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They are, for many people, three of the least interesting-sounding words in the English language — monitoring, recording, and analysing.
But while they might not set your pulse racing or your imagination ablaze, the end result of those three rather colourless words is of vital importance to our homes, our communities and our endeavours.
The strongest, most robust, policies which protect life and livelihood are those based on the most accurate, carefully collected and up-to-date information.
In a country such as New Zealand, with its highly active environment and terrain, and a plethora of associated risks, we need to be confident our hazards modelling is among the best in the world.
Last week, possibly the most important such piece of work for New Zealanders was released publicly after more than two years of revision and recalculation.
Led by GNS Science, more than 50 local and overseas scientists have been working on an improved National Seismic Hazard Model, a crucial tool for estimating the likely severity of shaking from earthquakes anywhere in the country. Its findings will inform future building codes.
The model looks at all possible earthquakes which could affect a location and estimates the severity of the shaking they might cause.
It incorporates the data and knowledge from the Canterbury earthquakes of 2010-11 and the 2016 Kaikoura earthquake.
While it is good news we now have the most precise and current information on which to plan our future, the bad news is the model’s estimates of future shaking have risen across much of New Zealand, increasing by about 50%, on average, from the previous modelling, and more than doubling in some areas.
Here in the South we sit in a quieter part of the country seismically.
However, southerners should not be complacent, as there are still plenty of faults which could generate an earthquake which causes significant damage.
That includes, of course, the Alpine Fault, which runs down the western side of the main divide and is only around 50km from Queenstown and Wanaka, and the Akatore Fault just offshore of Dunedin and South Otago. The revised model also mentions the Dunstan and Hyde faults.
The new calculations conclude that shaking is forecast to be greater in the west of Otago, especially near the Alpine Fault, and that estimates of future likely shaking have doubled or more for some sites with specific soil horizons around both Dunedin and Queenstown.
The concepts involved in the modelling are complex, with words such as “risk”, “hazard”, “forecast” and similar all having specific meanings which may go beyond our usual understanding.
GNS Science seismologist Dr Matt Gerstenberger, who led the work, says New Zealanders should not fret that the Shaky Islands have suddenly become even more shaky, because the faults themselves have not changed.
What has changed is the level of understanding of these faults and how they may interact with the peculiarities of geography and the different kinds of ground around the country to produce shaking. The new model includes about another 25 years of figures, and also takes advantage of improved technology in being able to crunch these numbers.
One of Dr Gerstenberger’s key messages is that Kiwis should realise that an increase in shaking hazard does not necessarily mean the effect of that will be more damaging.
It is also a matter of proportion. Even places with a doubling or more of shaking hazard may still have a low overall hazard than other places.
That our scientists are working with experts from overseas to produce such robust models is extremely comforting.
There are too many people out there who rely on, or quote, a kind of science which is selective and not robust.
Just this week, Dunedin’s new mayor, Jules Radich, made and then retracted the astounding comment that the city had a very low rate of sea-level rise, “because the ocean’s quite cold”.
Work like the revised National Seismic Hazard Model may seem to some abstruse and irrelevant. But it is not.
It is absolutely vital to ensure we can safely continue living here and going about our daily affairs.
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