The 9 December 2019 White Island eruption was a steam-driven eruption, caused by the sudden expansion of magma-heated water into steam, which can occur at supersonic speed as the water expands into 1,700 times its original volume. Unlike magmatic eruptions, steam-driven eruptions usually happen suddenly and with little to no warning.
The expansion energy can shatter solid rock, excavate craters and eject rock fragments and ash out to hundreds of metres away from the vent. Violent ejections of hot blocks and ash, and the formation of hurricane-like currents of wet ash and coarse particles radiating from the explosion vent, can cause impact trauma, burns and respiratory injuries.
Cronin (2020a,b) has reviewed the circumstances surrounding this volcanic eruption. Forty-seven people were on Whakaari (White Island), located 52km offshore from Whakātane when the crater erupted on 9 December last year, showering tourists and guides with rocks, clouds of ash and toxic gases, killing 22 people and injuring 25. The victims were tourists and their guides on an adventure tourism visit to the island and the volcanic vent.
Many survivors suffered horrific burns and Ngāti Awa-owned tour operator White Island Tours came under scrutiny for continuing to run guided trips, even though GNS Science had raised its volcanic warning to alert level 2 two weeks earlier and banned its staff from going near vents a week before the eruption. It appears that even though the volcanic alert level had been raised to ‘unrest’ several days before the eruption, the visitors and their guides were unaware of the likelihood and consequences of an eruption. WorkSafe chief executive Phil Parkes said that those who went to the island did so with the reasonable expectation that there were appropriate systems in place to ensure they made it home healthy and safe.
WorkSafe has filed charges against 13 parties over the Whakaari (Worksafe, 2020). WorkSafe chief executive Phil Parkes said that no details of the investigation would be released to avoid compromising the court process, and he would not name any of the parties facing prosecutions over the tragedy. However, GNS Science, which is responsible for monitoring volcanic activity on the island, the National Emergency Management Agency (Civil Defence) and tour operators Volcanic Air and Ngāti Awa-owned White Island Tours have all confirmed they are facing charges. Parkes said the investigation did not consider the rescue and recovery of victims after the eruption, no enforcement action had been taken over those matters, and they would be the subject of other proceedings, such as a coronial inquest.
Ten parties have been charged under the Health and Safety at Work Act, nine under section 36 for failing to ensure the health and safety of workers and others, and one facing a charge as a person controlling a business. Each of these charges carries a maximum penalty of a fine of $1.5 million. Three individuals are also charged under section 44 of the act, which requires directors or individuals with the influence of a company to exercise due diligence that the company meets its health and safety obligations. Each charge carries a maximum fine of $300,000. The first court date is 15 December in the Auckland District Court.
White Island Tours has not publicly commented in any detail on its response, but Paul Quinn of Ngāti Awa Holdings previously told media that at level 3 alerts and above they liaised more directly with GNS, and that level 2 (which was the level at the time of the 9 December 2019 eruption) was still within operational guidelines. In a statement on its website, GNS Science said it had not yet been advised of the nature of the charges it was facing, and it would co-operate fully with the authorities while continuing its monitoring role.
Monitoring volcanic eruptions
New Zealand’s GeoNet is a network of monitoring instruments that measure miniscule earth movements continuously, and it delivers high-rate data from volcanoes, including Whakaari. However, it is not currently used as a real-time warning system for volcanic eruptions. Although aligned with international best practice, GeoNet’s current Volcano Alert Level (VAL) system is updated too slowly, because it relies mainly on expert judgement and consensus. Rather than estimating the probability of a future eruption, it gives a view of the state of the volcano in hindsight. All past eruptions at Whakaari occurred at alert levels 1 or 2 (unrest), and the level was then raised only after the event. The last five eruptions at Whakaari were not predicted, despite constant seismic monitoring over this time.
Dempsey and Cronin (2020) have developed an early warning system that, in retrospect, would have raised an alert for four of the last five major eruptions at Whakaari, and would have provided a 16-hour warning for the 2019 eruption. They have been operating this system for five months now, on a 24/7 basis, and are working with GNS Science on how best to integrate this to strengthen their existing protocols and provide more timely warnings at New Zealand volcanoes.
The way forward
In the current situation, fear of being held legally or socially culpable for well-intentioned but ultimately incorrect advice inhibits innovation and delays the implementation of new technologies. Priority should be given to developing a more proactive volcano warning system that operates in real time and is more physically based than the current volcanic alert level approach used widely around the world. We need implementation of new monitoring technologies like that of Dempsey and Cronin (2020), and the testing of physics-based methods of predicting eruptions. The prime minister’s chief science advisor, Juliet Gerrard, has issued a statement highlighting the importance of science advice in emergencies:
Attempts to limit access to science through institutional or other barriers and preventing scientists from giving their free and frank advice in emergency situations […] places a handicap on good decision making by our officials and politicians. Only by being able to access all the available knowledge, including its level of uncertainty and whether it is disputed, can decision makers effectively weigh up the possible consequences of the paths forward, guided by the best evidence.
We need to be much clearer on how volcanic hazard and risk are communicated to tourists, especially on volcanoes with a history of frequent eruptions.
For more information, go to www.riskfrontiers.com
- Cronin, Shane (2020a). Why White Island erupted and why there was no warning. https://theconversation.com/why-white-island-erupted-and-why-there-was-no-warning-128550
- Cronin, Shane (2020b). Scientists should welcome charges against agency over Whakaari White Island if it helps improve early warning systems. https://theconversation.com/scientists-should-welcome-charges-against-agency-over-whakaari-white-island-if-it-helps-improve-early-warning-systems-151174
- Dempsey, David and Shane Cronin (2020). New Zealand’s White Island is likely to erupt violently again but a new alert system could give hours of warning and save lives. https://theconversation.com/new-zealands-white-island-is-likely-to-erupt-violently-again-but-a-new-alert-system-could-give-hours-of-warning-and-save-lives-142656
- Gerrard, Juliet (2020). Reflection on science in emergencies. Office of the Prime Minister’s Chief Science Advisor. https://www.pmcsa.ac.nz/2020/11/30/reflection-on-science-in-emergencies-2/
- Volcano alert levels: www.geonet.org.nz/about/volcano/val
- Worksafe (2020). 13 parties charged by WorkSafe New Zealand over Whakaari/White Island tragedy. https://www.worksafe.govt.nz/about-us/news-and-media/13-parties-charged-by-worksafe-new-zealand-over-whakaariwhite-island-tragedy/