Vulkane.net presents Volcanoes

Krakatau (also called Krakatoa) is an island in the Sunda Strait between Sumatra and Java as well as the same-named the island group. This volcano subduction zone belongs to the Indonesian island ring and is highly explosive. Plinian eruptions, pyroclastic flows and minor strombolian eruptions with short lava flows are the frequent types of eruptions.

1883 Krakatau gained tragic notoriety when it self-destructed in a gigantic eruption. The blast of the explosion was heard more than 4800 kilometers away and is considered to be the loudest sound ever heard. Pyroclastic flows and tsunamis devastated large parts of Java and Sumatra and more than 36,400 people were victims of this disaster.

Krakatoa pictures

Since 1927 the new volcanic island Anak Krakatau has emerged in the place where once this part of the world was destroyed. The small volcanic island sank several times back into the depths of the ocean, consumed by the relentless surf. It was not until 1930 that the "Child of Krakatau" became a stable island on which new life could soon take hold.

In recent years Anak Krakatau's activity is characterized by strombolian eruptions; a short discharge of lava flows occur and an occasional volcanic eruption. In October 2007, the most recent eruption phase began: below the main crater at the 400-foot summit, a new crater blasted free. Since then, periods of increased activity persist. However, Anak Krakatau is not permanently active.

Recent eruptions of Krakatoa

Between 2007 and 2011 Anak Krakatau was very active. There were only relatively short periods of rest. After a few years the depression of 2007 was filled and the volcano rose again. In September 2012 the eruptions changed their character. An eruption began during which lava flows were promoted. They quickly reached the coast and let the island grow. A little later it became quiet around Anak Krakatau. It was not until the early summer of 2018 that there were increasing signs that the volcano would awaken again: new high-temperature fumaroles formed and seismic activity increased. The first ash eruptions occurred on 18 June. In the following months a broad spectrum of eruptive activity could be observed: strombolian eruptions and Vulcan explosions produced tephra. By October 2018, Anak Krakatau had gained considerable height. The island also grew in latitude. Lava flows reached the south coast and caused it to grow.

Collapse and tsunami of 2018

In December 2018 a new tragedy occurred in Krakatau. On December 22, a large part of Anak Krakatau collapsed. The landslide masses caused a tsunami, which sent an early warning to the coasts of the surrounding islands. At least 439 people died. The collapse occurred during a paroxysmal phase, of which there were 10 before.