Krakatoa
The Indonesian volcano whose 1883 eruption was heard across the world
In the narrow Sunda Strait between Java and Sumatra sits a volcano whose name became a byword for cataclysm. Krakatoa erupted in 1883 with a violence almost beyond comprehension, blowing most of its own island apart and unleashing tsunamis that killed tens of thousands. The blast was heard nearly 5,000 kilometres away and ranks among the loudest sounds in recorded history. The island that exists today is largely a newcomer, a restless young cone called Anak Krakatau, the Child of Krakatoa, that has risen from the drowned caldera to continue its parent's work.
Krakatoa lies along the volcanic arc where the Indo-Australian plate plunges beneath the Eurasian, a subduction zone that makes Indonesia the most volcanically active nation on Earth. The 1883 eruption was a VEI-6 event that ejected some 20 cubic kilometres of rock and ash, collapsed the magma chamber, and left a submarine caldera where an island had stood. Ash reached the stratosphere and circled the globe, dimming sunlight and tinting sunsets a vivid red for years. Anak Krakatau emerged from the sea in 1927 and has grown intermittently since, reaching a few hundred metres before a 2018 flank collapse triggered another deadly tsunami.
The 1883 disaster arrived in a wired age, and telegraph cables carried news of it around the planet within hours, making Krakatoa arguably the first global media catastrophe. Its lingering atmospheric haze inspired blood-red skies that some scholars connect to the lurid backdrop of Edvard Munch's painting The Scream. For volcanologists it became a foundational case study in eruption dynamics, caldera collapse and volcanic tsunamis. Anak Krakatau remains closely watched, a living reminder that the strait is far from finished, even as fishing boats and tourists skirt its smouldering shore.