Published on October 22, 2007
Tsunami Warning and Tsunami Hazard Mitigation Efforts in Nicaragua: Tsunami Warning and Tsunami Hazard Mitigation Efforts in Nicaragua Wilfried Strauch, INETER, Managua http://www.ineter.gob.ni/geofisica/tsunami/tsunami.html Tsunami causes Tsunami hazard estimation Warning system Tsunami en los 1990: Tsunami en los 1990 Nicaragua 1992: Nicaragua 1992 Tsunami earthquakeMw=7.6 Very low seismic effect No warning > 170 killed 1992: 1992 No knowledge about tsunami hazard No seismic network No communications system No tsunami warning system No trained personnel No educated population Actions of INETER after 1992: Actions of INETER after 1992 Sept. 1992: of seismic monitoring, service 24x7 1993: Integration into PTWS, ITSU Development seismic network (1992:2 estaciones, 2005: 61 estaciones) Development of Monitoring and Early Warning center Development Information&Communications del Systems Execution of projects on tsunami hazard Development of sea gauge network Pushing a Regional Warning System in CA 2005 Seismic broad band network, Small seismic array, 2005 Facilities for immediate information to population Tsunami sources in Nicaragua: Tsunami sources in Nicaragua Tsunami Catalogue: Tsunami Catalogue 1500-2002 – 49 tsunamis in Central America 5 affected Nicaragua 1 desastrous en Nicaragua (1992) Sources: Morales, 1992-2005; Molina, 1994, Fernández et al, 1999 Funding: Funding After 1992 tsunami little interest of funding agencies (“low probability for another tsunami”) Participation of INETER in research projects Additional funding by Nicaraguan goverment – financial source for development of seismic monitoring and Tsunami warning system Basic research on Tectonics, structure, etc: Basic research on Tectonics, structure, etc After the 1992 tsunami – deeper earthquake and tsunami knowledge for Nicaragua and CA due to a large number of research work and projects on subduction processes, tectonics, geology, volcanology, seismic source mechanisms, tsunami generation, .. Especially: NSF funded “Subduction factory” DFG/Germany funded “Special research area” E.g. 2005 – temporary broad band network for crustal structure and seismicity studies. Nicaragua & Costa Rica. 46 stations . With Boston Univ. & Brown Univ. Tsunami due to submarine landslide: Tsunami due to submarine landslide Shaded relief map of multibeam bathymetry data showing the Jaco scarp produced by seamount subduction offshore Costa Rica. A faulted block occurs downslope of the main scarp, which seems to indicate that detached blocks creep along headwall faults without loosing their coherent structure. However, a slumped mass at the base of the headwall scarp indicates that blocks may eventually fail catastrophically. Ranero & Weinrebe, 2004 Source: GEOMAR, 2004 Lake Managua: Tsunamis caused by volcanic explosion: Lake Managua: Tsunamis caused by volcanic explosion Sources: Volcanic hazards in Nicaragua: Past, present, and future. A.Freundt, St.Kutterolf, H.-U.Schmincke, T.Hansteen, H.Wehrmann,W. Perez,, W. Strauch, Navarro, in preparación Tsunami in Lake Managua, Nicaragua, triggered by a compositionally zoned plinian eruption, A. Freundt, St. Kutterolf, H. Wehrmann, H-U. Schmincke, W.Strauch,Conference, IAVCEI, Chile, 2004 Max. Height of waves : 20 m When? Aprox 2000 years ago Foto: Section of Mateare in the low area Oeste de la West of Chiltepe peninsula. Unit A A, fallout, product of discontinuous plinian activity 2)Mateare sand (MS) deposited by the tsunami,and 3) Unit B – massive fallout of pommes of the stable plinian phase of the eruption.. Lake Nicaragua: Tsunami by volcano collapse ?: Lake Nicaragua: Tsunami by volcano collapse ? Mombacho volcano: Prehistorical collapse. No evidences yet for ocurrence of tsunami. Other possible sites: Momotombo volcano Concepción volcano. In process: Study on possible tsunami generation and propagation in Lake Nicaragua. Source: INETER-NGI-Project Tsunami hazard estimation: Tsunami hazard estimation Identification of high risk areas, “hot spots”: Identification of high risk areas, “hot spots” Height -> “Hazard” 10 - 20 m low 5 - 10 m high < 5 m very high Source:Strauch, 2005 Corinto: Corinto “Hot spot” Corinto Population: Aprox. 10,000 Height: 4 msnm. Evacuation route 10-15 km !??? Save place Inundation maps based on numerical simulation, Pacific coast(to be finished December 2005): Inundation maps based on numerical simulation, Pacific coast (to be finished December 2005) Recollection of existing bathymetric data Bathymetric mapping of Masachapa area Digital elevation model of the coastal strip Seismic source mechanism, 1992 tsunami earthquake Numerical simulation of tsunami generation and propagation (TIME) Inundation maps Source: INETER-JICA-Project Slide17: Corinto San Juan del Sur Puerto Sandino Study areas – most populated places Masachapa Bathymetry Source: INETER-JICA-Project, 2004-06 Pilot Project: Tsunami disaster prevention in Masachapa area: Pilot Project: Tsunami disaster prevention in Masachapa area Source: INETER-COSUDE Project, 2005-06 Information and education Local hazard map; Save places, evacuation routes Tsunami signs Prevention measures for schools Installation of sirens Participation of local administration and population Alert System: Alert System Alert system: Local tsunami: Alert system: Local tsunami Magnitud: > 7.0 Location: Nicaraguan Pacific Ocean Local Tsunami – Alert System: Local Tsunami – Alert System * Earthquake->Tsunami Seismic recording Civil Defense – to local administrations, 10 min Evacuation wave arrives in 45 minutes! Analysis – Seismic data center Automatic procedures: -Broad band sensor Small seismic array Virtual regional network Radio, TV stations – to population, 2 min Cellular phone –to local population, 2 min 10 min ? human factor 3 min Civil Defense Communications System: Chinandega (El viejo) 1.- Venecia 2.- Aposentillo 3.- Jiquilillo 4.- Aserraderos 5.- Los Zorros 6.- Padre Ramos 7.- Mechapa 8.- Punta Nata 9.- Potosí Chinandega (Corinto) 10.- Corinto 11.- Isla del Cardón 12.- Isla del Amor Chinandega (El Realejo) 13.- Isla Maderas Negras 14.- Isla Paredones 15.- Paso Caballos León 16.- El Tránsito 17.- Puerto Sandino 18.- Salinas Grandes 19.- Poneloya 20.- Las Peñitas 21.- Los Brasiles Managua 22.- Salamina 23.- Montelimar 24.- Masachapa 25.- Pochomil 26.- San Diego 27.- Gran Pacífica 28.- Miraflores Carazo 29.- Casares 30.- La Boquita 31.- Bocana de Masapa Jinotepe 32.- Tipilapa 33.- Huehuete 34.- La Bocana Rivas 35.- El Ostional 36.- San Juan del Sur 37.- El Menco 38.- El Gigante 39.- San Martín 40.- Las Salinas 41.- El Astillero 42.- La Flor (130,000) under risk 1 34 38 37 2 3 4 6 5 8 7 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 35 36 39 40 41 42 Civil Defense Communications System Source Defensa Civil, 2005 New communication methods(in development): Alert messenger to PC screen of radio/TV presenters (under testing) SMS cell phone to decision maker (under testing) SMS cell phone to large sectors of population (under development) New communication methods (in development) Thank you !: Thank you ! Towards a Regional Tsunami Warning System in Central America: Towards a Regional Tsunami Warning System in Central America Wilfried Strauch, INETER, Managua with support from: CEPREDENAC INSIVUMEH – Guatemala; SNET- El Salvador; OVSICORI, UCR, CASC-Costa Rica; UPA- Panama; COPECO-Honduras. “Hot Spots” Tsunami CA: “Hot Spots” Tsunami CA Corinto Panamá Puerto Armuelles Puntarenas El Triunfo Boca del Toro Bilwi El Bluff/Bluefields San Carlos - Low profile of the coast; -high population concentration Hight -> “Hazard” 10 - 20 m low 5 - 10 m high < 5 m very high Colón Regional program for a tsunami warning system in Central America: Regional program for a tsunami warning system in Central America Proposal of INETER (2003) to CEPREDENAC, based on experience in Nicaragua Adopted in 2005 Creation of national warning systems Every national WS obtains data from all other countries, in real time Every national WS transmits its warning messages to all other countries A variety of technical communications measures are tobe used A very redundant system The 2004 Tsunami in South Asia stimulated:: The 2004 Tsunami in South Asia stimulated: Actions of CEPREDENAC (Regional Center for Disaster Prevention) Tsunami hazard studies and education measures in Costa Rica Interest of Emergency Commissions in all CA countries Meetings of the relevant institutions of all CA countries More interest of funding agencies Activities in CA towards a Tsunami Warning System, 2005: Activities in CA towards a Tsunami Warning System, 2005 Meeting of body of Directors of CEPREDENAC,Kobe, Decision about a strategic meeting Strategic meeting on Tsunami WS, in San Salvador, Decision on program Regional Tsunami WS - Tsunami Workshop, 25-27Abril, Managua Presentation of immediate actions and project profiles - Workshop on digital seismic data acquisition and processing Training for data seismic data exchange and virtual networks National Warning Centers: National Warning Centers Consider the threat of local tsunamis: The local tsunami threat is more efficient using the national capacities of seismic and hidrografic monitoring and using local communications methods to the population. Independent alert for regional eventss : For the detection of a potentional regional threat a single seismic station can be sufficient (e.g. with TREMORS software). Interpretation of the messages of PTWC : It is national responsability to interprete the inforemation or warning messages of PTWC and to decide how to act on them. Dissemination of alert messages: Only the national centers can cooperate efficiently with national and local authorities to make sure that the warning messages are distribute rapidly to the areas under risk and to establish evacuation plans. Immediate actions, planned for 2005: Alert system - Formation of a technical steering committee - Formation of National Warning Centers - Integration in PTWS of all CA countries (missing: Panama, Honduras) - Elaboration of national communications plans, preliminary Monitoring and communications network - Exchange of seismic data in real time, virtual seismic networks Projects - Elaboration of project proposals for long an medium term development Immediate actions, planned for 2005 Possibles Projects: Possibles Projects Monitoreo y Alerta .Improvement/installation of a seismic broad band network, satelital . Installation of a sea gauges, including off shore . Information on alternative tsunami detection methods Hazard mapping . Hazard mapping, tsunami simulation, inundation maps . “Hot spot” = population centers under high risk . Factibility studies on special protection measures for “Hot Spots” . Studies of tsunami causes – earthquakes, volc.explosiones, submarine slides Información y Educación . Alternative measures for information and education of population Muchas Gracias!: Muchas Gracias!