A Probabilistic Tsunami Hazard Assessment for Western Australia

142

Abstract. Extreme natural events, like e.g. tsunamis or earthquakes, regularly lead to catastrophes with dramatic consequences. In recent years natural disasters caused hundreds of thousands of deaths, destruction of infrastructure, disruption of economic activity and loss of billions of dollars worth of property and thus revealed considerable deficits hindering their effective management: Needs for stakeholders, decision-makers as well as for persons concerned include systematic risk identification and evaluation, a way to assess countermeasures, awareness raising and decision support systems to be employed before, during and after crisis situations. The overall goal of this study focuses on interdisciplinary integration of various scientific disciplines to contribute to a tsunami early warning information system. In comparison to most studies our focus is on high-end geometric and thematic analysis to meet the requirements of smallscale, heterogeneous and complex coastal urban systems. Data, methods and results from engineering, remote sensing and social sciences are interlinked and provide comprehensive information for disaster risk assessment, management and reduction. In detail, we combine inundation modeling, urban morphology analysis, population assessment, socioCorrespondence to: H. Taubenböck (hannes.taubenboeck@dlr.de) economic analysis of the population and evacuation modeling. The interdisciplinary results eventually lead to recommendations for mitigation strategies in the fields of spatial planning or coping capacity.

Section: Or the Germanmentioning

confidence: 99%

"Last-Mile" preparation for a potential disaster – Interdisciplinary approach towards tsunami early warning and an evacuation information system for the coastal city of Padang, Indonesia

Taubenböck

Goseberg

Setiadi

et al. 2009

142

“…Probabilistic tsunami hazard assessments (PTHAs) have been created for the United States (Geist and Parsons, 2006;González et al, 2009), Australia (Burbidge et al, 2008(Burbidge et al, , 2009), New Zealand (Power et al, 2007;Power, 2013), the Mediterranean (Sørensen et al, 2012;Lorito et al, 2015), the northwest Indian Ocean (Heidarzadeh and Kijko, 2011), Indonesia (Horspool et al, 2014) and the even the entire globe (Løvholt et al, 2014). At the same time, hundreds to thousands of simulated scenarios of tsunami propagation have been created to inform real-time tsunami forecasting and alerts (e.g.…”

Section: Introductionmentioning

confidence: 99%

The effect of uncertainty in earthquake fault parameters on the maximum wave height from a tsunami propagation model

Burbidge

Mueller

Kaneko

2015

Abstract. Over the last decade precomputed tsunami propagation model databases have been used extensively for both tsunami forecasting and hazard and risk assessment. However, the effect of uncertainty in the earthquake source parameters on the results of the simulated scenarios of tsunami propagation has not always been examined in great detail. Here we have undertaken a systematic study of the uncertainty in the maximum wave height of a tsunami (h max ) as a function of the uncertainty in the rupture parameters of the earthquake that generates it (specifically the strike, dip, rake, depth and magnitude). We have shown that even for the simple case of a tsunami propagating over flat bathymetry, the coefficient of variation (CoV) and skewness of the distribution of h max was a complex function of the choice of rupture parameter, distance and azimuth. The relationships between these parameters and CoV became even more complex as the bathymetry used became more realistic. This has major potential implications for both how warning centres operate in the future and how the uncertainty in parameters describing the source should be incorporated into future probabilistic tsunami hazard assessments.

“…Tsunami hazard assessment can be approached by both probabilistic (PTHA, Probabilistic Tsunami Hazard Assessment) and deterministic methods. When PTHA is performed, it is often considered as an extension of probabilistic seismic hazard assessment (PSHA) (Annaka et al, 2007;Burbidge et al, 2008;González et al, 2009;Grezio et al, 2010;Sørensen et al, 2012;Power et al, 2012), obtaining seismic return periods for potential tsunamigenic earthquakes and incorporating the aleatory uncertainties on the fault and tidal level parameters.…”

Section: Introductionmentioning

confidence: 99%

Tsunami hazard assessment in El Salvador, Central America, from seismic sources through flooding numerical models.

Álvarez‐Gómez

Aniel-Quiroga

Gutiérrez

et al. 2013

Abstract. El Salvador is the smallest and most densely populated country in Central America; its coast has an approximate length of 320 km, 29 municipalities and more than 700 000 inhabitants. In El Salvador there were 15 recorded tsunamis between 1859 and 2012, 3 of them causing damages and resulting in hundreds of victims. Hazard assessment is commonly based on propagation numerical models for earthquake-generated tsunamis and can be approached through both probabilistic and deterministic methods. A deterministic approximation has been applied in this study as it provides essential information for coastal planning and management. The objective of the research was twofold: on the one hand the characterization of the threat over the entire coast of El Salvador, and on the other the computation of flooding maps for the three main localities of the Salvadorian coast. For the latter we developed high-resolution flooding models. For the former, due to the extension of the coastal area, we computed maximum elevation maps, and from the elevation in the near shore we computed an estimation of the run-up and the flooded area using empirical relations. We have considered local sources located in the Middle America Trench, characterized seismotectonically, and distant sources in the rest of Pacific Basin, using historical and recent earthquakes and tsunamis. We used a hybrid finite differencesfinite volumes numerical model in this work, based on the linear and non-linear shallow water equations, to simulate a total of 24 earthquake-generated tsunami scenarios. Our results show that at the western Salvadorian coast, run-up values higher than 5 m are common, while in the eastern area, approximately from La Libertad to the Gulf of Fonseca, the run-up values are lower. The more exposed areas to flooding are the lowlands in the Lempa River delta and the Barra de Santiago Western Plains. The results of the empirical approximation used for the whole country are similar to the results obtained with the high-resolution numerical modelling, being a good and fast approximation to obtain preliminary tsunami hazard estimations. In Acajutla and La Libertad, both important tourism centres being actively developed, flooding depths between 2 and 4 m are frequent, accompanied with high and very high person instability hazard. Inside the Gulf of Fonseca the impact of the waves is almost negligible.