“No duff!” Exercise Tangaroa and the very real M5.7 earthquake off Te Araroa

“Now, as I was saying about the tsunami…” (BLEEP BLEEP BLEEP!)

One of the screens at the GeoNet Media Centre begins flashing bright red and making loud bleeping noises. Dr. Gill Jolly, one of our science leaders, stops to take a look over her shoulder to see what is going on, as we all do, a bit breathlessly.  Red beeping screens usually doesn’t mean hugs and puppies at GeoNet. We wait for the red square to appear on the screen of the world map. It is near New Britain, a large island in Papua New Guinea.  We wait for the magnitude numbers to come up; an initial M6.7.  Our duty officer walks calmly back to his computer to check if it could cause an actual tsunami, rather than the one we are all exercising. The words are spoken “No Duff”.

I’ve worked in or around Civil Defence organisations for over a decade and rarely are the words “no duff” spoken in an exercise. "No duff" means that something real is happening and we need to pause the exercise to respond. Our duty officer returns quickly with the news that, while the earthquake was large, it won’t directly affect New Zealand. We get back to the exercise at hand: the national tsunami Exercise Tangaroa.  

Working in Civil Defence Emergency Management exercises can be a strange experience for the uninitiated. There are all kinds of specific terms and acronyms used like CIMS (Coordinated Incident Management System), EOC (Emergency Operation Centre), and CDEM (Civil Defence and Emergency Management). There is good reason for all the acronyms; Civil Defence has developed, partially, out of a military heritage from post-World War 2 and the use of these acronyms helps generate a shared understanding as well as being able to work at speed. But Civil Defence has evolved well past its post WW2 roots; it is now a coordinated group of all first response agencies (Police, Fire, Ambulance) combined with Health, welfare agencies (Red Cross, Salvation Army etc…), lifelines (water, electricity, transport and gas providers) and the coordinating agencies; the local, regional (CDEM groups) and national (Ministry of Civil Defence and Emergency Management). The CDEM structure also includes GeoNet and GNS Science, to provide science advice and information to the responding agencies, specifically MCDEM. And, while CDEM focuses its exercises on agencies, everyone is needed to respond effectively, as seen in Christchurch with the Student Army. 

Exercise Tangaroa was a scenario of a large tsunami (M9.1) located in the Kermadec Islands, slightly out of the coverage of the GeoNet sensor network (the writers of exercises can be mean sometimes!). As a regional source tsunami, it means we have little time to determine its impacts before the tsunami hits our shores, unlike the distant source tsunami, where CDEM agencies get hours to carefully plan if evacuations are necessary. However, we still have a role to play in bringing together the Tsunami Experts’ Panel, a group of expert volunteers who assist MCDEM in understanding what the possibility of tsunami impacts are after a large earthquake off the New Zealand coastline.  Exercises are always pretty stressful affairs, with miscommunication, misdirection, rumours and systems barely holding up under the pressure. But this is the value of exercising; to see where the gaps are so we can better plan for when the real thing happens. It is stressful, even notionally, working to respond to a pretend tsunami that could have such damaging affects to the people of New Zealand.

Needless to say, we were all pretty tired after Exercise Tangaroa. Imagine our unpleasant surprise when our system detected a large earthquake off the coast of Te Araroa this morning. Our seemingly tireless duty officer sprang into action, shaking off any stress from the day before and quickly refined the earthquake's depth and location. Our duty officer provided us with what we needed; more clarity on the location than our automated system provides. After a brief flurry of media phone calls and social media questions, we have a cup of coffee together, take a breath and prepare ourselves for what Mother Nature may have in store for us next. 

It is something I’m always being reminded of at GeoNet. Exercising is somewhat reassuring because at least you are aware of when it is coming. In real life, we get no such warning. We don’t know when a damaging tsunami may strike our shores but, if the past is any indicator, we should be as prepared as we can be.

One of our partners, MCDEM (the people who ran Exercise Tangaroa) have put together a great website that can help you prepare for all kinds of emergencies, not just tsunami:


Why is New Zealand so shaky?


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