In 1883 the small volcanic island of Krakatoa in Indonesia, exploded with a force 13,000 times greater than the atomic bomb dropped on Hiroshima, Japan, during World War II. Although not considered the deadliest eruption in recorded history, it was the first natural disaster that was felt worldwide and whose cause was known. The majority of the island itself disappeared beneath the sea. Here’s what happened to it.
Location: Krakatoa is located in the Sundra Strait in Indonesia between the larger islands of Sumatra to the west, and Java to the east. It is one of about 130 active volcanoes in Indonesia. Technically it is a caldera that was created by the 1883 eruption that caused most of the island to collapse into the sea after the magma chamber emptied. The caldera was formed from the Krakatoa archipelago that consisted of four islands: two were remnants of earlier eruptions, a third is the remnant of the 1883 eruption, and a fourth island that emerged from the caldera in 1927. Krakatoa was 5.6 miles long and 3.1 miles wide at the time of the 1883 eruption. It had three volcanic cones.
Pre 1883 History: A 19th century compilation of oral traditions of the Javanese people records that a major eruption on Krakatoa took place as far back as 416 AD. However, historians have been unable to confirm the eruption, and there is no geological evidence to support it. Records have emerged from Java’s Sailendra dynasty that point to seven separate eruptions on Krakatoa that occurred between 850 and 1530 AD. In 1679, a Dutch mining engineer sailed through the strait and observed that Krakatoa was an island covered with trees, but when he returned two years later, he recorded in his diary that the island was completely burnt out. The captain of his ship stated that an eruption had taken place the previous year. In 1780, two ships from Captain Cook’s third voyage, HMS Discovery and HMS Resolution, passed through the strait on their return to Britain and stopped at Krakatoa. They discovered that the island was lush with foliage, had fresh water, and a hot spring. Further, the natives were friendly and hospitable. On September 8, 1832, the USS Peacock, paid a visit to two of the islands in search of provisions and found much foliage, but no provisions or fresh water. In July, 1880, a Dutch geologist named Rogier Verbeek made an official survey of the islands, but was limited in scope as he only was allowed to spend a few hours collecting samples.
The Big Blast: On May 20, 1883, a German warship passed through the strait and reported seeing a seven-mile high cloud of dust and ash rising over Krakatoa. In the ensuing months similar seismic activity was observed by commercial ships as well as natives on Java and Sumatra. On August 26, a massive explosion occurred that resulted in about two-thirds of Krakatoa being destroyed. A day later, four more huge explosions took place. They were so violent they could be heard as far as 3,000 miles away. It is reported that anyone within ten miles of the explosions would have had their eardrums blown out. The third explosion on August 27 was the most violent, and the pressure wave was recorded by barometric pressure devices around the world. Some barographs recorded the pressure wave changing direction to and from the volcano six times over the next several days. It rounded the earth’s circumference three and a half times. The explosions lifted five cubic miles of earth as high as fifty miles into the atmosphere. The volcanic ash that deposited in the immediate area created two temporary islands and temporarily increased the perimeter of the surviving land mass.
Level of Destruction: The eruptions caused huge devastating pyroclastic flows, a fast-moving cloud of gas and volcanic matter, as well as numerous tsunamis. The pyroclastic flows in particular were deadly as they roared out at a high rate of speed, killing and flattening anything in their path for a distance of up to forty miles. The Dutch Authorities put the death toll at 36,417, but other sources claim it was as high as 120,000. Tsunamis measuring up to 120 feet high were responsible for the majority of the deaths. They ripped over nearby islands washing away vegetation and carrying people out to sea. Up to a year afterward reports of human skeletons floating on rafts of volcanic pumice were reported as having washed up on the east coast of Africa. The average summer temperature in the Northern Hemisphere the following year fell by 0.72 degrees Fahrenheit. Spectacular sunsets were reported in most parts of the world for up to a year after the blasts.
Conclusions: Owing to the rise of transoceanic communications cables, the volcanic eruption and explosion of Krakatoa was the first natural disaster that was felt and understood all around the world. It may have marked the birth of the era of global awareness that has parlayed today into what is referred to as global warming.
Sources: History.com, Krakatoa Explodes, August 27th, 2021.
Wikipedia, Krakatoa.
Great article Dave
Glad you like it Russ.