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REMEMBERING THE WHITE ISLAND ERUPTION

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.

Sources:

Titanic

Mount Pelee Erupts: 30,000 die

Remains of St. Pierre by Angelo Heilprin (United States, 1853-1907), 1902. Public Domain
Remains of St. Pierre by Angelo Heilprin (United States, 1853-1907), 1902.
Public Domain

On the lovely Caribbean island of Martinique, Mount Pelee erupted at 7:50 a.m. on 8 May 1902 killing 30,000 people most who were in the city of Saint-Pierre. Concern over the volcano had been growing due to is recent activity. In April explosions had begun at its summit. Numerous quakes, ash showers, and thick clouds of sulfurous gas affected the entire region. This caused many ground insects and snakes to come into Saint-Pierre causing serious problems for everyone and livestock. 50 people died from snakebites mostly children. As volcanic activity continued, water sources became contaminated with ash resulting in livestock dying. Outdoor activities near the mountain were cancelled and by May many were  worried. On 5 May, a crater gave way sending a torrent of scalding water and pyroclastic debris into a river and burying workers at a sugar works. The lahar (the name for such flows) was traveling 62 mph (100 kph)when it hit the sea causing a small tsunami to flood the low lying areas of Saint-Pierre. By 7 May things were getting worse with more ash clouds and glows of reddish-orange being seen from the craters at night.

Many began fleeing into the city (it was believed safe from lava flows)while many were trying to flee. Those that did leave would realize later how lucky they were.

A large black cloud composed of superheated gas, ash and rock rolled headlong down the south flank of Mt. Pelée at more than 100 miles per hour, its path directed by the V-shaped notch at the summit. In less than one minute it struck St. Pierre with hurricane force. The blast was powerful enough to carry a three-ton statue sixteen meters from its mount. One-meter-thick masonary walls were blown into rubble and support girders were mangled into twisted strands of metal. The searing heat of the cloud ignited huge bonfires. Thousands of barrels of rum stored in the city’s warehouses exploded, sending rivers of the flaming liquid through the streets and into the sea. The cloud continued to advanced over the harbor where it destroyed at least twenty ships anchored offshore. The hurricane force of the blast capsized the steamship Grappler, and its scorching heat set ablaze the American sailing ship Roraima, killing most of her passengers and crew. The Roraima had the misfortune of arriving only a few hours before the eruption. Those on on board could only watch in horror as the cloud descended on them after annihilating the city of St. Pierre. Of the 28,000 people in St. Pierre, there were only two known survivors.
(How Volcanoes Work: MT. PELÉE ERUPTION (1902),Geology Department,University of San Diego)

It was the largest loss of life due to a volcano in the 20th century. And the only volcano in French history to cause loss of life (Martinique is a department of France). The city of Saint-Pierre was no more. The French warship Suchet found mostly ruins and corpses. Anything in the direct path of the pyroclastic flow was destroyed completely (about 8 square miles). Outside of that zone the damage was less and more people survived. Another eruption on 20 May would obliterate what was left of Saint-Pierre killing 2,000 most of whom were rescuers, engineers and mariners. On 30 Aug another eruption occurred causing more fatalities and a tsunami. It was the last fatal eruption of Mount Pelee. It would erupt again in 1929 but authorities evacuated so no lives were lost.

The city of Saint-Pierre was never rebuilt and small villages now exists where it once did. Mount Pelee has been quiet but is under constant watch and considered an active volcano.