New Zealand - Their volcanoes are more unpredictable than we ever realised, new research reveals. Ruapehu, White Island, Tongariro, Auckland . . . the whole North Island is a tin lid clipped atop a pressure cooker, as shown by this week's eruptions. So why are they still so complacent - and why is the property around Auckland's volcanic cones still the most valuable in the country?
Mt Tongariro rumbled into life at 11.50pm on Monday, throwing ash and rock a kilometre into the air, sparking a potential threat warning for Central North Island regions. "The sky lit up like a big flash of lightning followed by a huge grumbling noise. Then I saw a large black cloud appear near the mountain. I assumed it was a bad storm, so went in and went straight back to bed."
It was nothing, really, said a resident. Nothing, when hectares of farmland are coated in ash. Nothing, when boulders smash through the roof, water tank and beds in Ketetahi Springs Hut. Nothing, when flights in and out of the east side of the North Island are shut down. Maybe it's because they're such a famously stoic people, but would the people of any other nation describe such an eruption as "nothing, really"? "Stoic" is the generous description. A more accurate one might be "complacent".
New research by Devora (Determining Volcanic Risk in Auckland), a multi-agency project to determine Auckland's volcanic risk, has discovered previously unknown levels of volatility in this country's volcanoes. This heightened risk, disclosed by Devora project team leaders on Sunday, should be a wake-up call to Aucklanders, in particular. The research shows there has been a lot more volcanic activity in the past than first thought, meaning the country's volcanoes, especially around Auckland, could be more unpredictable than previously believed.
Next month, a Civil Defence exercise will try to shock New Zealand into action by enlisting a million people - at home, work and school - to participate in the world's first nationwide earthquake drill beginning at 9.26am on September 26. "It's the kids we really have to get through to from an early age, so awareness and preparation for a major national disaster comes almost second nature and is passed to future generations."
New Zealand's varied landscape and its towering mountain peaks owe a lot to the tectonic uplift of land and volcanic eruptions caused by the Pacific and Indo-Australian Plates clashing beneath the Earth's surface, which has left parts of the country seismically active. The world's most dramatic volcanic eruption in 5000 years occurred here about 200AD. The Taupo eruption devastated much of the central North Island, emptying Lake Taupo in the process. Since Maori first settled here, they have seen volcanoes Tarawera, Rangitoto, Taranaki, Tongariro, Ngauruhoe, Ruapehu and White Island intermittently and unpredictably spew out fountains of hot ash or lava.
The once-dazzling pink and white terraces on the shores of Lake Rotomahana were New Zealand's greatest national treasure. They were cherished by Maori and known far and wide as the eighth natural wonder of the world. Then, during an immense volcanic eruption in 1886, they disappeared. They now lie below the lake. Mt Ruapehu erupted most recently in 1995 and 1996. Mud flowed through the Whakapapa ski field and the slopes of the mountain were coated with volcanic ash.
Auckland, a city of 1.4 million people, sits uneasily atop more than 50 volcanic cones. A volcanic eruption in Auckland in the next 50 years has about a 4 per cent likelihood, although "considerable uncertainty surrounds this figure". Last year, four new volcanic craters were discovered underneath South Auckland, bringing the total number of volcanoes in the Auckland volcanic field to 55. The most prominent of the new finds is a 300m diameter crater surrounded by a semicircular rim of volcanic ash. "There are a number of other places in the world with volcanic fields, the difference is none has a city the size of Auckland built on them."
Previously undiscovered layers of ash found under the lakes from other volcanoes further south, including Taupo, Okataina and Tongariro, suggest that New Zealand has undergone more volcanic activity than first believed. This raises questions about the future volatility of all Auckland's volcanoes. Worse case scenarios for the city include Rangitoto Island blowing apart, vapourising everything in its path, or cones the size of Mt Eden bursting out in Queen St, uprooting buildings and destroying infrastructure. If magma was to travel 80km to the surface and hit sea water, the eruption would create a catastrophic explosion. "There would be clouds of hot ash and steam. It would be a very significant event."
An eruption in the city centre could be just as devastating. "If the magma kept coming and there was enough of it, it could produce a scoria cone as big as Mt Wellington in the heart of the Central Business District." New findings showing Rangitoto is likely to have erupted more often than first thought. "We used to think that a volcano wouldn't erupt twice but now we know that might not be the case. Imagine if a volcano the size of Rangitoto popped up in downtown Auckland? That could happen, because it has happened in the past. "And who knows when the next one would be-it could be next week or in a thousand years. That is just the way it is."
Despite the large number of volcanoes in Auckland, they believe the field is currently stable and a greater threat to the city is likely to come from the fallout from a large eruption in the central North Island or elsewhere. "In Chile, I saw the damage volcanic ash can do from the eruption there last year. If the same thing was to happen in New Zealand it would be catastrophic. Cities and towns would grind to a halt, waterways would be clogged up and the land that livestock feeds on would be so badly affected thousands of animals would die from starvation or poisoning."
If an eruption the size of this week's one occurred in Auckland, the chaos would be immense. "Depending on the time of day, up to half a million people would be evacuated to outside of a 5km exclusion zone..."How long it would take to recover economically from something like that is anyone's guess." Most deaths or injuries would likely be caused by people refusing to leave the area or their homes. "History shows that this has been the case in a lot of major evacuations around the world. Hurricane Katrina in the United States a few years back was one of the best-managed evacuations ever, but there was still a lot of casualties from people who just wouldn't budge. And you can't force them."
One Auckland University student has his bags packed . His car at home is loaded with emergency equipment, including food, water, torches, batteries and a tent. He is ready to meet members of his family at a prearranged spot for them to escape the city as quickly as possible following an unexpected volcanic eruption. He has prepared a DIY emergency plan to follow in case of a major event. "I have taken a first-aid course and learned some survival techniques. I also have developed a habit of keeping my car topped up with petrol." He says people are all talk but no action and he is worried by their complacency. He is so concerned about volcanoes going off he tried to form a survivalist group. He was disappointed there were no takers.
Frustratingly, little has been learned from the deadly earthquake in Christchurch. "Our latest research shows Aucklanders are the least prepared in the country. It is great they feel they live in a safe place but because of the number of volcanoes it is not wise to simply ignore planning what you would do if a natural catastrophic occurred. They seem to think they are in a place with plenty of resources and nothing will happen to them... People in Christchurch and Wellington are twice as well prepared as Aucklanders."
Auckland does not look like a city built on a volcano. The views and lush plant growth afforded by the volcanic cones make them some of the city's most lucrative real estate. Real estate firms say people are even battling to buy in volcanic hot spots. Interest in such areas has never been higher and people are still prepared to pay top dollar to be in the zones for the best grammar schools. House values in Auckland are still soaring. Prices rose 3.1 per cent in the three months just gone, with an average sale price of $656,846. Values are up 6.3 per cent on an annual basis.
"It is a worry when people's safety plan is based on not being prepared. It is perhaps even timely that the eruption happened in Tongariro and that no one was hurt or extensive damage done. It will perhaps remind people about the importance of being prepared through joining the Shake-Out event and getting up to a million people participating in practising 'Drop, Cover, Hold'. Some people in Auckland might think this is only relevant for earthquakes but you have to remember that any volcanic eruption in the Auckland region would be preceded by a series of quakes anyway."
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