Tsunami Risk Map Research Articles

GIS Based Tsunami Risk Assessment

Tsunami is a coastal hazard which occur due to undersea earthquakes, Meteorite falls, volcanic eruptions or even nuclear weapon operations. The tsunami hazard which occurred in December 2004 was generated due to an undersea earthquake 400m west of northern Sumatra and it inundated coastal areas of Indonesia, Sri Lanka, Thailand and India. This hazard became one of the worst disasters in the history resulting in over thirty thousand fatalities and over seventy thousand house damage in Sri Lanka. This study is focused towards creation of GIS based Tsunami risk map for Galle city which was badly hit by the 2004 Tsunami. Tsunami vulnerability was assessed using weighted overlay spatial method with input parameters of population density, sex ratio, age ratio, disability ratio and damaged building ratio. Tsunami hazard map was developed based on tsunami inundation map which was published by Coastal research and design, costal conservation and resource management department with assistant from Disaster management centre using the Cornell Multigrid Coupled Tsunami Model (COMCOT). Vulnerable and hazard maps were analysed and incorporated to develop final risk map using GIS tool. Keywords GIS; Tsunami Inundation Map; Tsunami Risk Map; Vulnerability; Disaster

Case study: mapping the tsunami-hazard zone in the Pasir Jambak sub-district, in Padang, Indonesia

A tsunami hazard is an adverse event that causes damage to properties and loss of life. The problem in assessing a tsunami risk zone for a small area is significant, as available tsunami inundation zone data does not give detailed information for tsunami inundation and run-up in every nested grid. Hence, this study aims to establish a tsunami risk map in the Pasir Jambak sub-district, Padang, Indonesia. The map was carried out in every nested grid point of the area and on a large scale (1:5,000). The TUNAMI N3 program was used for the simulation of the tsunami inundation. A tsunami assessment was made through simulations in nine scenarios of fault parameter data for Sipora block earthquakes. The result of the study provides a tsunami inundation map. Furthermore, this tsunami inundation map can be used for communities, local authorities, government, and others for many studies, and decision-makers can come up with mitigation plans for a small study area.

Numerical Prediction Of Foils Configuration In A Design of Buoy Glider System For Supporting Tsunami Early Warning

Geographically, Indonesia is a disaster-prone country, with the potential to cause damage to public infrastructure not only cause enormous loss of life. Based on the tsunami risk map released by BNPB in 2018, it needs more attention so that mitigation can be implemented properly. It necessary to revitalize nationally developed by BPPT the buoy-based early warning system for tsunami disasters. Early generation tsunami buoy designs were successfully developed and operated in several waters in Indonesia. In order to improve the performance of the tsunami buoy, a new vehicle system known as the Wave Buoy Glider (WBG) is proposed. It is hoped that this WBG design can cover a wider monitoring area as well as more wave elevation measurement data related to tsunami events. In this research some of the buoy glider-design parameters such as sizes and configurations of foil are studied in order to obtain the optimal pulling force of the wave glider to the surface floater. A numerical calculation using the CFD technique is used to determine the hydrodynamic force. So that from this study, it can be seen that an increasing number used foils, the drag and lift forces also tend to increase. The larger the span foil, the greater the value of the drag and lift forces, especially at the larger AoA angle. The positive values of drag forces at any lift forces confirm that wave glider always move forward with every vertical movement of the floater.

Assessment Of Tsunami Hazard In Sabah – Level Of Threat, Constraints And Future Work

The coastal areas of Sabah are exposed to far-field earthquake-induced tsunamis that could be generated along the trenches of Manila, Negros, Sulu, Cotabato, Sangihe and North Sulawesi. Tsunami simulation models from these trenches indicated that tsunami waves can reach the coast of Sabah between 40 and 120 minutes with tsunami wave heights reaching up to 3 m near the coast. The level of tsunami threat is high in southeast Sabah due to its narrow continental shelf and proximity to tsunami source in the North Sulawesi Trench. The level of tsunami threat is moderate in north and east Sabah due to their proximity to tsunami source in the Sulu Trench. The level of tsunami threat is low in west Sabah due to its distant location to tsunami source from the Manila Trench. While tsunamis cannot be prevented, its impact on human life and property can be reduced through proper assessment of its threat using tsunami simulation models. Unfortunately, constraints remain in producing a reliable tsunami inundation models due to the lack of high-resolution topography and bathymetry data in Sabah and surrounding seas. It would be helpful if such data can be acquired by the relevant government agencies, at least first, in high threat-level areas, such as Tawau and Semporna districts. In order to properly plan mitigation measures tsunami risk mapping should be intensified in high threat-level areas. The locations of settlements (including water villages), population concentrations, types of buildings and houses, road system, drainage system, harbours, jetties and vegetations (including mangroves) need to be mapped in great detail. Based on the detailed tsunami risk map, targeted vulnerable communities could be given continuous and intensive education and awareness on basic tsunami science and tsunami hazard preparedness.

Tsunami Vulnerability and Risk Assessment of Banda Aceh City through ArcGIS Software

This research produced a tsunami risk map of village’s community in Banda Aceh from a low level to a high level risk. Disaster risk analysis techniques involve a set of multi-criteria and Geographic Information Systems (GIS). GIS is used as a method to evaluate the multi-criteria which are made into spatial data and combining them into a risk map. Disaster risk assessment involves two factors: the tsunami hazard assessment and vulnerability of community. Tsunami hazard’s level is measured based on the map of the tsunami’s intensity by the number of damaged buildings that is produced by JICA study team on the Indian Ocean Tsunami in 2004, while the vulnerability of community is evaluated from hazard exposure and coping capacity of society in social, economic and physical dimension. Result of study shows two villages that have an extremely high degree of risk, 36 villages have a high degree of risk, 11 villages have a medium risk, 12 villages have a low risk and 29 villages have no risk at all.

Satellite image analysis and GIS approaches for tsunami vulnerability assessment

Dynamic interactions of the land zone and the ocean, human activities, and also natural hazards such as tsunamis can affect the changing of coastal areas. Tsunami historical events illustrated that the topographic elevation of the coastal area could be important physical parameters for creating tsunami vulnerability areas. The integrated approaches of spatial multi-criteria in the term of Geographical Information System (GIS), the analysis of satellite image, and social parameter analysis were used to map the risk area due to tsunami. This study tried to assess the distribution of tsunami vulnerability area in coastal area of Banten, western part of Java Island, Indonesia. The study applied GIS analysis, satellite image analysis, and the integration of participatory approaches through Analytical Hierarchy Process for the tsunami vulnerability assessment. Vulnerability parameters applied elevation, slope, coastal proximity, coastal shape, and land use is divided into five classes of vulnerability. Based on the land use parameter, plantation area was the widest area included in the category of medium class of tsunami vulnerability, while the very high class of tsunami vulnerability was the irrigated rice field. Very high vulnerability areas were found in the west coastal areas of the sub-districts of Labuan Pagelaran, Patia, Sukaresmi, and Panimbang. The results illustrated in this study can be used as one of the important basic information for creating tsunami risk map. SIG based analysis can aid in a wide range of disaster assessment and facilitate regional planning for management and mitigation of natural disasters such as tsunamis.

Identifikasi dan model ruang terbuka hijau sebagai ruang evakuasi bencana alam gempa bumi berbasis SIG di kawasan Sanur, Denpasar, Bali

Identification and model on green open space as evacuation area of earthquake at Sanur, South Denpasar, Bali. Bali Island is one of Indonesia's seismotectonics as it is passed through the Mediterranean mountain range and the subduction zone between the Eurasian Plate and the Indo-Australian Plate. The southern area of Bali is vulnerable to earthquake and one of the most vulnerable to the earthquake is Sanur. Sanur area has an area of 10,57 km² or 1.057 hectares with a population of 28.527 inhabitants. Therefore, earthquake mitigation such as physical mitigation is to utilize green open space as an evacuation area is considered to be important. The purpose of this research is to identify the suitability of green open space as an evacuation area and to determine the green evacuation open space concept model. This research used satellite image interpretation and field survey methode. The data used is data of the earthquake center point throughout in Sanur along with potential tsunami risk map, green open space map and accessibility map. The parameters used were green open space width of at least 500 m², types of green open space, accessibility, and potential earthquake and tsunami. Result showed that the green open space which suitable as an evacuation area was about 292 hectar and not suitable is 93 hectar. Furtheremore, the suitable green open space evacuation map was generated into two evacuation space concept. There were micro evacuation space and macro evacuation space. The micro evacuation space focuses on individual rescue while the macro evacuation space focuses on mass rescue.

Peta Zonasi Tsunami Indonesia

Kepulauan Indonesia berada pada daerah rawan gempa, dengan resiko gempa yang dapatmenyebabkan tsunami dapat terjadi pada berbagai tempat di setiap pulau. Gempa bumi yangmenyebabkan gelombang tsunami dapat menghancurkan kota-kota pada daerah pesisir pantai. Olehkarena itu peta rawan tsunami terus dikembangkan, untuk memberikan informasi mengenai tinggirayapan tsunami untuk keperluan desain bangunan maupun instansi pemerintah di seluruh kepulauanIndonesia. Peta rawan tsunami berdasarkan kejadian gempa yang menyebabkan tsunami pada suatuwilayah, dan menghitung tinggi rayapan tsunami dengan menggunakan rumus Katyusuki Abe (1995).Peta rawan tsunami dibagi menjadi 5 zona, yaitu zona 0 dengan ? = 0,00 – 0,29, zona 1 dengan ? =0,30 – 0,49, zona 2 dengan ? = 0,50 – 0,69, zona 3 dengan ? = 0,70 – 0,89 dan zona 4 dengan ? =0,90 – 1,10.

Spatial multi criteria approach for tsunami risk assessment

Tsunami risk is defined as mathematical product between vulnerability and hazard. Tsunami risk also refers to the estimated loss from a given hazard to a given element at risk, and it is defined as a combination of tsunami hazard, tsunami vulnerability, exposure, and event probability. Besides tsunami vulnerability, tsunami risk is assessed by a number of criteria. This study applies the combination of element at risk to assess tsunami risk area along coastal area of East Java Indonesia. The study introduces the spatial multi-criteria analysis into tsunami risk assessment along with the existing perspective evolving the role of GIS. In this study, the existing vulnerability parameter was analysed and evaluated. The analysis was done using GIS-based spatial multi criteria approach. All parameter were analysed through weighted overlay using analytical hierarchy process and geospatial analysis. The results are provided as thematic maps of tsunami vulnerability map and tsunami risk map. Tsunami risk maps as a result from this study illustrate five levels of risk from very low to very high based on geospatial analysis. It describes that coastal area with low elevation was at high risk to tsunami, similar to that indicated in tsunami vulnerability map. Coastal area with high density of vegetation describes a low level tsunami risk. The existence of river and other water stream along coastal area are also important parameters in generating tsunami risk map. Risk map highlights the coastal areas with a strong need for evacuation capacities, including evacuation route and evacuation building.

INTEGRATED SATELLITE REMOTE SENSING AND GEOSPATIAL ANALYSIS FOR TSUNAMI RISK ASSESSMENT

Tsunami risk is defined as a combination of the danger posed by tsunami hazard, thevulnerability of people to an event (exposure), and the probability of destructive tsunami or likelihood of thetsunami occurring. Tsunami risk is also defined as the mathematical calculation of tsunami vulnerability andtsunami hazard, and it can be assessed using a spatial multi-criteria. The study applied the combination of theelement at risk to assess tsunami risk area along the coastal area of East Java Indonesia off the Indian Ocean.Remote sensing approach followed by geospatial analysis into tsunami risk assessment along with the existingperspective evolving the role of Geographical Information System. The existing physical vulnerabilityparameter was analyzed and evaluated. All parameters in both tsunami vulnerability and tsunami riskassessment were analyzed through weighted overlay in geospatial analysis, in which the criteria’s weight wascalculated through Analytical Hierarchy Process. The results were provided as thematic maps of tsunamivulnerability and tsunami risk. Tsunami risk map described five classes of risk from very low to very highbased on the geospatial analysis. It described that coastal area with low elevation identified as high risks to thetsunami. The coastal area with high density of vegetation described a low level of tsunami risk. The existenceof river and another water canals along coastal area were also identified as important parameters in generatingtsunami risk map. Risk map highlights the coastal areas with a strong need for evacuation capacities, includingevacuation route and evacuation building.

Analysis of tsunami disaster map by Geographic Information System (GIS): Aceh Singkil-Indonesia

Tsunami risk map is used by stakeholder as a base to decide evacuation plan and evaluates from disaster. Aceh Singkil district of Aceh- Indonesia’s disaster maps have been developed and analyzed by using GIS tool. Overlay methods through algorithms are used to produce hazard map, vulnerability, capacity and finally created disaster risk map. Spatial maps are used topographic maps, administrative map, SRTM. The parameters are social, economic, physical environmental vulnerability, a level of exposed people, parameters of houses, public building, critical facilities, productive land, population density, sex ratio, poor ratio, disability ratio, age group ratio, the protected forest, natural forest, and mangrove forest. The results show high-risk tsunami disaster at nine villages; moderate levels are seventeen villages, and other villages are shown in the low level of tsunami risk disaster.

A new GIS-based tsunami risk evaluation: MeTHuVA (METU tsunami human vulnerability assessment) at Yenikapı, Istanbul

Istanbul is a mega city with various coastal utilities located on the northern coast of the Sea of Marmara. At Yenikapi, there are critical vulnerable coastal utilities, structures, and active metropolitan life. Fishery ports, commercial ports, small craft harbors, passenger terminals of intercity maritime transportation, waterfront commercial and/or recreational structures with residential/commercial areas and public utility areas are some examples of coastal utilization that are vulnerable to marine disasters. Therefore, the tsunami risk in the Yenikapi region is an important issue for Istanbul. In this study, a new methodology for tsunami vulnerability assessment for areas susceptible to tsunami is proposed, in which the Yenikapi region is chosen as a case study. Available datasets from the Istanbul Metropolitan Municipality and Turkish Navy are used as inputs for high-resolution GIS-based multi-criteria decision analysis (MCDA) evaluation of tsunami risk in Yenikapi. Bathymetry and topography database is used for high-resolution tsunami numerical modeling where the tsunami hazard, in terms of coastal inundation, is deterministically computed using the NAMI DANCE numerical code, considering earthquake worst case scenarios. In order to define the tsunami human vulnerability of the region, two different aspects, vulnerability at location and evacuation resilience maps were created using the analytical hierarchical process (AHP) method of MCDA. A vulnerability at location map is composed of metropolitan use, geology, elevation, and distance from shoreline layers, whereas an evacuation resilience map is formed by slope, distance within flat areas, distance to buildings, and distance to road networks layers. The tsunami risk map is then computed by the proposed new relationship which uses flow depth maps, vulnerability at location maps, and evacuation resilience maps.

GIS Based Tsunami Risk Assessment in Weligma, Sri Lanka

A tsunami is a natural coastal hazard generated in the deep ocean as a result of an earthquake, volcanic activity, submarine landslide or meteoritic impact. The 26th Dec. 2004 earthquake off the west coast of Sumatra, Indonesia generated one of the deadliest tsunami in history. It demolished the coastal areas of Indonesia, Sri Lanka, India, and Thailand, as these countries located shadow zone of this tectonic belt. Over thirty thousand loss their lives and also millions of worth extensive property damaged. As Sri Lanka situated in a shadow zone of the earthquake generated belt preparedness is very important factor. The study focused towards creation of a Tsunami risk map for Weligama area. The numerical simulation of tsunami inundation was carried out using ComMIT model with the major input parameters of earthquake source parameters, topography and bathymetry data. The December 2004 Sumatra Earthquake source parameters were used for generation, propagation, and coastal amplification of the tsunami waves and finally the inundation extent and water level was obtained to prepare large scale action maps on tsunami inundation to protect the coastal communities. The GIS tool has been used to incorporate the tsunami inundation depth to prepare the final tsunami risk map. Reliability of model results was compared with the field data and a high resolution QuickBird images with pre and post tsunami. The results from this study will be useful for long - term planning in vulnerable coastal communities and providing early warnings to take precautions to reduce impacts of tsunami in future.

Simulation systems for tsunami wave propagation forecasting within the French tsunami warning center

Abstract. A model-based tsunami prediction system has been developed as part of the French Tsunami Warning Center (operational since 1 July 2012). It involves a precomputed unit source functions database (i.e., a number of tsunami model runs that are calculated ahead of time and stored). For the Mediterranean basin, the faults of the unit functions are placed adjacent to each other, following the discretization of the main seismogenic faults. An automated composite scenarios calculation tool is implemented to allow the simulation of any tsunami propagation scenario (i.e., of any seismic moment). Uncertainty on the magnitude of the detected event and inaccuracy of the epicenter location are taken into account in the composite scenarios calculation. Together with this forecasting system, another operational tool based on real time computing is implemented as part of the French Tsunami Warning Center. This second tsunami simulation tool takes advantage of multiprocessor approaches and more realistic seismological parameters, once the focal mechanism is established. Three examples of historical earthquakes are presented, providing warning refinement compared to the rough tsunami risk map given by the model-based decision matrix.

Re-assessing volcanic hazard maps for improving volcanic risk communication: application to Stromboli Island, Italy

Please click here to download the map associated with this article. Hazard and risk maps are tools for both mitigating against risk and informing and preparing the general public. Recent studies have highlighted that volcanic hazard and risk maps used during emergencies can be difficult to interpret. Our research focuses on evaluating and improving the efficacy of currently available maps of Stromboli volcano on Stromboli island (Italy) for the communication of volcanic hazard and risk information. Stromboli is an active volcano characterised by persistent explosive activity, sporadic lava effusions and landslides on the volcanos northwestern flank, which sometimes generates tsunamis, most recently in 2002. This study used semi-structured interviews conducted with local legislators, administrators and ‘enforcers’ to understand their perceptions of available risk information; to evaluate the respondents mental spatial maps; and to determine the most important components in encouraging risk-reducing behaviour in a hazardous situation. Respondents were asked to evaluate a contour map, an aerial photograph, a digital elevation model (DEM) and an innovative 3D tsunami risk map. These results enabled the development of different volcanic risk maps for use by ‘experts’ and ‘tourists’ using a contour map and a DEM (Scale 1:12.500). A 3D map focused on the tsunami risk (Scale 1:6.500) area was also produced.

The effects of the 1755 Lisbon earthquake and tsunami on the Algarve region, southern Portugal

ABSTRACTThe 1755 Lisbon earthquake (magnitude c. 8-5Mw) killed between 15,000 and 20,000 people, of whom an estimated 1020 lived in the Algarve. The earthquake cost Portugal between c. 32 and 48% of its Gross Domestic Product, probably making it financially the greatest natural catastrophe to have affected western Europe. Using a combination of archival information and data collected in the field, this article discusses the devastating effects of the earthquake and tsunami on the economy, society and major settlements in the Algarve, and the recovery of the region in the years that followed. Today the Algarve is one of Europe's principal tourist destinations and a region vital to the Portuguese economy. The 1755 earthquake was not a one-off event and the Algarve, which now houses a resident population of over 400,000 – a figure that more than doubles with tourists in the summer months – is highly exposed to earthquakes and tsunamis. An earthquake of similar size (minimum estimated recurrence 614±105 years), is viewed as a worst-case future scenario. Although strict building codes which apply to the whole country were pioneered in Portugal following the 1755 earthquake, and have been revised on many occasions, there is a recognised need for more detailed hazard maps and emergency plans for the Algarve. These have already been produced for Lisbon and in the Algarve a start has been made, where a tsunami risk map has recently been completed for Portimào concelho1 (i.e. county).

Misconception Of Run-Up Definition And Its Implication To Tsunami Risk Assessment A Case Study In Pacitan Coastal Area, Indonesia

This article aims to build the similar understanding of run-up concept and to review the of t,'}iinami risk in Pacitan released by Balai Pengkajian Dinamika Pantai (BPDP)-BPPT Indonesia. We also propose similar understanding of risk definition related to the natural hazards, such as tsunami. The investigation used comparison method between 2 maps, i.e. tsunami risk map by BPDP and our tsunami risk map. Based on the comparison result, we found a misconception of rim-up in the tsunami risk map produced by BPDP. There is no differentiation between run-up and water-height over the land. It should be revised to avoid it from the incorrect rim-up definition. We also found if it was also mentioned as a of t.\imami risk analysis while the result was not performed in that map. Therefore, it is necessGlY to understand the run-up concept and risk concept first prior to map those phenomena.