Tsunami warning technology in Australia

The Australian Tsunami Admonishing Arrangement (ATWS) is a civic accomplishment involving the Australian Bureau of Meteorology (Bureau), Geoscience Australia (GA) and Emergency Management Australia (EMA) to accommodate a absolute tsunami admonishing arrangement able of carrying appropriate and able tsunami warnings to the Australian citizenry by 2009. The activity additionally supports all-embracing efforts to authorize an Indian Ocean tsunami admonishing system, and contributes to the abetment of tsunami warnings for the South West Pacific.

'Tsunami' is a Japanese word, which translates as 'harbour wave', now acclimated internationally to accredit to a alternation of after-effects travelling beyond the ocean with acutely continued wavelengths (up to hundreds of kilometres amid beachcomber crests in the abysmal ocean). Tsunami are usually the aftereffect of a abrupt acceleration or abatement of a area of the earth's band beneath or abreast the ocean. A seismic agitation can displace the baptize column, creating a acceleration or abatement in the akin of the ocean above. This acceleration or abatement in sea akin is the antecedent actuation breeding a tsunami wave.

On 26 December 2004 the fourth better convulsion to be recorded back 1900, with a Moment consequence (Mw) of 9.2, occurred off the west bank of Northern Sumatra in Indonesia. It led to one of the better losses of activity from a accustomed abnormality to be recorded in avant-garde times. A tsunami generated from the displacement of the sea attic of up to 10 m over a breadth of 1200 km hit the bank of 11 countries in and about the Indian Ocean, demography the lives of added than 280,000 people.

Subduction zone along tectonic plate boundaries around Australia

Subduction zone along tectonic plate boundaries (shown in red) around Australia that have the potential to generate a tsunami that may impact on Australia's coast (source: Geoscience Australia).

Australia's vulnerability to tsunami

Australia is belted on the northwest, northeast and east by some 8,000 km of alive tectonic bowl abuttals able of breeding tsunami, which could ability our bank aural two to four hours. One-third of all earthquakes common action forth these boundaries. The appulse of a tsunami hitting accessible below areas of the Australian bank could be significant.

As a absolute aftereffect of the tsunami generated off the bank of Indonesia on 26 December 2004, the Australian Government articular the charge to be able to acquaint the Australian citizenry of such phenomena, with the aim of minimising the accident of activity and the bread-and-butter appulse on its population. At that time an breezy Australian Tsunami Alert Arrangement (ATAS) was operated accordingly by the Bureau, GA and EMA. The ATAS arrangement had bound capabilities in tsunami ecology and warning.

Enhancing Australia's capabilities

The Australian Government has committed $68.9M over four years to authorize an Australian Tsunami Admonishing Arrangement by 2009. This includes: Establishment of the Joint Australian Tsunami Admonishing Centre (JATWC) with 24/7 ecology and assay accommodation for Australia; The advancement and amplification of sea-level and seismic ecology networks about Australia and in the Indian and South West Pacific Oceans;

Implementation of civic apprenticeship and training programmes about tsunami;Assistance to the Intergovernmental Oceanographic Commission (IOC) in developing the absolute Pacific Tsunami Admonishing & Mitigation Arrangement (PTWS) and establishing an Indian Ocean Tsunami Admonishing & Mitigation Arrangement (IOTWS); and

Technical abetment to advice body the accommodation of scientists, technicians, and emergency managers in South-West Pacific and Indian Ocean countries.

How does the new system work?

GA operates an enhanced network of seismic stations nationally and has access to data from international monitoring networks. It advises the Bureau of the magnitude, location and characteristics of a seismic event which has the potential to generate a tsunami.

Based on this seismic information from GA, as well as advisories from the Pacific Tsunami Warning Centre (PTWC) in Hawaii and from neighbouring countries with tsunami detection capacity, the Bureau runs a tsunami model to generate a first estimate of the tsunami size, arrival time and potential impact locations. The Bureau verifies the existence of a tsunami using information from an enhanced sea level monitoring network.

The Bureau then promulgates advice and warnings on any possible tsunami threat to State & Territory emergency management services, media and the public.

EMA liaises with the operations centres of affected State and Territory emergency management organisations and coordinates Federal assistance as required.

EMA also has responsibility for improving public awareness and preparedness for tsunami in Australia.