Indian Ocean Tsunami Research Articles

The 2004 Tsunami Impact on Andaman & Nicobar Islands: Consequences and Future Way Forward

The 2004 Indian Ocean tsunami, caused by a powerful undersea earthquake off the coast of Sumatra, resulted in unprecedented destruction across several coastal regions. The Andaman & Nicobar Islands, located near the epicenter, suffered significant loss of life, displacement, and environmental degradation. This paper provides a comprehensive analysis of the tsunami’s impact on the Andaman & Nicobar Islands, detailing the immediate effects, long-term consequences, and rehabilitation efforts. The paper also explores the economic, social, and psychological ramifications of the disaster, particularly on indigenous communities. Looking ahead, it emphasizes the importance of sustainable development, community-based disaster preparedness, and ecosystem restoration to build resilience in the region. The proposed way forward focuses on developing infrastructure that is disaster-resilient, improving disaster management systems, and empowering indigenous communities in rehabilitation efforts to ensure long-term recovery and resilience.

Progress and challenges in implementing the Sendai Framework for Disaster Risk Reduction at sub-national levels: insights from Aceh, Indonesia

ABSTRACT Common gaps in the current reporting system regarding the progress of meeting the targets Sendai Framework for Disaster Risk Reduction (SFDRR) implementation in low- and middle-income countries include (1) systematic bias towards central governments’ interests and narratives; (2) reports suffer from lack of independent process committed to evidence-based reporting; (3) progress reports do not reflect adequate aggregation of progress from sub-national levels. This research focuses on assessing the progress of SFDRR implementation at sub-national levels in Aceh province, Indonesia – the place where Indian Ocean Tsunamis killed around 170,000 people on Boxing Day 2004. The authors combined key informant interviews and content analysis of policy documents to collect evidence of the progress in the four SFDRR priorities for action. Two case villages in Aceh demonstrated challenges and opportunities at local levels. Findings suggest gaps in SFDRR implementation include a lack of deliberation of risk assessment and knowledge dissemination, discontinuity of regional DRR forums, lack of incentives for mitigation and shared commitments, and responsibility. Progress at village levels is equally challenging due to the lack of funding allocation, discontinuity of village-level preparedness, and lack of adoption of sustainable recovery and community participation. In summary, since the progress of implementing DRR across four priority areas of the SFDRR in Aceh is not optimal, Aceh authorities (e.g. provincial and district secretariats), provincial and district Disaster Management (DM) Agencies, and other relevant DM actors need to comprehensively improve DRR across all four Priorities for Action of the framework in the province.

Integration of disaster risk reductionand climate change adaptation in Aceh: Progress and challenges after 20 Years of Indian Ocean Tsunamis

The Indian Ocean Tsunami (IOT) of 2004, which tragically claimed 168,000 lives and displaced about half a million people in the Aceh region of Indonesia, established Aceh's reputation as one of the most geologically volatile areas in Southeast Asia. Unfortunately, the 2004 IOT also altered some geomorphological changes, particularly land subsidence in the coastal areas of South, Southwest, and West Aceh, making these regions more susceptible to coastal floods and inundation over the last 20 years. The 2004 tsunamigenic earthquakes had been compounded by hydroclimatic hazards (and required to reduce risk beyond geological disasters) that continued to cause loss and damage, compromise communities' well-being, and reproduce vulnerabilities. This article examines the progress and challenges for integrating disaster risk reduction (DRR) and climate change adaptation (CCA) in Aceh, with a focus on the capital city, Banda Aceh using in-depth stakeholder interviews and document reviews. Anticipating gaps in meeting Sendai Framework 2030 target, as also observed elsewhere in Indonesia and Southeast Asia, the findings suggest various key challenges for the integration, including (1) fragmented DRR and CCA policies leading shaped the gap in coordination and collaboration among actors; (2) nurturing political commitment remains a challenge at local level; (3) lack of fiscal capacity and lack of earmarked allocation hampers the potential integration; (4) and deficits in community participation delayed adaptation and integration. The study offers recommendations for policy insights and consideration.

Computational Modelling of 2004 Off West Coast of Sumatra Earthquake-Tsunami Wave Propagation Using Two-Dimensional Cellular Automata in the Eastern Indian Coast

ABSTRACT The ability to detect destructive tsunamis and spare lives from serious harm has made the computation of tsunami wave dynamics increasingly important. The tremendous loss of life and property brought on by the 26th of December, 2004 tsunami has raised the demand for accurate and timely propagation of tsunami wave simulations. These days, a variety of early warning technologies and models are utilized to predict tsunami waves. The propagation phase of a tsunami wave is simulated using two-dimensional cellular automata of rectangular lattices in eight directions from this research. Modelling of the Sumatra-Andaman earthquake in 2004 to simulate the propagation of tsunami waves to strike the northern coasts of India. The earliest tsunami arrival time, travel time, and wave spread rate are determined from this study, and the results are verified using historical data.

Analysis of TEC variations and prediction of TEC by RNN during Indonesian earthquakes occurred from 2004 to 2024 and comparison with IRI-2020 model

The Ionosphere, a crucial region of Earth’s atmosphere extending from approximately 50 to 1000 km above the Earth’s surface, plays a pivotal role in global communication, navigation, and satellite-based technologies. Among its various parameters, Total Electron Content (TEC) stands out as a key metric, representing the integrated electron density along a specific path through the ionosphere. This research focuses on analyzing TEC variations during Indonesian earthquakes between 2004 and 2024 using a Recurrent Neural Network (RNN) model. The study investigates the ionospheric response to seismic activity, particularly in Indonesia, a region prone to earthquakes due to its location within the Pacific Ring of Fire and complex tectonic setting involving multiple lithospheric plates. The RNN model, designed to predict TEC variations during earthquakes, utilizes data on solar and geomagnetic activity, including the Kp index, solar wind, and geomagnetic storm activity, obtained from the OMNIWEB data centre, along with TEC data from the IONOLAB data servers for the BAKO station in Cibinong, Indonesia. The earthquakes considered for observation include significant events such as the 2004 Indian Ocean earthquake and tsunami, the 2012 Wharton Basin earthquake, and subsequent seismic events up to 2024. Statistical metrics such as Mean Bias Deviation (MBD), Relative Error (REL_E), Absolute Error (ABS_E), and Root Mean Square Error (RMSE) are used to evaluate the predictive capability of the RNN model and compare it with the International Reference Ionosphere (IRI) 2020 model, a widely accepted empirical model for describing ionospheric parameters. The comparison reveals the performance of the RNN model in capturing TEC variations during seismic events, providing valuable insights for earthquake monitoring and early warning systems.

Diasporas as a linchpin in local and international humanitarian action: a case study of the Chinese in Aceh following the 2004 tsunami.

Chinese humanitarian actors have worked frequently with the Chinese diaspora in disaster-affected areas, but little, if any, research has been conducted into the important role of the diaspora in disaster response and humanitarian assistance. This paper investigates what local knowledge the Chinese diaspora has offered to humanitarian actors from the People's Republic of China (PRC), and how this has contributed to their effectiveness. Based on a case study of the semi-autonomous Indonesian province of Aceh in the aftermath of the Indian Ocean tsunami of 2004, this paper argues that the diaspora can serve as a linchpin in local and international humanitarian action. It can do so by strengthening networks and bringing together local ethnic communities, local governments, and the PRC's humanitarian actors, while also offering local knowledge in the form of contextual memory. Such local knowledge may have to be fully utilised to address any underlying ethnic tensions in disaster-affected areas.

Indicative microzonation map of the contact zone between the kenny hill and limestone formation using active, passive and hybrid MASW methods

Abstract The impact of the far-field earthquake generated by the Sumatra-Andaman earthquake (Richter scale of 9.3) was also felt by Malaysians. The ground motion triggered by this earthquake is caused by the shear wave velocity (Vs), particularly at a depth of 30 m (Vs30). Therefore, this dynamic soil properties need to be determined, which was evaluated using the active, passive, and hybrid multichannel analysis of surface waves (MASW) methods at 16 locations in the contact zone between the Kenny Hill and limestone formations in Kuala Lumpur, Malaysia. The Vs determined from the MASW for the contact zone ranging from 198 m/s to 286 m/s at the ground surface and from 376 m/s to 662 m/s at 30 m depth. In contrast, in the non-contact zone, Vs range from 212 m/s to 328 m/s at the ground surface and from 562 m/s to 921 m/s at 30 m depth. For Vs30, the contact zone has a minimum value of 280 m/s and a maximum value of 380 m/s, while the non-contact zone has a minimum value of 370 m/s and a maximum value of 530 m/s.

Qualitative Geochemical Analysis of the 2004 Indian Ocean Giant Tsunami Deposits Excavated at Seungko Mulat Located in Aceh Besar of Indonesia Using Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) was employed to characterize the geochemical signatures layer by layer of 2004 Indian Ocean tsunami deposits in Seungko Mulat Village, Aceh Province, Indonesia. In the LIBS experimental setup, a Nd-YAG laser beam is directed towards the deposit samples, and the resulting atomic emission lines from the laser-induced plasma are captured using a spectrometer. Our analysis reveals terrestrial indicators (Fe), heavy metals (Cu, Cr, Co, Cd), and increased emission intensity of Mg, Ca, Al, K, Si, Ba, N, and O in the 2004 Indian Ocean tsunami layers. The emission intensity ratios of several elements in the 2004 Indian Ocean tsunami deposit layers, namely Ca/Ti, Si/Ti, and K/Ti, unveil notable disparities among the elements evaluated. This indicates the possibility of utilizing these ratios as reliable geochemical markers to differentiate the layer by layer of tsunami deposits. LIBS surpasses XRF in detecting nearly all elements simultaneously and identifying both light elements and specific heavy metals (Ba, Cu, Cr, Co, Cd, Pb, Ni, V, W), exceeding XRF's detection capabilities. This study emphasizes the effectiveness of LIBS as an advanced optical technique, offering speed and promise in analyzing layer-by-layer geochemical markers of the 2004 Indian Ocean tsunami deposits in Seungko Mulat Village.

Some results from a transversely excited atmospheric carbon dioxide-laser induced breakdown spectroscopy investigation of tsunami deposit cored from Aceh Besar coastal region

Abstract We undertook an extensive analysis to examine the geochemical imprints encapsulated within the samples of the 2004 Indian Ocean tsunami deposits procured from the Seungko Mulat coastal region, nestled in the western section of Aceh Besar Regency, Aceh Province, Indonesia. In order to induce the formation of micro-plasma, a Transversely Excited Atmospheric Carbon Dioxide-Laser Induced Breakdown Spectroscopy (TEA CO2-LIBS) has been employed as the excitation source. Our investigation unveils distinct spectral signatures within every layer of the stratified tsunami deposit. We observed the unmistakable presence of salt elements (Ca, K, Mg, Na, Al), transition metals, heavy metals (Si, Fe, Ti, Ba, Sr, Cu, Cr, Pb, Mn, Ni, V), and also organic constituents (C, H, O, and N). The emission intensities of these elements exhibited a significant increase within the layers of the tsunami deposit, unequivocally setting them apart from their non-tsunami equivalents. In addition, we performed a vertical analysis of LIBS elemental emission intensity ratios, unveiling unique values for the Ca/Ti, and Si/Ti, ratios, which significantly distinguish them from all other ratios scrutinized in this exhaustive investigation. This research serves to highlight the effectiveness of TEA-LIBS as a promising and efficient optical technique for discerning the chemical profile associated with the renowned 2004 Indian Ocean tsunami deposits from Seungko Mulat Village in Aceh Province.

Mangrove vegetation response to alteration in coastal geomorphology after an earthquake in Andaman Islands, India

The 2004 Sumatra-Andaman earthquake caused a devastating tsunami and shifts in land elevations, which had an instantaneous as well as the long-term impact on the Andaman Islands. Especially, the coastal uplift and subsidence has altered the tidal regime, leading to mass mortality and degradation of mangroves (∼150 sq. km). The tectonic shift in the Andaman archipelago has created three broader geographical units: North Andaman with coastal uplift (∼1.3 m) – sea level drop (SLD) scenario; Middle Andaman with minor to no change in coastal geomorphology – no change scenario; and South Andaman with coastal subsidence (∼1.1 m) – sea level rise (SLR) scenario. How these changes in the tidal regime have influenced mangrove vegetation remains less understood. Therefore, we assessed mangrove vegetation characteristics across the Andaman Islands to examine mangrove response to coastal uplift and subsidence after 18 years since the disturbance. The uplifted sites mimicking the SLD scenario appeared more destructive to mangroves (tree density - 771/ha) in comparison to subsided sites mimicking the SLR scenario (tree density - 937/ha), while no change sites with the highest tree density (1288/ha) showed lowest impacts to mangrove. The species diversity (H’=Shannon-Wiener index) within recruitment cohorts (seedlings: <1 cm DBH and saplings: ≥1 cm and <5 cm DBH) sapling (H’=1.57), and seedling (H’=1.48) was significantly higher than the trees (H’=1.20). Rhizophora apiculata and Ceriops tagal were the dominant species (cumulative IVI 60%) found in survived mangrove forests demonstrating their high resilience for sudden changes in tidal regime. Our study provided a comprehensive account of mangrove vegetation response after a major disruptive event in 2004. Long-term monitoring of these novel sites would enhance our understanding of mangrove response to sea level change, which can also provide significant insights for the restoration and management of mangroves.

Tsunami Runup Attenuation By Onshore Obstacles

In a time of climate emergency due to global warming, nature-based coastal defence systems are attractive solutions for flood mitigation and adaptation. Coastal forests such as mangroves have received a growing interest for their disaster mitigation effectiveness such as water flow energy dissipation, hence helping communities to become more resilient (Iimura &amp; Tanaka, 2012). The role of coastal forests as a defence measure was highlighted in the aftermath of the 2004 Indian Ocean Tsunami, which claimed the lives of more than 200,000 people and displaced millions more across fourteen countries. Post-disaster damage observations indicated that forests, particularly mangroves, reduced the impact of the tsunami wave in some locations. As a result, significant international relief and reconstruction efforts focused on extensive forest replantation of coastlines (Satake, 2014). The role of coastal vegetation in reducing the severity of tsunami waves has been studied since. Several studies using physical modelling and computational approaches have provided insights into the wave attenuation provided by coastal vegetation, in terms of relationships between incident hydrodynamic conditions, forest configurations and wave height decay. However, there are still many gaps in knowledge, particularly in quantifying the efficacy of coastal forests in reducing inland hydrodynamic conditions (Tomiczek et al., 2020). It is therefore essential to improve the understanding on how wave heights, velocities and runup are influenced by the characteristics of the “obstacles”, e.g. the forest density, as well as the incident hydrodynamic conditions, e.g. the wave period. This study aims to address these questions conducting physical experiments using the novel pneumatic Tsunami Simulator (TS) developed by HR Wallingford together with UCL (Rossetto et al., 2011).

A Study of Implementation of Special Autonomy Law: An Evidence from Post Peace Conflict of Aceh, Indonesia

After the Tsunami in Aceh, the conflict between the Free Aceh Movement (GAM) and the Government of Indonesia, which had persisted for over three decades, was resolved. This resolution was achieved when both parties agreed to implement asymmetric decentralization or special autonomy in Aceh. The implementation of Special Autonomy is governed by Law Number 11 of 2006 concerning the Government of Aceh, specifically regarding the use of the Flag and Emblem for Aceh. This study investigates the factors contributing to the divergence in opinions between the Central Government and the Government of Aceh concerning Qanun No. 3 of 2013 regarding the Aceh Flag and Coat of Arms. This research employed a qualitative approach and conducted in-depth interviews with 15 participants. The findings revealed that the conflict between the Central Government and the Aceh Government regarding the Aceh Flag and Coat of Arms stems from differing perceptions and interpretations of the Crescent Star flag and Bouraq-Lion symbol, which bear resemblance to the flag and logo used by the Aceh Movement. Merdeka (GAM) and Government Regulation Number 77 of 2007 concerning Regional Emblems. Conflict resolution has reached an impasse, as both parties involved maintain their respective positions. This deadlock resulted in the unauthorized display of the crescent and star flag by Acehnese citizens, a decline in Acehnese support for the Aceh Party, and the strengthening of potential regional disintegration in Aceh. This study suggests that the implementation of special autonomy as part of the consensus on conflict resolution may be compromised if the previous agreement is not upheld.

City of prone natural disasters: Mitigating post-tsunami on the coastal of Banda Aceh, Indonesia

This research investigates the mitigation strategies employed in Banda Aceh, Indonesia, following the devastating 2004 Indian Ocean tsunami. Aimed at understanding how the city, prone to natural disasters, has enhanced its resilience and recovery capabilities, the study meticulously evaluates the implementation of various mitigation measures ranging from ecosystem-based coastal protections to advanced early warning systems, community education, and infrastructural resilience. Utilizing a qualitative methodology, including surveys with high Cronbach's Alpha values indicating strong reliability and consistency, the research delves into the effectiveness of these strategies. It also considers the roles of various stakeholders, including local communities, government agencies, and international partners, in fostering a collaborative disaster recovery effort. The findings highlight the critical importance of community engagement and the integration of local knowledge into disaster management practices. Furthermore, the study underscores the necessity of continuous improvement in disaster management strategies to cope with the evolving nature of natural threats. By comprehensively analyzing Banda Aceh's post-tsunami mitigation efforts, this research offers valuable insights for other regions globally vulnerable to natural disasters, emphasizing the importance of preparedness, community resilience, and sustainable recovery strategies.

Tolerance of Tourists in Praying in the Prayer Well Room of the Aceh Tsunami Museum

Indonesia is a maritime country located between three world plates that move together, so Indonesia is a country that has a high earthquake rate. Earthquakes that occur at sea can cause giant waves (tsunami). One of the tsunamis that occurred in Indonesia was the Aceh tsunami in 2004. To commemorate this incident, the Aceh Tsunami Museum was built. This museum was built on December 26 2009, so that the victims of the Tsunami disaster would not be forgotten, then as a safety education center, and an evacuation center if another Tsunami occurred. Inside the Tsunami Museum there is a room called the wishing well. On the walls of the prayer well room are the names of the victims of the Aceh Tsunami. Every visitor who enters here is encouraged to pray for the victims according to their respective beliefs. This is where we can see religious tolerance. The formulation of the research problem is how is the tolerance of tourists in praying in the space of sorrow (praying well room) of the Aceh Tsunami Museum? This research aims to determine the tolerance of tourists in praying in the space of sorrow (praying well room) of the Aceh tsunami museum. The method in this research is a qualitative approach where interviews and observations are carried out. The results obtained from the field will be analyzed and described in detail by researchers. The results of this research are that every visitor has a high level of tolerance

Tsunami Geotourism Potential in Aceh and Regional Government Efforts and Constraints in its Development

The 2004 earthquake and tsunami left geological heritage sites and tsunami impact sites as disaster mitigation education through tsunami geotourism. The aim of the research is to identify the potential for developing tsunami geotourism in Aceh and analyze the efforts and constraints of the Regional Government through technical institutions in charge of developing tsunami geotourism in Aceh. The research used a descriptive qualitative method by interviewing sources from the Aceh Energy and Mineral Resources Service, Aceh Disaster Management Agency, Aceh Tourism Office, UPT. Aceh Tsunami Museum and UPT. Syiah Kuala University Disaster Mitigation, as well as observing several geological heritage sites and tsunami impact sites in Aceh based on the results of interviews and literature studies. The research results show that Aceh has the potential to develop tsunami geotourism with many tsunami heritage objects including Ek Leuntie Cave, Zero Tsunami Hill Lhoknga, Tsunami Museum, PLTD Floating Ship, Ship on the roof of the house, Aceh Monument Thanks the world, Gurah Mosque Dome, Baiturrahim Mosque, Rahmatullah Mosque, high tsunami monument and mass grave. In conclusion, Aceh has the potential to develop tsunami Geotourism and the Aceh Government has managed tsunami sites for tourism and proposed several geological heritage sites in Aceh to be designated as Geosites, but is hampered by, among other things, the Aceh Government's minimal budget, lack of coordination between technical institutions and difficulties in land acquisition

Humanitarian Logistics and Emergency Response in Humanitarian Organizations in Kenya.

Disasters were unpredictable and unavoidable, necessitating adequate disaster response plans. Humanitarian logistics, which gained prominence after the 2004 Asian tsunami, played an important part in crisis prevention. Despite weak links in relief chain management, issues remained. Humanitarian logistics had a huge impact on disaster relief efforts, as studies revealed a variety of challenges, including a lack of sufficient SCM software and poor facilities. Despite its importance, few studies have explored the impact of disaster assistance on humanitarian organizations, particularly in Kenya. The study sought to address this gap by evaluating the impact of humanitarian logistics on emergency response in Nairobi, Kenya. Humanitarian groups, policymakers, and NGOs profited from the research, which informed strategic planning and policy creation to strengthen disaster response operations. The Resource Dependency Theory (RDT) proposed that organizations rely on external resources for survival and growth. It underlined the importance of forming strategic alliances to secure resources. In humanitarian settings, logistics were critical in procuring and allocating resources for successful emergency response. The research methodology used a cross-sectional descriptive design to investigate the association between humanitarian logistics management techniques and emergency response in Kenyan humanitarian organizations. Semi-structured questionnaires were used to obtain data from 64 Nairobi-based firms. Data analysis required the use of both descriptive and inferential statistical techniques, such as regression and correlation analysis. The study found a significant positive association (β = 0.732, p &lt; 0.001) between logistics management practices and emergency response, indicating that improving logistics leads to better response outcomes. The study recommended prioritizing logistical development and resource allocation to improve emergency response capabilities.

Latitudinal variation in seagrass communities with special emphasis on post-tsunami status in the Andaman and Nicobar archipelago, India.

We studied spatial variation in seagrass communities in the Andaman and Nicobar archipelago (ANI), India using latitude as a surrogate variable. We classified the ANI into five latitudinally distinct island groups: North & Middle Andaman, Ritchie's archipelago, South Andaman, Little Andaman, and the Nicobar archipelago. We evaluated the Importance Value Index (IVI) for species to determine the ecologically dominant seagrasses within each Island group. Later, we related our findings to investigate the three decadal pre- and post-tsunami status of seagrass habitats in the ANI which were severely impacted by the Indian Ocean tsunami of 2004. Six of the 11 observed species, such as Halophila ovalis, Halophila beccarii, Halophila minor, Halodule pinifolia, Thalassia hemprichii, and Cymodocea rotundata, dominated the seagrass population among all island groups. Seagrass composition significantly varied across the five investigated latitudinal gradients. Seagrass communities in 'Ritchie's Archipelago and Nicobar' and 'South Andaman and Little Andaman' revealed the highest and lowest variation. Further, Ritchie's Archipelago and Nicobar had the highest species richness (n = 10), followed by North & Middle Andaman (n = 8), and the lowest in South and Little Andaman (n = 6). Despite similar species richness and composition, Nicobar contributed to the highest seagrass coverage compared to the lowest recorded in the Ritchie's Archipelago. Our observations on the re-colonization of disturbed areas by early successional and historical species suggest recovery of the seagrass population in the ANI post-disturbance. Lastly, co-variates associated with latitude as a surrogate warrant further investigation.

Evolution of trends in Sri Lankan mangrove research and future prospects

The trend of sporadic surveys and qualitative descriptions of Sri Lankan mangrove flora in the first half of the 20th century has gradually changed to include quantitative studies on floristics, nevertheless, studies on quantification of fauna associated closely with mangrove ecosystems are scarce. Microbial diversity, especially in soil, and its ‘contribution to the detritus cycle are the least studied. The tendency to engage in short-term research at convenient sites affects the quality and relevance of research output with some redundancy, resulting in a marginal contribution to the knowledge base on mangrove ecology. Studying mangrove ecosystem functions/ services demands long-term collection of data that would have made them less attractive research ventures. Research on trophic relationships, detritus and nutrient cycling, habitat and pollination functions too have had the same fate. The Indian Ocean tsunami in 2004 triggered a considerable interest in the coastal protection function of mangroves, as it was evident that mangroves and other coastal vegetation provided superior resistance to tsunami waves than hard engineering coastal protective structures. This has led to an unprecedented trend of mangrove afforestation for coastal defense, more than to research on planting techniques and maintenance to enhance the survival and growth of seedlings. This is still an under-researched aspect. Escalating recognition of blue carbon as a climate-smart solution and the development of market mechanisms for blue carbon trading have induced a considerable research interest in quantifying the mangrove blue carbon stocks, especially in the soil. Research on atmospheric carbon removal capacity/rates of mangrove plants/forests through photosynthesis however, lags behind for the reason that it requires data collection for a longer period that demands greater financial and labour investment. The urgency created by the current climate change crisis for effective solutions to reduce atmospheric greenhouse gases may provide a conducive environment for mangrove research.

Examining the Factors Influencing Tsunami Evacuation Action Selection in Thailand: A Comprehensive Study Involving Local Residents, Non-Local Workers, and Travelers

Tsunamis are a substantial natural threat in Thailand, as evidenced by the 2004 Indian Ocean tsunami. Effective evacuation is vital to reduce casualties and property damage. However, despite improved warning systems, high death tolls still occur, indicating complex evacuation behavior influenced by various factors. This study examines these factors among diverse groups in Phuket and Phang Nga, Thailand. A survey of 1000 locals, non-local workers, and travelers assesses threat and coping appraisals, past tsunami experiences, gender, age, and tsunami evacuation intention and action selection. Partial Least Squares Structural Equation Modeling (PLS-SEM) was used to analyze the data based on the hypotheses related to the Protection Motivation Theory (PMT). The results of the analyses show that threat and coping appraisals significantly predict tsunami evacuation intention, and gender influences threat perception related to evacuation. Variations among respondent types emphasize the need for tailored disaster preparedness and response strategies. This study offers crucial insights for policymakers, emergency responders, and disaster management stakeholders, underlining the significance of further research into the intricate interplay of individual and contextual factors shaping tsunami evacuation behavior.

Identification ratio of Si/Ti and Ca/Ti content by X-Ray Fluorescence in tsunami soil samples

Earthquakes and tsunamis natural disasters have repeatedly occurred on the coast of Aceh province, which lies between the confluence of two plates. The tsunami deposits in this area can provide important information regarding the reconstruction of marine attacks by past earthquakes and tsunamis. In general, tsunami deposits can be identified based on their geological, sedimentological, paleontological, and geochemical characteristics. In our research work, spectrometry X-ray fluorescence (XRF) has been utilized to investigate the geochemical signatures of tsunami-affected soil samples in Aceh province at three tsunami-impacted areas, namely Aceh Besar regency, Banda Aceh City, and Aceh Barat regency. The sampling point is located about a kilometer from the coastal line. Our findings indicate that tsunami-affected soils in Aceh Province after 10 years struck by tsunami contain terrestrial markers such as Fe and Ti, carbonate markers (Mg, Ca), and heavy metals elements (Cr, Ni, Cu, Zn, and Sr). On the other hand, in our study, the concentration ratios of several elements such as Si/Ti and Ca/Ti seem most suitable as a chemical signature for differentiating environmental conditions such as the 2004 Indian Ocean tsunami event. It could be noticed that geochemical analysis by XRF can be applied to characterize the tsunami-affected soils in several coastal areas of Aceh province.