1883 eruption of Krakatoa

1883 eruption of Krakatoa
A lithograph of the eruption (circa 1888)
Volcano	Krakatoa caldera
Date	August 26–27, 1883
Type	Ultra Plinian
Location	Krakatoa archipelago 6°06′07″S 105°25′23″E / 6.102°S 105.423°E / -6.102; 105.423Coordinates: 6°06′07″S 105°25′23″E / 6.102°S 105.423°E / -6.102; 105.423
VEI	6
Impact	The final explosive eruption was heard 4,830 km (3,000 miles) away, caused at least 36,417 deaths; 20 million tons of sulfur released into the atmosphere; produced a volcanic winter (reducing worldwide temperatures by an average of 1.2 °C (2.2 °F) for five years)
A map of Krakatoa after the 1883 eruption, showing the change in geography.

The 1883 eruption of Krakatoa in the Dutch East Indies (now Indonesia) began in the afternoon of Sunday, August 26, 1883 (with origins as early as May of that year), and peaked in the late morning of Monday, August 27, when over 70% of the island and its surrounding archipelago were destroyed as it collapsed into a caldera. Additional seismic activity was reported to have continued until February 1884, though reports of seismic activity after October 1883 were later dismissed by Rogier Verbeek's investigation into the eruption. The 1883 eruption was one of the deadliest and most destructive volcanic events in recorded history. At least 36,417 deaths are attributed to the eruption and the tsunamis it created. Significant additional effects were also felt around the world in the days and weeks after the volcano's destruction.

In the years before the 1883 eruption, seismic activity around the Krakatoa volcano was intense, with earthquakes felt as far away as Australia. Beginning May 20, 1883, steam venting began to occur regularly from Perboewatan, the northernmost of the island's three cones. Eruptions of ash reached an estimated altitude of 6 km (20,000 ft) and explosions could be heard in New Batavia (Jakarta) 160 km (99 mi) away. Activity died down by the end of May, and there was no further recorded activity for several weeks.

Eruptions at Krakatoa started again around June 16, with loud explosions and a thick black cloud covering the islands for five days. On June 24, a prevailing east wind cleared the cloud, and two ash columns could be seen issuing from Krakatoa. The seat of the eruption is believed to have been a new vent or vents that formed between Perboewatan and Danan. The violence of the ongoing eruptions caused tides in the vicinity to be unusually high, and ships at anchor had to be moored with chains. Earthquakes were felt at Anyer, Banten, and ships began to report large pumice masses to the west in the Indian Ocean.