Daniel Jaksa, Operations Team Leader of the Joint Australian Tsunami Warning Centre (JATWC) gave a presentation at the Geoscience Australia Open day in Canberra Sunday 26 August 2007 entitled "Earthquakes to Evacuate".
Boxing Day Tsunami
Geoscience Australia is part of the Australian and international tsunami warning systems. Daniel played a sound recording of the 26 December 2004 earthquake, from a hydrophone at Diego Garcia, 2,600 kilometers from the epicenter. This was a deep rubling which seemed to go on forever.
The tsunami caused by the earthquake hit Indonesia 15 minutes later. Daniel showed video of the tsunami in Phuket, Thailand, 30 minutes after the first wave. He pointed out that the first wave is not necessarily the largest. The Tsunami stuck Kenya eight hours later. In total 230,000 people were killed and 45,000 missing.
In response the Australian government provided $68.9 M for a four year program to establish a warning system. Involved are GA, Australian Bureau of Meteorology (BoM), Emergency Management Australia (EMA), and the State Emergency Services (SES).
A tsunami with a 9m runup hit Steep Point WA at about 7:30pm. This destroyed a campsite, but the family were able to hold onto their car and avoid being swept out to sea.
Establishing an Australian Tsunami Warning Centre
The Joint Australian Tsunami Warning Centre (JATWC) is jointly run by GA (earthquake detection), and Bureau of Meteorology, (sea level monitoring). The Operations Hub for GA's part of AusTWC was officially opened on 1 December 2006 in Canberra
GA detects earthquakes, evaluates them for tsunamigenic potential, passes the information on to BoM and evaluates the results. The GA person on duty (called the "watch stander") evaluates an earthquake within five to ten minutes of detection. The watch stander presses a red button to issue an electronic alert to BoM. The BoM only have one tsunami buoy currently (others being installed) , plus tide gauges to detect a tsunami. Tsunami propagation models are used to evaluate the size and timing of a potential tsunami.
Daniel showed news reports from North Queensland of evacuations due to an earthquake in the Solomon Islands 2 April 2007 and later beach closures along the east coast of Australia. He showed a simulation of how an earthquake in New Zealand could cause a tsunami inundating Wollogong. This was a chilling demonstration. But the high risk areas in Australia are the North West shelf and around Hobart.
Dangerous Confusion in Australian Tsunami Warning System
The AusTWC computer system at GA is mirrored at the BoM, in case of a failure at GA in Canberra. Also other warning centers around the region can assist if the Australian system is not available. However, the major problem with the Australian system is not the technical design, or competence of the scientific staff, but the lack of effort put into communicating warnings to the public.
Like other regional warning centers, the JATWC does not directly issue public alerts, this is left to state governments via EMA. As a result there is a potential delay and lack of standard terminology in the messages issued. With the most recent Solomon Islands tsunami warning there was a lack of preparedness, particularly by the Queensland government. Resulting delays and confusion could result in a large loss of life in a future tsunami.
There is a lack of standard terminology in the Australian approach to tsunami warning. As an example the BoM refer to the Australian Tsunami Warning System (ATWS), Australian Tsunami Alert System (ATAS), and the Joint Australian Tsunami Warning Centre (JATWC). GA refer to the Australian Tsunami Warning Centre but use a different acronym for it to BoM: AusTWC. Research by one of my students at ANU has shown that in an emergency the credibility of emergency information, is very important in the public accepting and acting on the information. If there are different names for the same organization, this will cause dangerous confusion.
The Australian Government has recently decided to intervene in state matters in several areas. Providing tsunami warnings direct to the public is one areas in which such intervention would be justified. The "last century" approach of GA passing a tsunami warning to EMA who pass it to SESs who then decide to pass it on (depending on the whim of the state premier) is not satisfactory. Instead each party should pool the information, interpretation and advice they have available. All those involved, including the general public, can then make an informed decision as to what to do.
During the 2004 Tsunami, the staff of the Pacific Tsunami Warning Centre attempted to warn the Indian Ocean region, but there was no system or procedure by which to do so. These staff could be forgiven for this unanticipated failing. However, this does not apply to the staff of the Joint Australian Tsunami Warning Centre. The scientists and public servants involved in the centre have an obligation to ensure that they can issue clear warnings to the Australian public. The excuse that it is someone else's job to pass on the warnings is not acceptable.
Problems with Indian Ocean Tsunami Warning System
In addition to administrative problems with the system in Australia, there are also problems with the electronic format of messages used for tsunami warnings in the region. The result of this could be that even when a timely message is issued, it may not be received or understood. AusTWC and similar organizations need to work together on better formats for the information.
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