Reflections on the Boxing Day Tsunami

To say that the Boxing Day Tsunami had a huge impact is an understatement. It affected the world, the science community and me. My science training had not prepared me for the sheer devastation the earthquake and tsunami did across 19 countries. New Zealand was not immune to the devastation either; we lost seven kiwis that day. The total loss of life and damage is beyond comprehension. Today I reflect on the lessons we have learned as a science community to help ensure the loss of life and damage does not occur on that massive scale again.

What we couldn’t appreciate at the time was the Boxing Day tsunami was the start of a decade of deadly and destructive tsunami. These include the 2007 Solomon Islands (Gizo), 2009 Samoan Islands, 2010 Chilean, 2013 Solomon Islands (Temotu) Tsunami and, the largest of all in the Pacific, the 2011 Japan tsunami. All these events demonstrated the massive power of the mega-earthquakes which hugely displace the sea floor and sea water above causing tsunami.

So what have we learned in this decade of tsunami? Globally, we learned that we needed a much better tsunami warning capability. Before the 2004 Boxing Day tsunami, the Pacific Tsunami Warning and Mitigation System (PTWS) was the only tsunami warning system on the planet, but it is now one of four globally covering the world’s oceans. So at least we have learned that lesson.

In New Zealand, we have changed our tsunami warning system considerably. We now use tsunami forecast models to establish the potential threat in pre-defined coastal zones and issue this information in map and text formats. The threat levels can be used to inform evacuation decisions based on planned evacuation zones and routes. GNS Science act as the science advisors to the Ministry of Civil Defense and Emergency Management (MCDEM) employing forecast models and the expert knowledge of the “Tsunami Experts Panel”, a group of New Zealand based tsunami scientists.  

We also updated the science and technology in the wider Pacific; on 1 October this year PTWS improved its tsunami warning capability using similar techniques to those we currently employ in New Zealand. Now the Pacific Tsunami Warning Centre in Hawaii (the operational centre of PTWS) sends pictorial and text messages to member countries based on tsunami forecast models and the expected impacts on coastlines. This replaces the messaging based solely of the size and location of possible tsunami-generating earthquakes.

We have done a lot of work in the last decade. But here is what keeps me awake at night: we still rely totally on natural warnings (feeling high levels of, or long lasting shaking, and unusual sea behaviour) for local-source tsunami warning. These are the tsunami caused by earthquakes or triggered undersea landslides near our coast.  And there are some situations in New Zealand where a tsunami-causing earthquake may not be felt strongly, leaving a potential gap in our tsunami warning strategy. On the east coast of the North Island we have a huge fault (the subduction zone) where the Pacific tectonic plate meets and is pushed down below the Australian plate. This is similar to the tectonic situation off the coast of Japan. Many earthquake types can happen in this process, including “slow” earthquake which will not be strongly felt. And further north of New Zealand, a very large earthquake could send a tsunami towards cities and townships of the upper North Island without high levels of shaking being felt on-land (see 2013 GNS Science tsunami hazard update). Two “slow”earthquakes in 1947 caused tsunami which deposited seaweed in power line and damaged buildings, but thankfully caused no loss of life, in small communities north of Gisborne.

Work continues on the science and technology necessary to provide official warnings for these local events for New Zealand, which may provide minutes to 10s of minutes of warning. Watch this space!

I realise this sounds very “doomsday” scenario. And we haven’t been affected by a tsunami like this for a long time. But I’d like to see a local-source tsunami warning capability piloted here in New Zealand. I’m a realist and know the amount of resources required to make this happen.  But the Boxing Day tsunami taught me that the seemingly impossible can happen. We are more ready than we were in 2004. But we need to be even more ready than we currently are.

The most fundamental lesson we’ve learned though isn’t about science. It’s that people’s direct actions matter. The day may come when we have all the scientific systems set up, but we will always need to rely on ourselves and each other. If you feel a long or strong earthquake on the coast, evacuate immediately. Here is the best advice about evacuating during a tsunami (from the MCDEM):

·         Take your getaway kit with you if possible. Do not travel into the areas at risk to get your kit or belongings.

·         Take your pets with you if you can do so safely.

·         Move immediately to the nearest higher ground, or as far inland as you can. If evacuation maps are present, follow the routes shown.

·         Walk or bike if possible and drive only if essential. If driving, keep going once you are well outside the evacuation zone to allow room for others behind you.

·         If you cannot escape the tsunami, go to an upper storey of a sturdy building or climb onto a roof or up a tree, or grab a floating object and hang on until help arrives.

·         Boats are usually safer in water deeper than 20 metres than if they are on the shore. Move boats out to sea only if there is time and it is safe to do so.

·         Never go to the shore to watch for a tsunami. Stay away from at-risk areas until the official all-clear is given.

·         Listen to your local radio stations as emergency management officials will be broadcasting the most appropriate advice for your community and situation.

The Future of GeoNet Revisited - Part 1

Recently a reader of this blog asked me what more would GeoNet be able to do in 10 years’ time? At first I thought – what is he talking about - I answered that question in the GeoNet 2023 blog series (Part 1, Part 2, Part 3), didn’t I?  But he wasn’t meaning the technical details I had outlined, but what more would GeoNet be contributing to the wellbeing of New Zealanders and the wider world community? Or in current terms – how would GeoNet be helping to make communities more resilient (now that resilience is the new black, or is that orange)?

In 2001 GeoNet was brand new, and to me it still has much development ahead. But with a history approaching 15 years, we have to ask - what has been GeoNet’s major contribution, and where can we contribute more?

Nature was kind to GeoNet giving us all those years up to 2009 to develop the system before the largest and most prolonged series of geological hazards events in more than 80 years started. The period of “peace time” (for GeoNet and New Zealand) ended in 2009:

• 2009 (July): Dusky Sound Earthquake (M 7.8)
• 2009 (September): Samoan Islands Tsunami
• 2010 (February): Chile Tsunami
• 2010 (September): Darfield Earthquake (M 7.1)
• 2011 (February): Christchurch Earthquake (M 6.3)
• 2011 (March): Japan Tsunami
• 2011 (June): Canterbury Earthquake (M 6.3)
• 2011 (December): Canterbury Earthquakes (M 5.8, 5.9)
• 2012 (August, November): Tongariro Eruptions
• 2013 (July, August): Cook Strait Earthquakes (M 6.5, 6.6)
• 2014 (January): Eketahuna Earthquake (M 6.2)

During the period from 2009 until recently GeoNet transitioned from being a fast growing sensor network using many of the techniques of data handling and delivery developed earlier in the 2000s, to a powerful resource for emergency responders, scientists, engineers, the media and public. We embraced social media, mobile technology and our mission to inform.  We upgraded our earthquake analysis system while “under fire” from continuing Canterbury aftershocks, and continuously redeveloped our website and information delivery systems to cope with ever increasing load.

We became an example of a New Zealand high technology project which not only did not fail (almost an oxymoron), but also became an important part of the lives of many New Zealanders. And we did this within a fixed but flexible budget (and with the blessing of our sponsors, the Earthquake Commission - EQC) and without increasing staff numbers (in fact with a small reduction in total staff).

Our success has been highlighted by IT awards, and has been acknowledged by review panels and studies. For example the 2012 GeoNet Strategic Review panel concluded:

“GNS Science and EQC have worked together to develop a long-term, high-trust, mutually beneficial partnership. Together in GeoNet they have created a gem – a brilliant example of government agencies collaborating effectively together to create public value”

And similarly, to quote the recent EQC commissioned New Zealand Institute of Economic Research (NZIER) report "The value of information on natural hazards":

“GeoNet is now at the hub of a wider community of practice of researchers and users that extends well beyond GNS and EQC. This wider network, which GeoNet has enabled, has yielded direct but unforeseen benefits to New Zealand. For example, because of the quality of the GeoNet data infrastructure, New Zealand is able to leverage others research spending. Other geological agencies are doing detailed work in New Zealand. As one respondent observed ‘New Zealand is now the global geo-hazard laboratory for the world’”.

I believe we have achieved success because of our belief that what we do is important and this underpinned our dedication to providing data, information and insight to help New Zealanders respond to the unprecedented series of events we were facing.

But we achieved the required performance by delaying some equipment installations and replacements and redirecting resources, and sometimes by stopping doing some tasks and delivering some services. And often we did not introduce new products and services even when we knew they were or would soon be needed. This has left us in catch up mode, meaning sustaining GeoNet’s current level of performance and making sure data and information are made easily available must be one of our primary goals.

In the GeoNet 2023 blogs I was concentrating on the technology (one of my BIG interests), but in the next blog I will turn my attention to a more holistic view of how GeoNet can contribute even more in the future.