Vigilance Tsunami 11 Avril 2012 - M8.6 Indonésie

11 Avril 2012 @ 1600utc - Fin du Vigilance tsunami mais la mer restera temporairement forte dans l'Océan Indien, suite au seisme en Indonésie

Termination of Tsunami Watch issued at 20:30 hrs on 11 April 2012

Observations indicate that waves expected were very small and not significant at Rodrigues, St. Brandon, Agalega and Mauritius.Furthermore, International Tsunami Warning Centres are not predicting damaging waves hitting the islands of the Republic of Mauritius.Therefore the Tsunami watch is being terminated.

However, the public is advised to be careful on beaches and in lagoon as there are fluctuations in the sea level and abnormal rapid currents are still likely tonight.

End=

Les observations des marégraphes du IOC des îles dans la République de Maurice ont enregistrés une anomalie entre 30-60cm ce qui justifie la fin du suivi tsunami chez nous.

Plus de peur que de mal!

Mais c'est pas fini, la région indonésienne restera toujours sous haute surveillance par les RTSP (regional tsunami service provider qui sont L'inde, indonésie et Australie pour l'Océan Indien) pour les jours avenir ...

A bientôt

11 Avril 2012 @ 1600utc - Vigilance mer forte dans l'Océan Indien, suite au seisme en Indonésie

 

En ce moment les agitations sont enregistrées à Port-Louis:



 

 (data credit: IOC)

Les observations en temps réel avec les marégraphes du IOC montrent clairement que le seisme en Indonésie a provoqué une agitation sur la surface de la mer à travers l'Océan Indien depuis l'épicentre du seisme. Le marégraphe à Rodrigues l'indique aussi et comme prévu par MMS dans ses bulletins, c'est bien aux alentours de 1800hrs (1400utc) que l'île a commençé d'enregistrer ces agitations comme on peut le constater sur les observation du marégraphe à l'île Rodrigues à travers IOC. Pour le moment, calme plat à Agalega/St-Brandon et meme à Maurice.

Dans le bull No2 de MMS:
"The waves generated are expected to reach Rodrigues and St Brandon at around 1745 hours today and there may be fluctuations, rise in the sea level and rapid currents at Rodrigues and St Brandon. The same are expected around 1900 hours at Mauritius and Agalega."

Mais heureusement, selon les donnés des autorités de l'Indonésie et meme en Inde à travers SKYNEWS indiquent qu'il n'y a pas eu grand dégats comme en 2004.

Voici des liens concernant le seisme en image de l'Indonésie:

-RT

-HeraldSun

11 Avril 2012 @ 1300utc - Vigilance tsunami dans l'Océan Indien

Tsunami warning bulletin de MMS

Tsunami Watch  Bulletin Number 2 issued at 1700 hours on 11 April 2012The earthquake which occured this afternoon off the West coast of SUMATRA is still being monitored by International Tsunami Warning Centres. So far there has been evidence of small tsunami wave.

The  public at Rodrigues, Agalega, St Brandon and Mauritius are requested to stay away from beaches and lagoons. Boats must be secured.

The waves generated are expected to reach Rodrigues and St Brandon at around 1745 hours today and there may be fluctuations, rise in the sea level and rapid currents at Rodrigues and St Brandon. The same are expected around 1900 hours at Mauritius and Agalega.

The public is advised to take all precautions and stay away from beaches.

End=

 

 

Bulletin No 4 du PTWC:

MEASUREMENTS OR REPORTS OF TSUNAMI WAVE ACTIVITY

 GAUGE LOCATION        LAT   LON    TIME        AMPL         PER
 -------------------  ----- ------  -----  ---------------  -----
 TELUKDALAM ID         0.6N  97.8E  0952Z   0.15M /  0.5FT  08MIN
 SABANG ID             5.8N  95.3E  1010Z   0.36M /  1.2FT  06MIN
 MEULABOH ID           4.1N  96.1E  1007Z   1.06M /  3.5FT  12MIN
 DART 23401            8.9N  88.5E  0956Z   0.03M /  0.1FT  06MIN
 SABANG ID             5.8N  95.3E  0956Z   0.31M /  1.0FT  08MIN

 LAT  - LATITUDE (N-NORTH, S-SOUTH)
 LON  - LONGITUDE (E-EAST, W-WEST)
 TIME - TIME OF THE MEASUREMENT (Z IS UTC IS GREENWICH TIME)
 AMPL - TSUNAMI AMPLITUDE MEASURED RELATIVE TO NORMAL SEA LEVEL.
        IT IS ...NOT... CREST-TO-TROUGH WAVE HEIGHT.
        VALUES ARE GIVEN IN BOTH METERS(M) AND FEET(FT).
 PER  - PERIOD OF TIME IN MINUTES(MIN) FROM ONE WAVE TO THE NEXT.

 NOTE - DART MEASUREMENTS ARE FROM THE DEEP OCEAN AND THEY
        ARE GENERALLY MUCH SMALLER THAN WOULD BE COASTAL
         MEASUREMENTS AT SIMILAR LOCATIONS.

 EVALUATION

 SEA LEVEL READINGS INDICATE A TSUNAMI WAS GENERATED. IT MAY
 ALREADY HAVE BEEN DESTRUCTIVE ALONG SOME COASTS.

 BASED ON THESE DATA THE THREAT CONTINUES FOR ALL COASTAL AREAS OF
 THE INDIAN OCEAN. FOR THOSE AREAS - WHEN NO MAJOR WAVES HAVE
 OCCURRED FOR AT LEAST TWO HOURS AFTER THE ESTIMATED ARRIVAL TIME
 OR DAMAGING WAVES HAVE NOT OCCURRED FOR AT LEAST TWO HOURS THEN
 LOCAL AUTHORITIES CAN ASSUME THE THREAT IS PASSED. DANGER TO
 BOATS AND COASTAL STRUCTURES CAN CONTINUE FOR SEVERAL HOURS DUE
 TO RAPID CURRENTS.  AS LOCAL CONDITIONS CAN CAUSE A WIDE
 VARIATION IN TSUNAMI WAVE ACTION THE ALL CLEAR DETERMINATION MUST
 BE MADE BY LOCAL AUTHORITIES.

11 Avril 2012 @ 1000utc - Vigilance tsunami dans l'Océan Indien

Un seisme de M8.6 [USGS] vient de sécouer la côte Indonesienne à environ 22km en profondeur.

Ce seisme vient de declencher un tsunami dans l'Océan Indien, les "tides-gauges" [1]Telukdalam, [2]Sabang, [3]Meulaboh sur la côte de l'indonesie à quelques kilomètres de l'épicentre du seisme indiquent qu'un tsunami a été généré suite à ce seisme.

Selon une simulation provisoire, le tsunami pourra atteindre les côtes des îles des mascareignes dans moins de 6hrs (c'est à dire aux alentours de 18hrs LT, depuis que le seisme a été enregistré) .

 

 

 (images credit: NOAA)

A noter que le seisme du 26 Dec 2004 n'était pas trop loin avec M9.1 à une profondeur de 30km [USGS].

Precautions à prendre:

• Restez bien loin de la plage en début de soirée.

• Ecoutez l'évolution de la situation sur la radio.

Suivez l'évolution du tsunami avec ces liens:

-Tsunami.gov

-Pacific Tsunami Warning Centre, PTWC

-IOC, sea level monitoring


source: PTWC

MEASUREMENTS OR REPORTS OF TSUNAMI WAVE ACTIVITY

GAUGE LOCATION LAT LON TIME AMPL PER
------------------- ----- ------ ----- --------------- -----
DART 23401 8.9N 88.5E 0956Z 0.03M / 0.1FT 06MIN
MEULABOH ID 4.1N 96.1E 0950Z 0.27M / 0.9FT 14MIN
SABANG ID 5.8N 95.3E 0956Z 0.31M / 1.0FT 08MIN

LAT - LATITUDE (N-NORTH, S-SOUTH)
LON - LONGITUDE (E-EAST, W-WEST)
TIME - TIME OF THE MEASUREMENT (Z IS UTC IS GREENWICH TIME)
AMPL - TSUNAMI AMPLITUDE MEASURED RELATIVE TO NORMAL SEA LEVEL.
IT IS ...NOT... CREST-TO-TROUGH WAVE HEIGHT.
VALUES ARE GIVEN IN BOTH METERS(M) AND FEET(FT).
PER - PERIOD OF TIME IN MINUTES(MIN) FROM ONE WAVE TO THE NEXT.

NOTE - DART MEASUREMENTS ARE FROM THE DEEP OCEAN AND THEY
ARE GENERALLY MUCH SMALLER THAN WOULD BE COASTAL
MEASUREMENTS AT SIMILAR LOCATIONS.

EVALUATION

SEA LEVEL READINGS INDICATE A TSUNAMI WAS GENERATED. 

IT MAY ALREADY HAVE BEEN DESTRUCTIVE ALONG SOME COASTS.

BASED ON THESE DATA THE THREAT CONTINUES FOR ALL COASTAL AREAS OF
THE INDIAN OCEAN. FOR THOSE AREAS - WHEN NO MAJOR WAVES HAVE
OCCURRED FOR AT LEAST TWO HOURS AFTER THE ESTIMATED ARRIVAL TIME
OR DAMAGING WAVES HAVE NOT OCCURRED FOR AT LEAST TWO HOURS THEN
LOCAL AUTHORITIES CAN ASSUME THE THREAT IS PASSED. DANGER TO
BOATS AND COASTAL STRUCTURES CAN CONTINUE FOR SEVERAL HOURS DUE
TO RAPID CURRENTS. AS LOCAL CONDITIONS CAN CAUSE A WIDE
VARIATION IN TSUNAMI WAVE ACTION THE ALL CLEAR DETERMINATION MUST
BE MADE BY LOCAL AUTHORITIES.

ESTIMATED INITIAL TSUNAMI WAVE ARRIVAL TIMES AT FORECAST POINTS
WITHIN THE WARNING AND WATCH AREAS ARE GIVEN BELOW. ACTUAL
ARRIVAL TIMES MAY DIFFER AND THE INITIAL WAVE MAY NOT BE THE
LARGEST. A TSUNAMI IS A SERIES OF WAVES AND THE TIME BETWEEN
SUCCESSIVE WAVES CAN BE FIVE MINUTES TO ONE HOUR.

MAURITIUS PORT_LOUIS 20.0S 57.3E 1500Z 11 APR
REUNION ST_DENIS 20.8S 55.2E 1514Z 11 APR