A volcanic wake up call for New Zealand


In January 1991 I visited White Island volcano in the Bay of Plenty with my parents. It was an awesome yet surreal place, completely hostile to everything except a colony of birds living on its flanks and broken scrub in which they had made their homes. It helped to fuel a long standing interest in volcanoes and a desire to work on them. But nearly 29 years later in an eruption in broad daylight it has shown New Zealand and the world why volcanoes command respect.

The eruption at 1411 hours New Zealand time 09 December 2019 was tiny by global standards. It only lasted a few minutes, but in that time it has killed one person, injured 23 and left another 27 unaccounted for.

So, how did one small eruption that would probably have been forgotten by many by the end of the year except for the fact that it was lethal, manage to cause such grief? And how can this be prevented from happening again?

White Island is a volcano with a crater lake covering the main vent. Between the water and the magma below there is a layer of sediment that changes in chemical composition to almost crystallize and bound the debris covering the vent together. If the magma is at depth then fumarole activity will be lesser because the sealed vent provides less routes for the vapours to escape. As it rises the fumarole activity increases. Directly above the magma a mass of volcanic vapours rises towards the surface and as it pushes its way through the fluid saturated debris steam pressure builds. When the overhead mixture can no longer sustain the pressure it explodes.

Unfortunately eruptions through lakes tend to happen with quite short notice – only a few minutes in some cases, though the warning signs might be overt: seismic activity, a disturbance in the crater lake and increased venting. In the case of White Island where the boat/helicopter is some several hundred metres from the vent, even if they ran back, they might not make it before the explosion.

The explosion in a confined space can be devastating. A cloud of superheated rocks, mud and steam will expand at several hundred metres per second in all directions. If conditions permit a ground surge of falling debris will move across the crater floor and immediate surrounds at possibly over 100km/h. Whilst there are instances of people surviving such conditions, their injuries are likely to be acute. Based on the available footage of yesterday, that is what appears to have happened.

White Island, like New Zealand’s other volcanoes is monitored 24 hours a day 7 days a week by GeoNet, which has a network of seismometers, camera’s and other instruments in place. They provide real time seismic, photographic and other coverage of the volcanoes. Yesterday, just before the eruption, the GeoNet camera on White Island’s flank took an image that showed people on the crater floor perhaps 50-100 metres from the crater rim. The seismometer showed elevated activity that had been continuing for about three weeks was still happening. Last week a GeoNet statement said that it had entered a phase where an eruption should be considered possible.

Duty volcanologist for Institute of Geological and Nuclear Sciences (G.N.S.), which operate GeoNet, Brad Scott, has said that it is up to individual tour groups whether or not they operate from one day to the next. They operate through various alert levels. Hard hats, fully enclosed shoes and breathing masks are compulsory.

Over the next few days as the authorities piece together what happened, New Zealand will learn the story of how White Island caught authorities, tourist operators and locals alike off guard. But for now we focus on the survivors, those that are missing and those that were injured.

 

Is Nelson fire a sign of future


In the last several years there have been a number of increasingly damaging fires around New Zealand. Prolonged dry conditions, combined with excess vegetation growth that has not been checked, that is often quite flammable in nature can prove the perfect recipe for fires. The are a range of potential triggers ranging from sparks from trains going down railway tracks, farm machinery contacting stones whilst ploughing paddocks, burn offs gone wrong, not to mention human error or arson.

The Port Hills fire event of 2017 is the most destructive thus far in terms of property and lives lost with one person killed and 11 houses lost.

Following that event there was an inquiry into the fires and what could be learnt so as to prevent a repeat. Two years later with a much larger fire now threatening Wakefield, with a population of 2,500 near Nelson, three days after it started on a paddock in Pigeon Valley, how much have New Zealanders learnt and what has been done?

I asked this question a year ago in an earlier article. It found some basic problems with who was in charge when the fires started as they traversed numerous political boundaries. Depending on whose boundary it is in the nature of the likely response will change as different authorities will have different processes. There were also concerns with basic information flow between authorities and civilians, which meant some testy exchanges between the two parties.

Could a changing climate also have something to do with the potential danger posed by such fires? Whilst last year was very hot during summer, it was tempered by big and quite sudden swings to stormy weather with considerable rain in tow that kept the risk of drought and the subsequent risk of fire in check. In 2013 and 2017 when there were fire outbreaks that caused property loss, the damaging fires were caused by prolonged, intense dry warm weather with high sunshine hours. Coming out of a very wet 2018, few in November would have imagined that by the end of January parts of New Zealand would be a tinderbox, but that is what happened.

Questions around planning laws around what kind of vegetation should be permitted to grow were also raised. Around the Nelson and Tasman areas there is a range of temperate trees such as pinus radiata and eucalyptus, both of which have high natural oil content. At the time I mentioned that research into the suitability of different vegetation types had been conducted. For such vegetation to have a positive effect it needs to be planted on a large scale and not limited to a few homes. It might also be worthwhile having vegetation breaks where there are either no trees or vegetation or the vegetation is a belt of fire resistant species that are low in volatility when lit.

But the biggest concern was – and probably still is – how much planning pre-event has been done by regional, district or city councils to understand how this phenomena starts. Understanding it is but one aspect of the 4 R’s: Reduction, Readiness, Response, Recovery.

Putting that understanding to good effect by taking steps to mitigate the potential hazard is REDUCTION. Making sure emergency services and the authorities can be ready to move at short notice and encourage the public to have emergency survival plans and the necessary resources – food, water, medicine, clothes, transistor radio, torch with batteries and so forth – is READINESS. The execution of the plans and being able to adapt to circumstances on the day will determine the RESPONSE. Putting lives and communities back together and creating something approach as normal as possible is RECOVERY.

One year after the fires, what has New Zealand learnt?


The first I became aware of the fires on the Port Hills that started one year ago was a fellow staff member coming into the staff room and saying there is a big plume of smoke coming from the Port Hills and that it must be a scrub fire. Thinking it would probably be all over in a matter of hours I went out for a quick look and decided to have a closer look at coverage of it in the media later on. A year later, what have we learnt about fighting such fires?

For awhile an amalgamation of the New Zealand Fire Service and other emergency services has been on the cards. Whilst the individual organizations still exist as such, the umbrella organisation overlooking them has changed to Fire and Emergency New Zealand.

To the average person from one day to the next, that means little. One still obviously dials 111 for emergencies. The Police, Fire and St John still have their distinctive roles to play. What has changed is how events requiring an inter agency response are managed. Too late for the 11 houses that were destroyed in the fires last year, but hopefully not too late to prevent a repeat of such an event somewhere else in New Zealand.

When the fires started, the first on the scene were the Fire Service. But, although it was normally the first to respond to rural fires, the Fire Service jurisdiction lay within urban areas. In a rural fire event, the Fire Service would hand over to the Rural Fire Service when their personnel arrived. With 38 fire districts shared between the F.S. and the N.R.F.S., little wonder perhaps that confusion reigned. With these particular fires traversing the boundaries of Selwyn District, Christchurch City and Department of Conservation land, exactly who was in charge (or not in charge)of what, was a mystery.

People affected have complained of a lack of information being fed to them by Civil Defence or the Fire Service. A lack of intelligence meant when the forecast easterly change on Day 3 happened, the Selwyn District Civil Defence did not get it. Information about fire behaviour and progress all seemed to be missing. The Fire Service acknowledges this.

Whilst progress has been made addressing the command structure of the Fire Service, can the same be said for the replanting of the Port Hills areas burnt by the fire with less fire prone vegetation types. Carrying out this replanting using such vegetation types will help to reduce the risk to properties in the future.

It also raises questions about peoples preparedness for scrub fires that firefighters lose control of. Many people who were forced to move, were made to do so at short notice, meaning valuables, documents such as passports, driver licenses and so forth, ended up being left behind.

Finally one point of interest remains. If one looks at the Crimes Act provisions for arson, a person may be liable for up to 14 years imprisonment if they are found to have caused intentional damage by fire to property knowing a risk to life is likely to ensue; 7 years if found to have caused intentional damage by fire to property that they have no interest in. The Act says nothing about providing for someone found guilty of multiple instances in either case.

With warm weather forecast today, one hopes that fire wise it ends up being a damn sight less eventful than 13 February 2017 and the days following were.

The Emergency Mobile Alert


The Ministry of Civil Defence and Emergency Management is rolling out the Emergency Mobile Alert channel on 26 November 2017.

Between 1800 and 1900 hours that day (Sunday), phones capable of receiving an alert message will do so. This is expected to be about 1/3 of all New Zealand cellphone users and is forecast to rise substantially as people upgrade their phones. At the moment my own Huawei P8 Lite falls just outside the range of Huawei devices expected to receive the message.

This is all well and good, but whilst most of New Zealand will eventually be able to receive the messages, there is going to be – like there always has been – a small section of society for which this simply will not happen. Most of the people in this group will be elderly people with little or no social contact, who have not got a mobile phone and who are most likely not going to be familiar with the technology. Others will include new comers to New Zealand such as recent migrants, refugees and asylum seekers who might still be getting established, or who are established but use dumb phones. – ones that only receive basic text messages and calls.

The message will need to go out in multiple languages. Not everyone is going to understand what the emergency messages are about because of language barriers. If they do understand, they might not realize that it is just a test and not an actual emergency.

The message will also need to able to be made louder for hearing impaired, or visually improved for those with vision impairment.

But this new measure, welcome as it most certainly is, DOES NOT supercede taking action if you feel unsafe. The Civil Defence message for earthquakes where a tsunami might have been generated is still “Long and strong, GET GONE”. After a disaster has happened, there might be several hours lag time depending on the state of communications with affected areas before a warning can be issued. In the event of a near field tsunami generated just off the coast, that is too late.

So, I welcome the Civil Defence mobile test on Sunday night, but I want to see how they roll it out to other mobiles.