Aotearoa New Zealand sits aside
tectonic plates and that puts the country at risk of earthquakes
Knowing how strong future earthquakes shaking might be
helps us to understand the risks to our communities.
The more we know, the better we can prepare, make good decisions,
and increase our resilience to earthquake hazard events.
And the world is continually learning with new information
resulting from every new earthquake event.
Developed using the best available science in the world,
the New Zealand National Seismic Hazard Model
is our future earthquake knowledge toolkit.
The National Seismic Hazard Model is a science
based, agreed estimate of the likelihood
and strength of earthquake shaking throughout New Zealand.
It's a detailed model to help decision makers manage
the risks, the losses due to earthquakes throughout New Zealand.
The New Zealand Seismic Hazard Model is an amalgam of many models.
It incorporates, I don't know, thousands of different models of earthquake
occurrence over different time frames, looking at it from different angles,
and it's all there to bring together the most comprehensive view
and understanding of earthquake occurrence throughout New Zealand.
So the national Seismic Hazard Model is a probabilistic model,
and why that's important is because it's not earthquake predictions.
We can't predict earthquakes.
We don't have the understanding to be able to do that.
So the reason it's probabilistic is because that's the way that we can
bring in a broad range of our scientific understanding
and put that into a form that can be understood
by others and used for decision making.
With this science New Zealand decision makers
such as the Ministry of Business, Innovation and Employment,
Toka Tū Ake EQC, local government and our emergency management agencies
can make informed decisions in our policy and practice.
The University of Canterbury is a major contributor
to the National Seismic Hazard Model project, along with many other
tertiary and crown research institutions in New Zealand
and in combination with a significant number of international partners.
We've learned significant new aspects of the earthquakes,
particularly on the backbone of the 2010 and 2011
Canterbury earthquakes as well as the 2016 Kaikoura earthquake.
Some of the important things that we've learned is increased
understanding of the nature of earthquakes and the complexity of earthquakes.
We saw in the Canterbury and Kaikoura earthquakes how individual
faults can connect together to cause complicated earthquake sequences,
and the new New Zealand National Seismic Hazard Model
has the ability to account for such complexity in earthquake occurrence.
It will lead to significant improvements in our ability
to forecast the nature and strength of earthquake induced ground motion shaking,
which will lead to more efficient design of societal infrastructure
so that we can find the right balance between upfront costs
to build resilience and the long term impacts of that resilience.
One of the big advantages that we have now
is the availability of high performance computing
and how we can run much more complex models than we could have done in the past
to account for many more things that are happening in the earth
and to account for much greater uncertainties.
We model
hundreds of thousands of potential earthquakes
around the country and these earthquakes
connect up different faults in the system and looks at how they may
interact together.
And there's the big ones, like
everybody knows about the Alpine fault, the Wellington fault,
and of course, the Hikurangi, which we've learned a lot about the subduction zone
in the last 10 or 20 years.
Those are those are big, important
earthquake sources for the future of New Zealand,
but there's also many other potential earthquake sources around the country.
One of the things that's been
quite important to us as we've been putting the model together,
is that anything we're doing, we want to make sure is openly available
to anyone who might want to use it or is interested in it or needs to use it.
So all of the outputs of the model, the model itself, all of that is
is easily available.
It's available online.
You can look at different maps.
You can look at special technical curves that engineers might be interested in.
There's a whole lot of different ways you can look at
what's come out of the model
and how that may be important to you and where you particularly live.
We've been working on the
seismic hazard model for a couple of years now.
It's involved a team of 50 or 60 scientists and engineers
nationally, internationally recognized, and that was super important,
so we could enfold, we can take on board scientific understanding
throughout the globe on how it impacts
our assessment of ground shaking throughout New Zealand.
Knowing as much as we can about earthquake hazards and risk
is only one part of New Zealand's safety plan.
The next is integrating that knowledge with the people
who can use that information.
Estimating the likely impact
of future earthquakes on New Zealand land, buildings, infrastructure
and people is essential to help us be as safe
and as prepared as we can be.