Anak Krakatau Volcano

Context

Anak Krakatau erupted in Indonesia in September 2026, releasing volcanic ash that disrupted air travel and affected 1,500+ flights at several airports, including Jakarta’s Soekarno-Hatta International Airport. The eruption highlighted the threat volcanic ash poses to aircraft engines and flight safety.

About Anak Krakatau

1. Location: Located in the Sunda Strait, between Java and Sumatra, Indonesia, within the Pacific Ring of Fire.
2. Origin: Meaning “Child of Krakatau”, it developed in the 1883 Krakatau caldera and emerged above sea level in the 1920s.
3. Activity: It has remained active, with repeated Strombolian eruptions involving intermittent explosions and lava ejection.

Why is Anak Krakatau Significant?

1. The 1883 Krakatau eruption caused massive tsunamis and temporary global cooling.
2. In 2018, a flank collapse of Anak Krakatau into the sea triggered a tsunami, causing 400+ deaths in Java and Sumatra.
3. It shows how volcanic activity can trigger secondary hazards such as landslides and tsunamis.

What is a Stratovolcano?

1. A stratovolcano (composite volcano) is a steep, cone-shaped mountain built from alternating layers of lava, volcanic ash and tephra.
2. It usually contains thick, silica-rich (viscous) magma, which traps gases and can cause explosive eruptions, producing ash and pyroclastic flows.
3. They mainly form at subduction zones along convergent plate boundaries, especially around the Pacific Ring of Fire.
4. Examples: Mount Fuji in Japan, Mount St. Helens in US and Mount Vesuvius in Italy.

FAQs

Q1. Where is Anak Krakatau located?
Ans: It is located in the Sunda Strait, between Java and Sumatra in Indonesia.

Q2. What type of volcano is Anak Krakatau?
Ans: It is a stratovolcano (composite volcano) formed through repeated accumulation of lava and volcanic materials.

Q3. Why is Anak Krakatau called the “Child of Krakatau”?
Ans: It developed from the volcanic system associated with the 1883 Krakatau eruption, emerging above the sea in the 1920s.

Q4. What is the Pacific Ring of Fire?
Ans: It is a broad zone around the Pacific Ocean characterised by frequent earthquakes, volcanic activity and tectonic plate boundaries, especially subduction zones.

Q5. Why are stratovolcanoes generally capable of explosive eruptions?
Ans: Their viscous magma restricts the escape of gases. Pressure can therefore build up within the magma, increasing the possibility of explosive eruptions.