The eruption of Krakatoa, and subsequent phenomena. Report of the Krakatoa Committee of the Royal Society (London, Trubner & Co., 1888) Public Domain
On 20 May 1883, Krakatau(Krakatoa)–a small volcanic island west of Sumatra in Indonesia–came alive with an eruption noticed by a passing German warship. Other eruptions would be noticed by commercial liners and those living on nearby islands for the next two months. Then on 26 Aug an enormous blast took place that destroyed nearly two-thirds of the island. Pyroclastic flows and huge tsunamis would sweep over nearby islands and coastlines. But the worst came the following morning, At 05:30 am four eruptions would took place with the resulting sound heard over 3,000 miles away. Ash was propelled fifty miles into the air and would circulate around the globe creating colorful sunsets but also lowering temperatures worldwide by several degrees.
36,000 deaths resulted from the eruption and 31,000 were from the tsunamis created when much of the island fell into the water. The highest waves were 120 feet high when they washed over neighboring islands stripping them of people and vegetation. Pyroclastic flows that stretched as far as 40 miles claimed about 4,500.
The Krakatau eruption of 1883 is considered one of the most violent volcanic activities in modern times and even recorded history. However volcanic activity continues in that area. In 1927, a submarine lava dome was detected in the area that had been destroyed by the eruption in 1883. A new island volcano began to emerge spewing ash. Other islands also started appearing as well but eroded away by the sea. Ultimately a fourth one appeared in August 1930 and was able to last. It was named Anak Krakatau and continues to grow taller each year. It is an active volcano and seemed similar to Stromboli in its eruptions. However more recent eruptions have resulted in volcanologists to warning people to keep a safe distance away. And more ominous is that a large lava dome is growing in its crater. Signs point to one day a very explosive event occurring at this volcano.
View of the 2019 Whakaari / White Island eruption from Whakatane at 14:20 Source: Geonet
On 19 December 2020 at 2:11 pm local time the volcanic island of Whakaari/White Island, located in New Zealand’s Bay of Plenty, erupted. The eruption was classified as a phreatic eruption, an eruption of steam, water, ash, rock, and volcano bombs. Such eruptions can also produce deadly gasses which, if in sufficient amounts, can result in asphyxiation. 47 people were on the island at the time as part of tour groups visiting that day. 21 would die and two bodies initially found were likely swept into the sea by rains.
The island itself is remarkable. What you see is the top of a stratovolcano as nearly the entire volcano is underwater. As one of New Zealand’s most active volcanoes, it offers the opportunity to see its crater up close. Over the years it has had frequent eruptions sending ash and gas plumes high into the sky. Lava bombs from eruptions tossed into the bay can be seen glowing red at night. The island itself is uninhabited (there were some sulfur operations in the distant past but those are long since abandoned). The other item of note is that the island is one of the main breeding colonies for Australasian gannets.
Geonet had raised the alert for the volcano to Level 2 meaning that an eruption was possible. White Island Tours informed of this on its website and at the embarkation point. Royal Caribbean Ovation of the Seas also had a tour to the island that day. However it appears they did not notify those who signed up for the tour of this warning. Legal action by families of those who died as part of the Royal Caribbean tour in the eruption is underway.
Currently there are no tours to the island and even aerial tours are restricted at this time. The island is still classified as being in Level 2 according the latest bulletin on Geonet.
Results from the most recent gas flight on Wednesday 27 May indicate an increased gas flux since the previous flight on 20 May. While previous observations indicated a trend back to levels that are typical for this volcano, the recent increase in SO2 and CO2 gas flux, one of our main indicators of volcanic unrest, could be attributed to a new batch of the magma beneath the volcano at shallow depth.
Such eruptions are unpredictable according to most experts. There is no hard and fast way to say they will erupt. It is like pressure cooker that once it reaches that critical point bursts quickly and without warning. It happens with such speed that if you are too close to it, you probably will have little chance to react. On a small volcanic island like this one, vents are common.
The actions of White Island Tour boats and the helicopter pilots were remarkable. After the eruption subsided, White Island sent in its inflatables to get people off the nearby jetty. Helicopters arrived on the island to pick up survivors and carry them back as well. Their actions saved lives and will be long remembered by the survivors.
Vesuvius from Portici by Joseph Wright of Derby(1734–1797) Image:Public Domain
On 24 August 79 AD, one of the most destructive volcanic eruptions occurred in ancient history. Located in the Campania region in the Bay of Naples, the ancient city of Pompeii and those who lived around it never saw Mount Vesuvius as a threat. Their knowledge of volcanoes was limited and it had not erupted dangerously in recent memory so its dangerous past was unknown to them. As one expert put it, this volcano is a low frequency high impact one.
Pompeii
In 79 AD Pompeii was not unlike a vacation resort we know today. Wealthy Romans vacationed here and built beautiful houses and villas. Locals benefited as it meant these Romans were willing to spend money on fine foods and all kinds of other luxuries. Shops, cafes, taverns and other places flourished from the tourists who came and stayed a while. With open area squares and marketplaces, it was a busy place. It is estimated by scholars that up to 20,000 people lived here in 79 AD. In 63 AD, Pompeii and Herculaneum were shaken badly by an earthquake that damaged many houses and damaged infrastructure. Excavations have shown that by 79 AD they were still repairing the damage done from that earthquake. And that more recent ones had occurred as well.
The Last Day of Pompeii by Karl Bryullov (1799–1852) Google Art Project Public Domain
The Eruption of 79 AD
It was a normal day like any other. The occasional rumbles from the mountain had not particularly alarmed anyone. Around noon on 24 August 79 things changed forever. Mt.Vesuvius erupted with a massive 10 mile mushroom cloud sent into the stratosphere. All the ash and pumice would rain down over the area for the next twelve hours. At this stage it was still possible for those who could to flee. Those who remained would see it get steadily worse. Night would become day. Hot ash and pumice would fall continuously causing buildings to collapse from its weight. It became terribly difficult to breathe as well. The next morning the dawn would not be seen. And early in the morning of 25 Aug, a pyroclastic surge swept through the area. This superheated poison gas and pulverized rock traveled over 100 miles per hour. Unless you were outside the radius of the surge or deep underground, it would kill you. By the time the volcano subsided the next day, Pompeii and Herculaneum were covered completely by volcanic ash as was another town Stabiae. Those who came back to find relatives or view the scene were startled. The cities were completely buried and would remain so until the first excavations in 1748.
Pliny The Younger, staying west across the Bay of Naples, recorded what he saw in two letters he sent to Tacitus. Sadly his uncle, Pliny the Elder, would perish when he went over in his boats to Stabiae. Pliny wrote the eruption lasted eighteen hours with Pompeii buried under 14-17 feet of ash and pumice.
Vesuvius has erupted many times since. The most catastrophic one was in 1631 where it destroyed many villages under lava flows and 3,000 people died. Its last major eruption was in March 1944 and destroyed several small villages with lava. The eruption was seen from Naples and damaged (thanks to hot ash and other things)or destroyed up to 88 B-25 medium bombers based in Terzigno, Italy. The volcano is kept under constant watch to prevent anything on the scale of the eruption of 79 AD to the people who live under its shadow.
Pompeii, with Vesuvius towering above.(2010) Author: Qfl247 (Wikimedia Commons)
Significant excavations beginning in 1927 have revealed much of what life must have been like before the destruction. More somber were the finding of some 2,000 bodies. Volcanic ash hardened and preserved the outlines of their bodies. Once the flesh had gone, the outline remained but filled in with plaster revealed those final moments of their lives. Many of the homes that have been excavated display much of how the wealthy lived in Pompeii. Ironically the city was built with materials from the last catastrophic earthquake called Avellino Eruption that occurred during the Bronze Age.
