo. Countries around the Pacific Rim issued tsunami warnings after the event, although the largest wave recorded was about 1.4 m. Mindanao has subsequently been hit by a number of large aftershocks. 

A collapsed building in the city of General Santos on Mindanao Island, the Philippines. Department of Social Welfare and Development/Wikimedia Commons.

The geology of the central Philippines is Complex. The west of Mindanao Island is located on the Banda (or Sunda) Microplate, and the east on the Philippine Plate, which is being subducted beneath the Sunda (or Banda) Microplate along the central part of the island. Immediately to the east of the Island the Pacific Plate is being subducted along the Philippine Trench, and passes beneath eastern Mindanao as it sinks into the Earth. This is not a smooth process, an the plates constantly stick together then break apart again as the pressure builds up, resulting in Earthquakes.

Subduction beneath the Philippines. Yves Descatoire/Singapore Earth Observatory.

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Eruption on Mount Kanloan causes ashfall events across Negros Island.

Mount Kanlaon, a 2465 m stratovolcano (cone shaped volcano made up of layers of ash and lava) on the northern part of Negros Island in the central Philippines, erupted slightly before 3.40 pm local time on Thursday 19 February 2026, according to the Philippines Volcano Observatories. The eruption comprised a series of explosions which lasted about two minutes and produced an ash column about 2 km high, and followed by a longer period of gas emissions. 

An eruption on Mount Kanloan, Negros Island, the Philippines, on Thursday 18 February 2026. Philippines Volcano Observatories.

The geology of the Philippines is complex, with the majority of the islands located on the east of the Sunda Plate. To the east of this lies the Philippine Sea plate, which is being subducted beneath the Sunda Plate (a breakaway part of the Eurasian Plate); further east, in the Mariana Islands, the Pacific Plate is being subducted beneath the Philippine Sea Plate. This is not a smooth process, and the rocks of the tectonic plates frequently stick together before eventually being broken apart by the rising pressure, leading to Earthquakes in the process. Material from the subducting Philippine Plate is heated by the temperature of the Earth's interior, causing lighter minerals to melt and the resultant magma to rise through the overlying Sunda Plate, fuelling the volcanoes of the Philippines.

Subduction beneath the Philippines. Yves Descatoire/Singapore Earth Observatory.

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At least ten dead and more than 100 injured following Magnitude 5.5 Earthquake in central Bangladesh.

The United States Geological Survey recorded a Magnitude 5.5 Earthquake at a depth of about 10 km, roughly 30 km to the northeast of the Bangladeshi capital, Dhaka, slightly after 10.35 local time (slightly after 4.35 am GMT) on Saturday 22 November 2025. At least ten people, including at least one child, have died as a result of the event, with more than 100 injured. Most of those killed or injured appear to have been struck by debris falling from buildings in densely populated urban areas; three people were reportedly killed in a single incident when they were struck by a falling balcony. The event was felt across Bangladesh, as well as neighbouring areas of India.

Debris which fell from buildings into a crowded street in Dhaka, Bangladesh, during an Earthquake on 22 November 2025. Reuters.

Earthquake activity in northern Bangladesh is influenced by the uplift of the Tibetan Plateau, due to the impact of India into Eurasia to the south. The Indian Plate is moving northwards at a rate of 5 cm per year, causing it to impact into Eurasia, which is also moving northward, but only at a rate of 2 cm per year. The collision of the Indian and Eurasian plates has led to the formation of the Himalayan Mountains, the Tibetan Plateau, and the mountains of southwest China, Central Asia and the Hindu Kush.

Block diagram showing how the impact of the Indian Plate into Eurasia is causing uplift on the Tibetan Plateau. Jayne Doucette/Woods Hole Oceanographic Institution.

Eastern Bangladesh is also in an area particularly prone to Earthquakes; much of nearby Myanmar lies on the Burma Plate, a small tectonic plate caught between  the Eurasian Plate to the northeast, the Indian Plate to the west and southwest and the Sunda Plate to the southeast. As these larger plates move together the Burma Plate is being squeezed and fractured, with a major fault line, the Kabaw Fault, having formed across much of the north of the country, along which the Burma Plate is slowly splitting. Most Earthquakes in the region are caused by movement on this fault.

The movement of the Burma and surrounding plates. Sheth et al. (2011).

The central part of Bangladesh is potentially affected by both tectonic systems, but is rather less prone to earthquake events, with only six Earthquakes of Magnitude 5.5 or greater since 1950. This may help to explain the level of deaths and injuries associated with this event, although building safety has been a long standing political issue in Bangladesh, marked by events such as the Tazreen Factory Fire in 2012, in which at least 112 people died in a fire at a nine-story factory building with insufficient fire escapes, and the Rana Plaza collapse in 2013, in which an eight story commercial building collapsed, killing 1134 people. Since 2013, the Bangladesh Accord on Fire and Building Safety, 2018 Transition Key Accord, and most recently the Readymade Sustainability Council, have sort to get international garment manufacturing companies operating in Bangladesh to sign up to fire and building safety protocols, but there remains little general building regulation.

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Eruption on Mount Semeru.

People living close to Mount Semeru, a 3676 m high stratovolcano (cone-shaped volcano made up of layers of ash and lava) close to the city of Lumajang in East Java, have been advised to avoid going near the volcano, following an eruption on Wednesday 19 November 2025. The volcano began erupting at about 4.00 pm local time (about 9.00 am GMT) producing an ash column about 5.6 km high, and triggering a series of pyroclastic flows (avalanches of hot rock, ash and gas) which reached as far as 7.00 km from the volcano.

A column of Ash above Mount Semeru on 19 October 2025. Badan Geologi/AP.

Mount Semeru forms part of the Tengger Volcanic Complex is a string of five overlapping stratovolcanoes (cone-shaped volcanoes) forming a single massif, extending northward from Semeru. The whole massif sits within a vast caldera (volcanic crater), left by the explosion of an ancient volcano about 150 000 years ago. The volcanoes are at the center of this caldera, surrounded by a vast sea of sand, the Tengger Sand Sea.

The approximate location of Mount Semeru. Google Maps.

The Indo-Australian Plate, which underlies the Indian Ocean to the south of Java, is being subducted beneath the Sunda Plate, a breakaway part of the Eurasian Plate which underlies Java and neighbouring Sumatra, along the Sunda Trench, passing under Java, where friction between the two plates can cause Earthquakes. As the Indo-Australian Plate sinks further into the Earth it is partially melted and some of the melted material rises through the overlying Sunda Plate as magma, fuelling the volcanoes of Java and Sumatra.

Subduction along the Sunda Trench. Earth Observatory of Singapore.

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