Topic: Tsunami Warning

[Kristy Norman]

I have just noticed the cancelled Tsunami warning on BOM. Can someone fill me in?

[Richary]

Earthquake off the bottom of New Caledonia yesterday. I saw this warning being cancelled, and also there was another one on the 15th with an earthquake in the same area.

From the TVNZ news site:

A strong earthquake of 6.6 magnitude struck 323 km (201 miles) east southeast of Tadine, Loyalty Islands, in New Caledonia, the US Geological Survey said on Monday. The quake was 33 km (20.5 miles) deep.

Interestingly it says no tsunami warning was issued, maybe not for NZ/NCL but it obviously was for here.

Have only seen the cancellations though, not the initial warning itself. Would like to see the text.

[Colin Maitland]

there has been 2 tsunami warnings this week. I constantly watch the earthquakes around the world.

Warning 1

Earthquake Details
Magnitude   6.7
Date-Time   

    * Sunday, January 18, 2009 at 14:11:45 UTC
    * Monday, January 19, 2009 at 02:11:45 AM at epicenter
    * Time of Earthquake in other Time Zones

Location   30.108°S, 178.000°W
Depth   10 km (6.2 miles) set by location program
Region   KERMADEC ISLANDS, NEW ZEALAND
Distances   95 km (60 miles) S of Raoul Island, Kermadec Islands
170 km (105 miles) NNE of L'Esperance Rock, Kermadec Islands
1005 km (620 miles) NE of Auckland, New Zealand
1395 km (870 miles) NNE of WELLINGTON, New Zealand
Location Uncertainty   horizontal +/- 5.9 km (3.7 miles); depth fixed by location program
Parameters   NST=257, Nph=257, Dmin=95.3 km, Rmss=0.91 sec, Gp= 22°,
M-type=regional moment magnitude (Mw), Version=R
Source   

    * USGS NEIC (WDCS-D)

Event ID   us2009bzaw 
Magnitude   6.8
Date-Time   

The warning you have asked about.

    * Monday, January 19, 2009 at 03:35:19 UTC
    * Monday, January 19, 2009 at 02:35:19 PM at epicenter
    * Time of Earthquake in other Time Zones

Location   22.604°S, 170.881°E
Depth   10 km (6.2 miles) set by location program
Region   SOUTHEAST OF THE LOYALTY ISLANDS
Distances   120 km (75 miles) W of Ile Hunter, Loyalty Isl., New Caledonia
330 km (205 miles) ESE of Tadine, Loyalty Islands, New Caledonia
455 km (285 miles) E of NOUMEA, New Caledonia
1620 km (1010 miles) NNW of Auckland, New Zealand
Location Uncertainty   horizontal +/- 7.2 km (4.5 miles); depth fixed by location program
Parameters   NST= 99, Nph= 99, Dmin=>999 km, Rmss=1.21 sec, Gp= 22°,
M-type=regional moment magnitude (Mw), Version=8
Source   

    * USGS NEIC (WDCS-D)

Event ID   us2009caak

The biggest in our region this year was

03/01/2009    19:43:49    -.51    132.86    0    7.7      West Irian Region, New Guinea

to view what is happening go to

http://www.ga.gov.au/bin/listQuakes ( Australian region,a closer view of what happening here. )  or

http://earthquake.usgs.gov/eqcenter/recenteqsww/  ( this is the better site of the 2)

you will get a shock when you see how many QUAKES a day/week happen.  The most I have seen in a 7 day period on the USGS is 445 quakes.

[Kristy Norman]

Thanks guys. Wow! I had no idea earthquakes were so common. That's really scary!

[Colin Maitland]

just adding to the Tsunami Warning,

Like Richary said, "I have only seen the cancellation of the warning, "

I  have only seen the cancellation of warning as well, never the full warning, which is a good thing, but below is the explanation,  of  why we may only receive those, ( it may also be that the warning will  only be in place for 15 min, as an example, and we have missed it, I am trying to research that ? more due to the recent increase of earthquakes around Papua New Guinea/ Indonesia region.)

it states from:
Tsunami Watches and Warnings for Australia

The Joint Australian Tsunami Warning Centre (JATWC), jointly operated 24 hours a day by the Bureau and GA detects, monitors, verifies and warns of any tsunami threat to the coastline of Australia and its offshore territories.

The first stage of the tsunami warning process is a 'tsunami watch' phase, where seismologists have determined that there is the potential for an identified undersea earthquake to cause a tsunami threat to Australia. If there is a threat, the Bureau would issue a National Tsunami Watch. If there is no threat, a National Tsunami No Threat Bulletin would be issued. The National Tsunami Watch may be reissued if a tsunami remains unconfirmed by sea level observations and any potential first point of impact on Australia is more than 90 minutes away (the minimum time criteria for warning).

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. The Bureau's Regional Forecasting Centres (RFCs) in capital cities are the main liaison point for Emergency Services during tsunami events.

Once separate tsunami watches or warnings are being issued for individual States and Territories, a National Tsunami Warning Summary will also be issued listing all the watches, warnings and cancellations that are in effect for the current tsunami event. The JATWC website www.bom.gov.au will provide a complementary coastal threat graphic showing the regions currently under threat. (see previous pages)
Cancellation of a Tsunami Warning


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. A National Tsunami Event Summary is then issued after the event.

There must be some legality or issuing only the cancellation of a warning. or it may be to reassure us that they are on the ball and were aware of the situation,and that they have systems in place.

 ( full details of the system  can be found at http://www.bom.gov.au/tsunami/about_tsunami_warnings.shtml & http://www.bom.gov.au/tsunami/about_jatwc.shtml)

[Michael Bath]

None of the new products made it onto the regular email or SMS distribution of warnings that I'm subscribed to so there needs to be some work there if they want them properly distributed.