[J04-P] Poster

[J04-P-06] Sea level observations in the coasts of the Mexican Pacific of the tsunami caused by the 2011 Tohoku Earthquake

^○Octavio Gomez-Ramos¹, Jorge Zavala-Hidalgo², Angel Ruiz-Angulo², Felipe Hernandez-Maguey¹, Miriam Zarza-Alvarado¹, Jose Santiago-Santiago¹, Valente Gutierrez-Quijada¹ (1.Geophysics Institute, National Autonomous University of Mexico, 2.Center for Atmospheric Sciences, National Autonomous University of Mexico)

The 2011 Tohoku earthquake (Mw 9.0) generated a powerful tsunami that traveled across the Pacific Ocean, reaching the western pacific on the American coastlines several hours after the initial shock. This event was registered in the 9 tide gauge stations that the Servicio Mareografico Nacional (Instituto de Geofisica, UNAM) had operating at the moment in the coasts of the Mexican Pacific: La Paz, Acapulco, Mazatlan, Huatulco, Puerto Vallarta, Salina Cruz, Lazaro Cardenas, Puerto Madero and Zihuatanejo. The data show that the first station to register the event was Puerto Vallarta at 19:10 UTC, 13 hours and 24 minutes after the earthquake, and the last station to register the perturbation was Puerto Chiapas at 22:06 UTC, 2 hours and 56 minutes later. The highest registered peak range was 3.22 meters in the station of Zihuatanejo, with a dominant period of the oscillations between 17 and 21 minutes, and a height above the tidal forecast of 1.38 meters. The data also show that in Acapulco the highest peak range was not reached during the first wave, it happened three and a half hours later, similar to what has happened with other remote tsunamis such as that generated by the 2014 Iquique earthquake. Thus, far-field tsunamis represent a hazard to our Mexican towns along the coastlines. The observations also suggest that some locations are prone to amplify the waves and could be initially neglected by small resolution forecast resulting from numerical simulations. Therefore, implementing regional forecast systems for remote tsunami events are suggested to alert and act on time against those remote events.