10 December 2019

Resources for Whakaari/White Island eruption information

Posted by Jessica Ball

It’s been a rough week for New Zealanders, particularly those affected by the Whakaari/White Island eruption and those responding to it. I’d like to strongly urge anyone in the media to please defer your questions to the NZ experts when at all possible – and be patient with them. Tragic events like these also have a profound impact on the people who study and work at volcanoes, and they will be hurting as well as extremely busy.

A Kiwi friend was kind enough to compile these resources for me and anyone who can use them:


Geonet Update #5 (Wednesday 11 December)

The level of volcanic tremor continues to rise and there is medium likelihood of future eruptive activity in the next 24 hours. The Volcanic Alert Level remains at Level 3.

An eruption occurred at Whakaari/White Island at 2:11pm on Monday 9 December, unfortunately with tragic consequences. We express our ongoing sympathies with those families that continue to be affected.

Since our morning bulletin the level of volcanic tremor has continued to rise and is now at the highest level seen since the 2016 eruption.

Our interpretation of all our monitoring data to date, including yesterday’s gas flight is that shallow magma within the volcano is driving the tremor, gas flux, and jetting activity observed in the craters created during the eruption.

Earlier today we conducted an expert judgement and the result is that there is a medium likelihood (40-60% chance) of a future eruption within the next 24 hours.

There is an extremely low likelihood of any potential ash affecting the mainland, but people may smell gas, depending on the prevailing wind direction.

Our monitoring equipment continues to function and is providing us with continuous data on the volcano’s activity.

The Volcanic Alert Level remains at Level 3.

The Aviation Colour Code remains at Orange.

 

Geonet Update #3 (Tuesday 10 December)

Since this morning, the seismic activity has remained weak, yet we continue to see periodic steam and gas driven jetting from the active vent area. The Volcanic Alert Level remains at Level 3.

An eruption occurred at Whakaari/White Island at 14:11pm on Monday 9th December, unfortunately with tragic consequences. We express our sincere sympathies with those families affected.

Over the course of today, there are no substantial changes to report. Seismic activity remains weak and there has been no further eruptive activity. We continue to see localised steam and mud jetting from the active vent area.

Our monitoring equipment is functioning well, despite some sites being covered in ash. We successfully completed an airborne gas (CO2, H2S and SO2) survey and made observations of the vent area and eruption impacts. Results of the gas survey will be included in the next information update.

Over the next 24 hours we still estimate an equal likelihood of either no eruption or a smaller/similar sized eruption that would impact the main crater floor, based on our observations and measurements. There is a high level of uncertainty associated with this estimate and we are working to reduce that uncertainty. We also estimate the least likely scenario is a larger eruption. There is an extremely low likelihood of any ash impact to the mainland, but people may smell gas, depending on the prevailing wind direction.

Geonet Update #1 (Monday 9 December)

Information on the 09 December 2019 eruption of Whakaari/White Island

At ~14:11 NZDT, Whakaari/White Island, an active volcanic island approximately 50km from the mainland in the Bay of Plenty, New Zealand, experienced a short, intense eruption, sending a plume of volcanic ash 12,000ft into the sky. This type of eruption is not an altogether rare occurrence at New Zealand’s most active volcano. Unfortunately, approximately 47 people were visiting the island at the time of the eruption and in the immediate vicinity of the volcanic crater. At the time of writing, 5 people have been confirmed as having lost their life during the eruption while 8 remained unaccounted for, and 31 remained in hospitals around the New Zealand. The majority of those affected are foreign nationals and tourists.

In the coming days there will be an opportunity for reflection and questions but right now, the response is still very much active.

If anyone is concerned for family and friends that may have been on White Island at the time, if in New Zealand, they can contact the Police on 105. People overseas can call +64 9105 105, or use the online form on the Police and Red Cross websites below.

Published: Tue Dec 10 2019 4:30 PM

Following the 9 December devastating eruption at Whakaari/White Island we have put together some information about the island.

New Zealand’s most active volcano

Whakaari/White Island is currently New Zealand’s most active volcano, it has been since an eruptive episode started in 1976. It was in almost continuous eruption from 1976-2000 and numerous explosive eruptions impacted the entire Main Crater floor area. A second eruptive episode started in 2011 and continues today. Whakaari/White Island is a cone volcano and has built up a typical-looking volcanic cone from many small but locally significant eruptions over a long period. The cone rises about 900m above the local sea floor but most of the cone is below sea level.

Eruption styles at Whakaari/White Island

Whakaari/White Island is a wet volcano with a crater lake and typically has explosive eruptions. These occur with little-to-no warning, and often impact the Main Crater floor area. These explosions eject hot rocks (cannonball-like projectiles), ash clouds and surges (pyroclastic density currents).

What is a phreatic eruption?

A phreatic eruption is driven by superheated steam and gas. Often this steam and gas builds up behind a rock and mineral seal and when the strength of that seal is exceeded by the gas pressure, an explosive eruption can occur. The gas driving the eruption likely comes from a deeper source of magma, but the magma itself is not directly involved. Phreatic eruptions can also occur when hot magma comes into contact with cold ground water, but we don’t believe this is the situation at Whakaari/White Island.

Danger to coastal communities

Whakaari/White Island lies about 50 km from the North Island coast so there is an extremely low likelihood of any effects from the eruption on the mainland. If there were any effects, the most likely are fine ash falls (like pollen) and the smell of volcanic gas, which are more likely to just be a nuisance.

Communicating the volcano’s status

In New Zealand we use the NZ Volcanic Alert Level System to communicate the level of activity at the active volcanoes in New Zealand. Information about the level of activity is posted to our website, app and social media by way of Volcanic Alert Bulletins. The NZ Volcanic Alert Level System has 6 steps. Level 0 is a quiet volcano where no activity is occurring. Levels 1 and 2 relate to ‘volcanic unrest’, this is when we detect changes at the volcano (earthquakes, ground movement or gas emissions etc.) that indicate a change in status. This may be an increase or decrease in activity. Alert Levels 3, 4 and 5 relate to small, medium and large eruptions and the likely area affected. An eruption can occur from any level with no warning, and the levels may not move in sequence as activity can change rapidly.

Is it unusual to go from Level 2 to an eruption?

An eruption can occur at any Volcanic Alert Level (Level 1 or Level 2). There are also times when the volcano is raised to Level 2 with no subsequent eruption.

Past fatalities

In 1914 a landslide destroyed a mining village and killed 10 workers on the Main Crater floor. There was no eruption related to this landslide.

Eruption scenarios

Over the next 24 hours we estimate an equal likelihood of either no eruption or a smaller/similar sized eruption that would impact the Main Crater floor. There is a high level of uncertainty associated with this estimate. We also estimate that the least likely scenario is a larger eruption.

Current eruption information

  • Eruption occurred 2.11pm NZST 9 December 2019 – it was a short-lived event, of 1-2 minutes duration
  • The eruption has impacted the Main Crater floor area. Ash and debris cover the crater floor
  • The eruption created a steam and ash column to 12,000 ft (3-4km) above the island
  • We raised the Volcanic Alert Level to Level 2 from Level 1 on November 18 to reflect heightened activity at the island
  • Monitoring equipment on the island is still functional and providing near real time data
  • While we have seen a steady decline in activity, there remains significant uncertainty about any future activity
  • The Volcanic Alert Level remains at Volcanic Alert Level 3 (minor volcanic eruption)
  • During the eruption, the Volcanic Alert Level was at Level 4 (moderate volcanic eruption)
  • The Volcanic Alert Level relates only to volcanic activity, and not impact. Even small eruptions can have devastating impacts, as is the case with this eruption
  • We will continue to closely monitor Whakaari/White Island
  • GeoNet has been continuously monitoring Whakaari/White Island for many years. It is New Zealand’s most active volcano
  • GNS Science experts are providing update information to both national and regional responding agencies
  • GNS Science’s role is to advise responding stakeholder agencies
  • We are updating the public (and media) via Volcanic Alert Bulletins

Attributable to: Brad Scott, GNS Science Volcanologist

This is a short compendium of where you can go to for information.

For information on the eruption:
GNS Science through GeoNet the geological hazard monitoring agency
Web: http://www.geonet.org.nz
Facebook: https://www.facebook.com/geonetnz/
Twitter: @geonet
Media enquiries: +6473748211 or [email protected]

For information on the response to the eruption:
Bay of Plenty Emergency Management is the lead agency
Web: http://www.bopcivildefence.govt.nz/
Facebook: https://www.facebook.com/BOPCivilDefence/
Twitter: @BOPCivilDefence

The New Zealand Police are leading the search operation:
Web: https://www.police.govt.nz/major-events/whakaariwhite-island-eruption
Facebook: https://www.facebook.com/NZPolice
Twitter: @NZPolice

Media enquiries regarding the response to the event should be directed to the National Emergency Management Agency (until recently known as Civil Defence):
Web: http://www.nema.govt.nz/
Facebook: https://www.facebook.com/NZCivilDefence
Twitter: @NZcivildefence

The New Zealand Red Cross is working in conjunction with the New Zealand Police to maintain a register where people can mark themselves as safe or search for loved ones that may have been affected by the eruption:
https://familylinks.icrc.org/new-zealand/en/Pages/Home.aspx

Some information about Whakaari/White Island including some initial discussion on the types of eruptions that are experienced there:
https://www.geonet.org.nz/volcano/whiteisland
https://www.gns.cri.nz/Home/Learning/Science-Topics/Volcanoes/New-Zealand-Volcanoes/White-Island/About-White-Island
https://volcano.si.edu/volcano.cfm?vn=241040
http://theconversation.com/why-white-island-erupted-and-why-there-was-no-warning-128550

 

I will update this list as I’m able in the coming days.