How you might be warned about a Tsunami
Official Tsunami Watches, Tsunami Warnings, No Threat Bulletins and Tsunami Cancellations and Tsunami Warning Summaries are issued by the Joint Australian Tsunami Warning Centre
Tsunami Warnings will indicate a threat level that indicates whether tsunami are likely to:
- affect the marine and immediate foreshore;
- cause land inundation of low lying coastal areas, or
- pose no threat to an area
About Tsunami Watches, Warnings, No Threat Bulletins, Cancellations and Warning Summaries
No Threat Bulletin:
To advise people that the earthquake has been assessed and that no tsunami threat exists.
In the first stage seismologists determine that there is the potential for an identified undersea earthquake to cause a tsunami threat to Australia. If there is no threat, a National Tsunami No Threat Bulletin will be issued.
To advise people that a tsunami threat may exist and that they should look out for further updates.
In the first stage seismologists determine that there is the potential for an identified undersea earthquake to cause a tsunami threat to Australia. If there is a threat, the Bureau will issue a National Tsunami Watch.
To advise people that a tsunami threat does exist and to advise them of the level of threat and action they should take.
If sea level observations and further data confirm the tsunami threat, or if any potential first point of impact is less than 90 minutes away, the Bureau, on behalf of the JATWC, will use its severe weather communication infrastructure to issue Tsunami Warnings for the States and Territories under threat.
Tsunami Warning Cancellation
When the main threat has passed or if a tsunami didn't eventuate, the Bureau will issue a Tsunami Watch Cancellation or Tsunami Warning Cancellation. The relevant State or Territory emergency authority will inform the public when it is safe to return to the affected area.
National Tsunami Warning Summary
To provide the public, media and emergency authorities with the status of tsunami warnings nationally
About Threat Levels
Tsunami Warnings are broken into 3 different threat levels:
An undersea earthquake has been detected, however it has not generated a tsunami, or the tsunami poses no threat to Australia and its offshore territories.
Marine and Immediate Foreshore Threat
Warning of potentially dangerous rips, waves and strong ocean currents in the marine environment and the possibility of only some localised overflow onto the immediate foreshore.
Land Inundation Threat
Warning for low-lying coastal areas of major land inundation, and flooding, dangerous rips, waves and strong ocean currents in the marine environment.
Sample Tsunami WarningThis image is a sample of the image released by the Joint Australian Tsunami Warning Centre (JATWC) when a Tsunami Warning is issued.
The blue area indicates the areas to be affected by the marine and immediate foreshore threat, while the green area shows the areas that are predicted not to be affected by the tsunami.
Below is a sample of the safety advice that may accompany a Tsunami Warning issued by the Joint Australian Tsunami Warning Centre