Editorial: Tsunami reaction not good enough

For a few hours on Wednesday morning New Zealand faced a civil emergency. The earthquake southeast of Samoa at 6.48am NZT had been big enough and shallow enough to heave up an ocean tsunami that had hit Samoan coastal settlements and would also be coming this way.

A tsunami is possibly the most likely natural event that could cause death and destruction around this country. We lie in vast oceans. Turn the globe until New Zealand is nearest the eye and Australia and Antarctica are almost the only other land masses to be seen in a hemisphere of sea.

Our position is both a threat and a benefit. The threat lies in exposure to possible tsunami from seismic activity anywhere in the Pacific or the Southern Ocean. The benefit comes from the distance that the ocean wave would probably have to travel. If it originated near South America we could have 12 hours' warning. On Wednesday we had three hours, which should be plenty of time to gauge the wave and the extent of its possible impact, warn people in exposed places and tell them precisely where to go for safety.

Of all potential disasters, tsunami should find our civil defence well organised and effective. Was it so on Wednesday?

When word circulates of something like this people turn on radios and televisions expecting to hear the information they need. Those who turned to TVNZ's Breakfast programme on Wednesday saw the host telling a Civil Defence spokesman the tsunami in Samoa was no mere "rumour" as the spokesman was calling it, the waves had hit.

Organisational lines of communication seemed to be better than the public information. Warnings were relayed to local emergency services early in the morning and people were advised to leave beaches in good time.

Some ignored the warnings, of course, and some sightseers went down to the beaches. Why anyone would stand in a spot where they are likely to see either nothing or the last thing they will see is beyond rational explanation. Civil Defence cannot save people from themselves.

Public information at these times is as important as organisation. If local Civil Defence precautions were being taken on Wednesday, there was not much effort to keep the public informed. News services did their best but what people needed to hear were regular, calm assessments of the approaching risk and reassurance that those in vulnerable places would be alerted in good time, told what to do and where to go.

Effective Civil Defence has to be unconcerned that it could be accused of needless alarm by people wise after the event.

Wednesday was a cause for alarm and sirens were sounded in some places but on the whole the system seems to have erred on the side of caution.

It described the expected sea rise as a wave of one metre, which sounded to surfers like a wave they could ride, and some went out. A tsunami is not a vertical wave, it is a speeding slope of water, mostly below the sea surface, that hits a rising seabed and rears up to break in greater force over the land in its way.

Fortunately the energy of the Samoan tsunami had dissipated to barely a ripple on New Zealand's coasts but nobody was to know until it arrived. Technology these days surely permits more accurate monitoring of a phenomenon that must be visible to satellites and easily measured by strategically placed buoys.

Civil Defence always vows to learn from events such as this but it should not need the reminder they bring. A tsunami is a coincidence of many forces, geological and oceanographic, but once one starts it is possible to see it coming.

A country in our position should be better prepared than anywhere.