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.

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