Quake shows need to adjust tsunami zones

The magnitude-7.9 quake generated mere ripples here, 8 inches in Hilo Harbor and about 1.5 feet in Kahului Harbor. But the waves were large enough to show that quakes from areas south and west of Hawaii can send tsunamis to our shores.

As a result, scientists are reviewing inundation and evacuation zones, weighing the threat of seismic waves from regions that had not been considered previously. Current danger zones, which already were being revised, had been established contingent on tsunamis generated from earthquakes to the north and east of the islands where destructive waves historically have originated.

The Tonga quake, which caused little damage and no loss of life, enables scientists to compare data from a real event to existing computer models to better predict events in more severe earthquakes. It gave the Pacific Tsunami Warning Center in Ewa Beach a dry run of operations, and a chance to fix some problems it found in warning procedures.

The center also is considering whether to include the news media on warning lists, which could prove helpful in getting word out to residents, but policies will need to be outlined for maximum effect.

The state Department of Education should use the Tonga incident to improve its communications. Fourteen schools in inundation zones were closed following the quake, but there was some confusion about why others not in hazard areas but close by weren't shut down. The department should make sure parents and school officials are adequately prepared to take action and to know where their children go if evacuation is necessary during school hours.

The quake in Tonga was rare. The last one was in 1919 and generated small waves that did no major damage here. Still, we do need to be prepared.