Tsunami Hazard Map Research Articles

Analysing Civilian Video Footage for Enhanced Scientific Understanding of the 2011 Tohoku Earthquake and Tsunami, Japan, with Implications for PNG and Pacific Islands

Approximately 70% of global tsunamis are generated within the pan Pacific Ocean region. This paper reports on detailed analysis of civilian video footage from the 2011 Tohoku earthquake, Japan. Comprehensive scientific analysis of tsunami video footage can yield valuable insights into geophysical processes and impacts. Civili22an video footage captured during the 2011 Tohoku, East Honshu, Japan tsunami was critically examined to identify key tsunami processes and estimate local inundation heights and flow velocity in Kesennuma City. Significant tsunami processes within the video were captured and orientated in ArcGIS Pro to create an OIC (Oriented Imagery Catalogue). The OIC was published to ArcGIS Online, and the oriented imagery was configured into an interactive website. Flow velocity was estimated by quantifying the distance and time taken for an object to travel between two known points in the video. Estimating inundation height was achieved by taking objects with known or calculable dimensions and measuring them against maximum local inundation height observations. The oriented imagery process produced an interactive Experience Builder app in ArcGIS Online, highlighting key tsunami processes captured within the video. The estimations of flow velocity and local inundation height quantified during video analysis indicate flow speeds ranging from 2.5–4.29 m/s and an estimated maximum local run-up height of 7.85 m in Kesennuma City. The analysis of civilian video footage provides a remarkable opportunity to investigate tsunami impact in localised areas of Japan and around the world. These data and analyses inform tsunami hazard maps, particularly in reasonably well-mapped terrains with remote access to landscape data. The results can aid in the understanding of tsunami behaviours and help inform effective mitigation strategies in tsunami-vulnerable areas. The affordable, widely accessible analysis and methodology presented here has numerous applications, and does not require highly sophisticated equipment. Tsunamis are a significant to major geohazard globally including many Pacific Island states, e.g., Papua New Guinea, Solomon Islands, and Tonga. Video footage geoscientific analysis, as here reported, can benefit tsunami and cyclone storm surge hazards in the Pacific Islands region and elsewhere.

Generating Evacuation Route for Tsunami Evacuation Based on Megathrust Scenario Hazard Model in Palabuhanratu Village, Sukabumi, West Java

Palabuhanratu Village is one of the villages in Sukabumi, West Java, that is susceptible to earthquake and tsunami risks. This research intends to revise the tsunami hazard map, undertake a spatial analysis of the distribution of evacuation sites, and identify optimal tsunami evacuation routes. The tsunami hazard map was updated using tsunami modeling with COMCOT based on the worst-case scenario of potential magnitude moment 8.8 for the Megathrust segment in the south of West Java from PuSGeN. This modeling was used to predict the worst probable tsunami impact. On the basis of field survey data regarding the location of evacuation sites, evaluation of the distribution of evacuation sites was conducted. In addition, service area analysis is utilized to assess the service area of the present evacuation site in relation to each hamlet in Palabuhanratu village. Approximately 57.33 percent of the town could be affected by a tsunami, according to the findings of this study. The greatest tsunami height along the coast is expected to be between 18 and 22 meters, and the arrival time is 22 minutes. From a total of 35 hamlets, we determined that two hamlets in the Palabuhanratu village area were not harmed by the tsunami. Because not everyone can reach the evacuation location in time, the findings of this study show the need for an additional vertical evacuation site.

Pemetaan Tingkat Kerawanan Bencana Tsunami di Pesisir Barat Daya Provinsi Banten

Indonesia is one of the countries that has a high level of natural disasters in the world because of Indonesia's location and geographical position in the rings of fire. One of the most vulnerable disasters in Indonesia is earthquakes, volcanic eruptions to tsunami waves (Mukhtasor , 2007). Based on data from the BNPB on December 22 2018, there was a tsunami disaster in the southwest coast of Banten to the coast of Lampung caused by the eruption of Mount Anak Krakatau. The purpose of this study are to create tsunami hazard map on the southwest coast of Banten Province by using a Geographic Information System (GIS) and then identify which areas are in a very vulnerable class. This research was conducted in February 2020 until May 2020. The analytical method used was descriptive analysis, map overlay analysis, and qualitative analysis. The stages include the preparation of maps and supporting data using the help of Global Mapper 8.0 software, the determination of influential parameters, analysis of tsunami prone areas based on the parameters that affect, and determination of tsunami prone areas. The process of determining tsunami-prone areas is done through a process of weighting and scoring of influential parameters, then overlapping with the help of ArcGis 10.7 software to get a map of the level of tsunami hazard. The factors in this study that affect tsunami hazard are land height, land protection, distance from the tsunami source, coastline shape, and the presence of barrier islands. The total area classified as very vulnerable is around 19,94 km2 on the southwest coast of Banten Province. This indicates the need for disaster management through crisis management and risk management based on more valid research.

TSUNAMI HAZARD MODELING IN THE COASTAL AREA OF KULON PROGO REGENCY

Kulon Progo Regency is located in the southern part of Java Island, one of Indonesia's areas that is prone to tsunami disasters. Kulon Progo Regency is prone to tsunamis because it faces a subduction zone in the Indian Ocean. Therefore, it is necessary to model tsunami inundation and map the tsunami hazard zone in the Kulon Progo coastal area. This study aims to model tsunami inundation and produce a tsunami hazard map with a tsunami height scenario of 5 meters and 10 meters. The method used in modeling tsunami inundation is using a mathematical calculation developed by Berryman-2006 using the parameters of the coefficient of surface roughness, slope, and the height of the tsunami at the coastline. The estimated tsunami inundation area is classified into a tsunami hazard index using the fuzzy logic method resulting in an index of 0 – 1, which is then divided into three hazard classes. The results of the tsunami hazard mapping with the 5 meters scenario are 15 villages in 4 sub-districts included in the hazard zone with a total area of 20672,34 Ha affected. The results of the tsunami hazard mapping with a 10 meters scenario are 26 villages in 4 sub-districts with a total area of 53042,66 Ha affected. The results of this research can be used as basic information for disaster mitigation.

Tsunami Hazard Mapping and Evacuation Path Determination using field Survey and Geographical Information Systems at Widarapayung Wetan, Cilacap

In 2006, a tsunami hit Pangandaran, and its effects were felt in Cilacap. There were 664 fatalities, 498 injuries, and 55 million dollars in damages, and 1623 homes were destroyed or severely damaged due to the tsunami. Furthermore, the village of Widarapayung was among those devastated by the tsunami, which reached a height of up to 5 meters and claimed the lives of 12 people. In addition, Widarapayung is a popular tourist destination and one of the venues for 2019’s professional surfing events. Therefore, disaster prevention measures are essential to lessen the impact of disasters and save lives. The objective of this study is to assess the vulnerability of the Widarapayung Wetan area to a tsunami and make recommendations for evacuation routes and regional infrastructure development to reduce casualties and damage. This research utilized COMCOT to model the megathrust segment with a possible magnitude of 8.7, with worst-case values acquired from the catalog PuSGeN 2017. Additionally, the data on topography and bathymetry collected by DEMNAS and BATNAS are utilized in this investigation. The modeling results indicated a 50-minute arrival time for the tsunami waves, a maximum run-up height of 14-18 meters, and a submerged area of roughly 4.57 km2. In addition, the most effective evacuation routes were determined by combining the outcomes of field surveys and Geographic Information System simulations. This research will provide local governments with helpful information for making informed decisions about infrastructure and spatial development in the future.

Tsunami Risk Assessment on Public Facilities in Southern Part of Bantul Regency, Yogyakarta

The southern part of Java Island is susceptible to tsunamis as its role as a subduction zone between Indo-Australian and Eurasian plates. On July 17, 2006, a tsunami struck Java's south coast triggered by an earthquake and affected more than 300 km of shoreline, as well as claimed more than 730 casualties. It is important to assess the risk in the southern part of Java. This research aims to analyze tsunami risk assessments on public facilities in the southern part of Bantul Regency, Yogyakarta. The Tsunami hazard map was created by using tsunami modeling from BMKG. Public facilities footprint such as health facilities, religious facilities and school were derived from data provided by Open Street Map (OSM). The Papathoma Tsunami Vulnerability Assessment (PTVA) model, specifically developed to estimate the relative vulnerability of buildings to tsunami hazards, is used to generate a building vulnerability map. A geographic information system (GIS) was utilized to calculate and visualize the hazard, vulnerability, and risk map. A total of 394 buildings were analyzed with the results that public facilities in three sub-districts, namely Srandakan, Sanden and Kretek, had varying levels of building vulnerability ranging from minor, moderate, average and high with RVI values ranging from 1.5 to 3.4. Additionally, tsunami risk assessment of public facilities indicates that buildings within Bantul Regency are categorized as having very high, high, moderate, or low levels of building risk.

Integrating Topographic and Bathymetric Data for High-Resolution Digital Elevation Modeling to Support Tsunami Hazard Mapping

Tsunamis pose a threat to coastal communities. Flooding from tsunami-generated waves can cause extensive damage to infrastructure, and in some cases may even lead to loss of human life. Sea level rise due to climate change is expected to exacerbate the risk of flooding hazards. In British Columbia (BC), coastal communities are particularly vulnerable to tsunamis because of their proximity to the Alaska-Aleutian and Cascadia subduction zones.

Tsunami Hazard Analysis in Likupang Tourism Area, North Sulawesi

The Likupang area, North Sulawesi is one of the super priority tourist destinations launched by the Central Government with the marine tourism sector as the axis. On the other hand, the potential for natural disasters originating from the sea is unavoidable so it needs to be one of the considerations in the process of developing disaster-responsive tourist areas. A tsunami hazard analysis study is first step in disaster mitigation planning. The study is in the form of tsunami modeling by identifying the worst possible scenario in the Likupang area using COMMIT modeling. The modeling is able to produce parameters such as arrival time, maximum height and tsunami inundation area. These three parameters are used as the basis for mapping the tsunami hazard map. The modeling produces the fastest arrival time, which occurs in the first minute after an earthquake occurs. The maximum height obtained from the modeling is 6.8 meters. The maximum inundation area reached by the tsunami wave is 23.57 km2. The combined results of the five scenarios are presented in hazard maps. The majority of public tourist sites are in the Warning status area, but some private resorts are still in the area with the Major Warning status.

Generating tsunami hazard map with various relief (Land) in Indonesian coastal cities by remote sensing perspective: A preliminary study

Tsunami-prone areas on the western and southern coasts of Sumatra, Java, and Bali are home to more than a hundred million Indonesians. As preliminary research, the main goals of this paper are to present a hazard assessment methodology that identifies areas of high tsunami hazard and the spatial distribution pattern of inundated areas and its energy transfer to the inland with various relief (land) in coastal cities. The methods established here are based on a geographic information system (GIS) approach by combining the numerical modelling, wave height, and remote sensing data. We also examined the variations of spatial hazard distribution with a medium spatial resolution (30 m) among the pilot sites studies. The result stated that medium spatial resolution has limitations to model the inland tsunami inundation and its energy in the plain area. Still, it can model in the dynamic elevation variation. Under the 10 m wave height scenario, the highest mean of inundation depth among four pilot sites is in Kuta (5.9 m with an energy wave (Ewave) of 38.34 MJ), followed by Banyuwangi (5.5 m with Ewave of 33.32 MJ), Pacitan (5m with the Ewave of 27.53 MJ) and Sibolga (3.9 m with the Ewave of 16.75 MJ), respectively.

Effects of Tsunami Shelters in Pandeglang, Banten, Indonesia, Based on Agent-Based Modelling: A Case Study of the 2018 Anak Krakatoa Volcanic Tsunami

On 22 December 2018, the volcanic eruption of Anak Krakatoa in the Sunda Strait, Indonesia, triggered a tsunami causing 437 deaths. The highest death toll and the second highest number of damaged houses were recorded in Panimbang. This study proposes optimum evacuation shelters to reduce the mortality rate. A digital elevation model (DEM) and information dataset are used. The suggested horizontal evacuation shelters (HESs) are places of worship, schools, and government offices. Multimodal agent-based modelling (ABM), to analyse the sensitivity of parameters and the effect of vertical evacuation shelters (VESs) under multiple scenarios, is presented for the volcanic tsunami in December 2018. A tsunami hazard map is created by combining relative weights and parameter scores for topography, slope, and the distance from the shoreline and rivers. In the ABM results, the transportation mode choice depicts a significant decrease in the number of casualties. The mortality rate is sensitive to the milling time caused by delay time τ and agent decision-making time σ. VESs are proposed at the hot spots based on the location of deaths in the sensitivity tests and the high and very-high risk zones in the hazard map. As a result, combinations of VESs and HESs show a decrement in the number of deaths by 1.2–2 times compared to those with HESs only. The proposed VESs in the study area have a significant positive impact on decreasing the mortality rate.

The probability of community-scale building damage and economic loss in Thailand increased after the 2004 Indian Ocean tsunami

Understanding the impacts of tsunamis, especially in terms of damage and losses, is important for disaster mitigation and management. This study aims to estimate the building damage and economic loss (direct and indirect) changes for two periods before and after the 2004 Indian Ocean Tsunami (IOT) on Patong Beach in Phuket Province, Thailand. We begin to produce the tsunami hazard map using the TUNAMI-N2 model and examine the change in buildings during the two periods. Next, the fragility curve established from the 2004 IOT was applied with the hazard map and construction unit cost to estimate the damage losses as direct losses. Then, we adopt the exogenous multiregional input–output (MRIO) table method to distinguish the indirect regional economic losses throughout the country. Finally, the indirect losses are estimated by using the economic structure based on the MRIO table. Our results show that over a 15-year period, the number of buildings in Patong Beach increased by approximately 30% since the 2004 IOT. The greatest increase was observed for hotels/restaurants (18%), followed by houses (10%). The increase in building density affected the water level, increasing in the area close to the coastline while decreasing in the area far from the coastline. This impact reveals that the mean inundation in the whole area is reduced by 4%. Buildings show higher damage in the area close to the coastline, which increased by approximately 10%. Based on the 2004 IOT, the direct damage losses also increased by approximately 58%, in which the highest direct loss was in hotel/restaurant buildings, followed by stores/warehouses. The indirect losses of the inundated building increased by approximately 55% compared with the direct losses from the 2004 IOT. Among the impacted sectors in the MRIO table, the hotel/restaurant sector suffered the highest losses; within this sector, the fishery sector was most affected, followed by the food production sector and then the crop sector. On the regional scale, Bangkok has the highest impact, with the second-highest impact in the east and the next highest impact in the west. To consider the difference between the two periods, the indirect loss increased by 48% and 43% on the sector and regional scales, respectively. Approximately 55% of the overall economic losses were indirect, including the economic impacts of increased construction in the coastal risk area of Phuket Island on Thailand's economy. This approach could be useful for stakeholders and policymakers for future tsunami mitigation in cases at the community scale.

Worst-Case tsunami inundation modeling using high-resolution UAV-DEM in various coastal typologies, case study Gunungkidul coastal area

A tsunami is a significant threat to the coastal community. The southern coast of Java is considered a tsunami-prone area due to its location facing the Indian Ocean. Gunungkidul Regency in Yogyakarta Special Region is well known for its attractive coastal tourism. Numerous visitors are exposed to tsunami hazards that can be occurred unpredictably. The unavailability of a reliable tsunami hazard map leads to an ineffective evacuation plan. This study aims to implement UAV data for tsunami hazard mapping in different coastal typologies. This study was conducted at Baron Beach, Drini, and Wediombo. The tsunami inundation model was generated from high-resolution UAV-DEM. The worst inundation scenario was set at 12 meters. Based on the results, Baron and Drini are considered highly susceptible to tsunami hazards due to their topographic conditions, mostly located on the flat karst valley. Wediombo is categorized as the primary coast that is formed by the volcanic process. The inundation model at Wediombo only covers a small extent of the area. Volcanic origin morphology formed an undulating to hilly topography that plays an essential role as a natural barrier for the tsunami. However, minimum access and narrow pedestrian street become serious disadvantages for tsunami evacuation route planning at Wediombo Beach.

Regional Probabilistic Tsunami Hazard Analysis for the Mexican Subduction Zone From Stochastic Slip Models

AbstractThe Mexican subduction zone is prone to large earthquakes that impact populated coastal and inland cities due to strong shaking and can generate potentially disastrous tsunamis. Even though the population and infrastructure on the Mexican Pacific coast may experience tsunamis, only sparse instrumentation and scarce tsunami observations exist for both, historical and instrumental, records. This study presents a probabilistic tsunami hazard analysis that can provide information for managing and assessing risks in the region. We use ensembles of numerical tsunami simulations to estimate the probability of exceedance of the maximum tsunami amplitudes, considering the contribution of near sources and slip heterogeneities, for return periods of 100, 500, and 1,000 years. According to 7,946 simulated scenarios, the amplitudes can reach up to 9.5 m along the shoreline. Moreover, tsunami hazard maps, curves, and disaggregation analyses reveal critical hazard points along the coasts of the states of Jalisco, Colima, Michoacán, Guerrero, and Oaxaca.

Incorporating Universal Design into Tsunami Modeling Results for Cascadia Subduction Zone Faults to Create an Inundation Map and Universally Designed Evacuation Map for Port Angeles, WA

Current tsunami hazard inundation and evacuation maps in the Puget Sound are based primarily on Cascadia and Seattle fault tsunamis. The standard evaluation process for tsunami impacts focuses on elevation and hypothetical fault rupture of known and predicted earthquakes. However, there are several known tsunami deposits in the Puget Sound that are not from Cascadia or Seattle fault tsunamis, potentially from other faults within the region, that could affect tsunami mitigation. Work to understand newly discovered crustal deformation and faults in Puget Sound is ongoing, therefore evacuation and inundation maps need to be updated to include these new faults and integrate universal design more broadly. Methods involved using GeoClaw software to map tsunamis from the Cascadia Subduction Zone (CSZ), Leech River fault (LRF), and Utsalady Point fault (UPF). Modeled tsunamis determined the overall inundation of Port Angeles, Washington through a wide range of earthquake inputs of magnitude, proximity, and recurrence. The output simulations were evaluated with key components of universal design to create a new tsunami hazard map. Comparison between the universal design-based map to current the tsunami hazard map allowed for an evaluation of the current evacuation map. This evaluation can improve the assessment of bridges and other evacuation mechanisms. This research can contribute to future tsunami hazard map revisions saving lives, can help with emergency management planning, and spur reevaluating evacuation plans within the tsunami impact area.

Tsunami Hazard Mapping and Loss Estimation in Yogyakarta International Airport Area

Yogyakarta International Airport and Temon District in Regency of West Progo are located on the southern coast of Java island with the potential for tsunami disaster. The BNPB (National Agency for Disaster Relief) data along the southern coast of Java is a high priority region with high tsunami risk. This study aims to predict and analyze tsunami disasters with a height of 15 meters and 20 meters. To show the element of risk exposed using the overlay technique with a tabulated system using GIS software (Autocad and Global Mapper) to map the affected map. With a total area of study of 5,872 hectares in the 15-meter-wide scenario of the area reaching 2,836 hectares in 12 villages, the 206-hectare 206-acre scenario covers 14 villages. For the physical aspect, the 15-meter scenario is located at 6517 dilapidated buildings and the 20-meter scenario is at 9697 buildings. For the social aspect, there are 281,345 people for the 15-meter scenario and 295,554 for the 20-meter scenario. For TES Evacuation (TEA Evacuation Station) and TEA (Final Evacuation Station), for TES a total of 19 points that are TES based at Aerotropolis and TEA are on a hillside 4 kilometers from the coastline.

Microzoning Tsunami Hazard by Combining Flow Depths and Arrival Times

Tsunami hazard is typically assessed from inundation flow depths estimated from one or many earthquake scenarios. However, information about the exact time when such inundation occurs is seldom considered, yet it is crucial for pedestrian evacuation planning. Here, we propose an approach to estimating tsunami hazard by combining tsunami flow depths and arrival times to produce a nine-level, qualitative hazard scale that is translated into a simple tsunami hazard map. To do this, one of the most populated regions of the coast of Chile is considered as the sample site, using a large set of 2,800 tsunamigenic sources from earthquakes with magnitudes in the rangeMw8.6−9.2, modeled from generation to inundation at high resolution. Main outcomes show great dependency of the hazard categorization on the tsunami time arrival, and less to the flow depths. Also, these results demonstrate that incorporating different sources of variability such as different earthquake magnitudes and locations as well as stochastic slip distributions is essential. Moreover, this proof-of-concept exercise clearly shows that the qualitative hybrid categorization of the tsunami hazard allows for its more effective understanding, which can be beneficial for designing mitigation strategies such as evacuation planning, and its management.

Mapping Tsunami Vulnerability Area for Bacan Sub-District and Its Surroundings – North Maluku Province

This research aims to explore tsunami-prone areas in the Bacan and South Bacan districts of South Halmahera Regency. The findings of this research are planned to assist all stakeholders, particularly in developing disaster risk assessment sheets. To estimate the tsunami hazard map, the susceptibility of the elevation, slope, river distance, and coastal distance was collected. Overlaying thematic maps were used assisted by GIS software. The result shows that the low and very low tsunami vulnerability areas were safe from tsunami inundation predominate in the Eastern part and Northern part of the study area while the area designated as very vulnerable covered 157,10 hectares. These locations may have sustained the most damage from a tsunami catastrophe due to their proximity to the sea, low terrain and slope, and dense population. In consideration of the tsunami disasters in Aceh, we anticipate that tsunami risk maps will support in the initiation of humanitarian and development activities in North Maluku Province.

PHYSICAL AND NUMERICAL MODELING OF TSUNAMI INUNDATION IN COASTAL URBAN AREA

This coastal hazards emphasize the need for engineers to understand the fundamental processes causing damage and the potential of maximum damage in order to design coastal communities with increased resilience to tsunami events. Common methods used to evaluate local conditions caused by tsunamis include post-disaster reconnaissance field surveys, numerical modelling, and laboratory experiments. Behavior of land side tsunami, inundation, is not well known as well as the fluid forcing, fragility characteristics and accuracy of tsunami hazard mapping. This study targets to understand local tsunami behavior in a city scale including complex buildings and improve modelling of tsunami inundation in an urban area. Laboratory experiments are an essential starting point in the investigation of urban roughness effects on wave propagation and maximum pressures in coastal communities. Physical modelling usually uses solitary wave, bore wave, and wave imitating Nankai Trough Earthquake as a tsunami wave.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/-4niVrzXviE

Analyzing Tsunami Hazard using Numerical Modelling: Study Case Palu, Sulawesi Tengah, Indonesia

The present study aims to assess the Tsunami hazard in Palu due to the future Tsunamigenic event in terms of near-shore and far-field Tsunami runup, inundation height, and Tsunami arrival time along the coast of Palu. A numerical model is developed to simulate propagation and inundation in the study area. Four scenarios are conducted, which consists of the Tsunamigenic earthquake and aerial subsidence as an approach for mimicking hypothetical potential landslide. The outcome from simulation such as inundation height each grid points then calculated with building footprint stored data – derivation data from the terrain model to develop a Tsunami hazard map. Preliminary Tsunami Hazard Map is made to classify the Tsunami hazard level by existing classification added with estimated building impacted and arrival time ashore on each village in Palu City administrative region.

Tsunami hazard assessment for the central and southern pacific coast of Colombia

ABSTRACT Highly destructive tsunamis occurred near the Pacific coast of Colombia in 1906 and 1979. Recent studies have established asperities within the subduction zone in this area, which can cause megathrust earthquakes triggering highly destructive tsunamis. In this study we assess the tsunami hazard in the main populated areas of Colombia Pacific coast by calculating the inundation depth and the maximum tsunami height from major scenario. A deterministic method is applied using slip deficit models and broadband slip models as tsunami sources. Result suggest that, for the worse-case scenario, the maximum deformation of the seafloor is 6.0 m within the Esmaraldas segment ; the maximum height of the tsunami is 4.66 m, 4.34 m and 0.53 m around. Tumaco Island, Morro Island, and Cascajal Island (Buenaventura Bay), respectively. Two to five meters inundation depth were calculated in over 11% and 10% of the total areas of the islands of Tumaco and Morro, respectively. Based on these result, tsunami hazard maps were alaborated and will serve to create tsunami mitigation plans in these areas.