“The hard part is predicting when the source that generates a tsunami is going to happen,” he says.
“We pretty much have no idea because we have no way to forecast something like an earthquake, landslide or meteor impact … The impossible part is knowing when they’re going to happen, so you’re always in reaction mode.”
Borrero explains that the regions most at risk of a tsunami are those that lie astride the plate boundary between the Pacific and the Australian tectonic plates.
“Basically, from Kaikōura up to East Cape would be the number-one [biggest risk area]. The Hawke’s Bay, Gisborne region would have the highest risk because it sits right onshore from the subduction zone. The next-highest would be the east coast of the Coromandel, Auckland and Northland because they’re facing directly toward the subduction area.”
While recent alerts have not resulted in any large-scale damage, Borrero notes that New Zealand has seen the fury of a tsunami before.
“We do have the right types of geology to cause an extreme event, and they’ve happened in the recent past. In 1946, on the Gisborne coast, there was a 10-metre tsunami from an offshore earthquake that destroyed the Tatapouri Hotel. I now sometimes go to the Tatapouri Cafe over the weekend and say, ‘Well, it happened here.’”
So, has our public forgotten the gravity of this event and become complacent? How prepared is New Zealand for a catastrophic tsunami event? How great is the risk posed by the Pacific and tectonic plates? And should we be moving faster when it comes to gradual retreat from coastal dwellings?
Listen to the full episode of The Front Page podcast for a complete rundown on this issue.
The Front Page is a daily news podcast from the New Zealand Herald, available to listen to every weekday from 5am.
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