A powerful 8.0 magnitude earthquake rocked Japan's northernmost island of Hokkaido early September 25, 2003, killing one person and injuring 388 more. More than 10,000 families were evacuated after the quake struck at 4:50 a.m. Massive power outages resulted from the quake, as did an oil refinery fire and a train derailment. Kushiro Airport was closed after the ceiling of its air traffic control tower collapsed.

This powerful earthquake did not surprise seismologists, since Japan's governmental Earthquake Research Committee announced in March that there was a 60 percent chance of an 8.1 magnitude or greater earthquake striking the coast of the Tokachi region within 30 years. Although tsunami warnings were issued for Japan, Russia, Guam, and other neighboring Pacific islands, luckily, only a single series of the damaging waves were recorded and warnings subsided without additional disruption.

While this recent Japanese earthquake did not generate a tsunami in Hawaii, the threat of a tsunami striking Hawaii after an earthquake in the Pacific Rim is very real. Tsunamis are a concern because more people have died from tsunamis in Hawaii than from any other natural disaster including hurricanes, earthquakes, floods, and volcanic eruptions. Such disasters emphasize the importance of the Pacific Disaster Center's (PDC's) Automated Tsunami Alert System.

PDC created and deployed the Automated Tsunami Alert System in 1999 at the request of Hawaii State Civil Defense.  The Automated Tsunami Alert System provides Hawaii's emergency officials with critical travel-time information for a tsunami that may be generated when a major earthquake occurs.  The system improves emergency officials' awareness of a potential tsunami in three ways: by automatically delivering the official Pacific Tsunami Warning Center tsunami bulletins via pager and cell phone to emergency managers; automatically posting the official tsunami bulletins to PDC's operational-oriented web site; and posting tsunami travel times to Hawaii on the Internet using a PDC modeling capability (Figure 1).

From an emergency management perspective, PDC's Automated Tsunami Alert System provides rapid and uniform notification of tsunami advisory, watch, warning, and cancellation bulletins to more than 30 Hawaii State Civil Defense personnel on a 24/7 basis anywhere within pager or cell phone range. This facilitates rapid emergency management decisions and actions for response purposes.

Such an alert system is crucial because from the time a tsunami develops, to the time it reaches Hawaii's shores, ranges from as little as a few minutes to more than 12 hours, depending on whether it is an offshore landslide or an earthquake across the Pacific, such as the recent one in Japan.

Figure 1. PDC’s Automated Tsunami Alert System requires input tsunami bulletin information from the Pacific Tsunami Warning Center and produces automated tsunami notification alerts to emergency managers’ cell phones, pagers, and email as well as outputs a model run to PDC’s web site displaying estimated tsunami travel times (in hours) across the Pacific Ocean for emergency management purposes.

The tsunami alert generated from a  Hokkaido 8.1 magnitude earthquake on Thursday, September 25, 2003 is a good example of the benefit of PDC's Automated Tsunami Alert System to emergency managers. Although no tsunami reached Hawaii, behind the scenes emergency officials managed information from the Automated Tsunami Alert System. On the morning of the earthquake, some emergency managers in Hawaii were notified of the tsunami potential from the distant earthquake within seconds of the tsunami bulletin being issued by the Pacific Tsunami Warning Center in Honolulu. Upon receiving the automatic alert, emergency officials monitored the situation that could have led to further response and actions, if required, to prepare for the possible event.

Today, within the State of Hawaii, the alert system also broadcasts hurricane, weather, and earthquake bulletins from federal warning centers to emergency staff pagers or cell phones operational in Hawaii. The alert system also provides a foundation for broadcasting additional hazard bulletins in the future, such as flash floods and volcano alerts. PDC is studying ways to enhance this automated alert capability to assist international inquiries interested in similar technology applications.