Coastal Vulnerability Index Research Articles

Coastal Vulnerability Assessment of Bali Province, Indonesia Using Remote Sensing and GIS Approaches

Coastal zones are considered to be highly vulnerable to the effects of climate change, such as erosion, flooding, and storms, including sea level rise (SLR). The effects of rising sea levels endanger several nations, including Indonesia, and it potentially affects the coastal population and natural environment. Quantification is needed to determine the degree of vulnerability experienced by a coast since measuring vulnerability is a fundamental phase towards effective risk reduction. Therefore, the main objective of this research is to identify how vulnerable the coastal zone of Bali Province by develop a Coastal Vulnerability Index (CVI) of areas exposed to the sea-level rise on regional scales using remote sensing and Geographic Information System (GIS) approaches. This study was conducted in Bali Province, Indonesia, which has a beach length of ~640 km, and six parameters were considered in the creation to measure the degree of coastal vulnerability by CVI: geomorphology, shoreline change rate, coastal elevation, sea-level change rate, tidal range, and significant wave height. The different vulnerability parameters were assigned ranks ranging from 1 to 5, with 1 indicating the lowest and 5 indicating the highest vulnerabilities. The study revealed that about 138 km (22%) of the mapped shoreline is classified as being at very high vulnerability and 164 km (26%) of shoreline is at high vulnerability. Of remaining shoreline, 168 km (26%) and 169 km (26%) are at moderate and low risk of coastal vulnerability, respectively. This study outcomes can provide an updated vulnerability map and valuable information for the Bali Province coast, aimed at increasing awareness among decision-makers and related stakeholders for development in mitigation and adaptation strategies. Additionally, the result may be utilized as basic data to build and implement appropriate coastal zone management.

Exploring the Impact of Tropical Cyclones on Oman’s Maritime Cultural Heritage Through the Lens of Al-Baleed, Salalah (Dhofar Governorate)

Tropical cyclones are among the most detrimental hazards to the environment, societies, and economies, each year affecting millions of people and resulting in substantial casualties and material destructions in coastal communities. In this context, maritime cultural heritage, encompassing material evidence for the engagement of people with the sea, both on land and under water, is particularly vulnerable. Despite the significant number of archaeological sites exposed to tropical cyclones and other extreme sea-level events, maritime cultural heritage in the MENA region is rarely included in coastal vulnerability indices or incorporated in mitigation strategies, disaster management, sustainability, and resilience policies. In this study we examine the impact of tropical cyclones on the maritime archaeology of Oman with emphasis on the Dhofar region. This paper builds on existing coastal research in the Dhofar region—an area identified as the most cyclone-prone administrative region in Oman, but also an area that contains substantial archaeological remains. Central among Dhofar’s maritime cultural heritage is Al-Baleed, a Medieval seaport with unparalleled evidence of engagement with international trade networks.

Impacts of sea-level rise on coastal zones of Mauritius: insights following calculation of a coastal vulnerability index

Impacts of sea-level rise on coastal zones of Mauritius: insights following calculation of a coastal vulnerability index

Integrated socio-environmental vulnerability assessment of coastal hazards using data-driven and multi-criteria analysis approaches

Coastal hazard vulnerability assessment has been centered around the multi-variate analysis of geo-physical and hydroclimate data. The representation of coupled socio-environmental factors has often been ignored in vulnerability assessment. This study develops an integrated socio-environmental Coastal Vulnerability Index (CVI), which simultaneously combines information from five vulnerability groups: biophysical, hydroclimate, socio-economic, ecological, and shoreline. Using the Multi-Criteria Decision Making (MCDM) approach, two CVI (CVI-50 and CVI-90) have been developed based on average and extreme conditions of the factors. Each CVI is then compared to a data-driven CVI, which is formed based on Probabilistic Principal Component Analysis (PPCA). Both MCDM and PPCA have been tied into geospatial analysis to assess the natural hazard vulnerability of six coastal counties in South Carolina. Despite traditional MCDM-based vulnerability assessments, where the final index is estimated based on subjective weighting methods or equal weights, this study employs an entropy weighting technique to reduce the individuals’ biases in weight assignment. Considering the multivariate nature of the coastal vulnerability, the validation results show both CVI-90 and PPCA preserve the vulnerability results from biophysical and socio-economic factors reasonably, while the CVI-50 methods underestimate the biophysical vulnerability of coastal hazards. Sensitivity analysis of CVIs shows that Charleston County is more sensitive to socio-economic factors, whereas in Horry County the physical factors contribute to a higher degree of vulnerability. Findings from this study suggest that the PPCA technique facilitates the high-dimensional vulnerability assessment, while the MCDM approach accounts more for decision-makers' opinions.

Coastal vulnerability analysis and RIDIT scoring of socio-economic vulnerability indicators – A case of Jagatsinghpur, Odisha

The study focuses on interpreting climate-induced disaster vulnerability in quantifiable form, caused by tropical cyclones emerging in the Bay of Bengal along the Eastern coast of India. The case of Jagatsinghpur, one of the six coastal districts of the Indian state of Odisha, has been explored for this purpose at a sub-regional level. An inclusive methodology comprising observation, structured questionnaire surveys, and documentation of past occurrences of cyclonic storms was adopted for the research. The selection of indicators was made at both regional and sub-regional (rural) levels. A two-step analysis was done using Coastal Vulnerability Index Model and RIDIT scoring to evaluate the vulnerability along the Jagatsinghpur coastline, and rank socio-economic vulnerability indicators based on the perception of local inhabitants of the selected Tarasahi village. The coast of Jagatsinghpur is not a stable one and is undergoing fast rates of erosion and accretion, with variation in vulnerability levels at different points along the coastline. By analyzing past disaster management trends and existing conditions, the research outcome provides valuable information that can support future disaster management and risk reduction policies, spanning both proactive and reactive approaches.

GIS based coastal vulnerability assessment and adaptation barriers to coastal regulations in Dakshina Kannada district, India

Coastal areas represent fragile and complex ecosystems. Changes in climate, increasing urbanization and industrialization are creating immense pressure on the coastal environment. Coastal erosion, sea level rise, changing morphology of the coastal areas and extreme weather events are some of the threats that coastal regions are experiencing globally. While various studies have assessed the vulnerability of coastal regions quantitatively and spatially, there is a need to supplement these findings with qualitative insights based on human experiences. Thus, the present study carried out a coastal vulnerability assessment along the coastline of Dakshina Kannada district in Karnataka, India using Shannon’s Entropy by including eight parameters i.e., slope, elevation, geomorphology, bathymetry, sea level rise, mean tidal range, mean significant wave height and shoreline change. The study also explored the experiences and perceptions of stakeholders regarding adaptation barriers to climate change vulnerabilities for understanding the ground complexities. Coastal vulnerability index (CVI) revealed that nearly 39.7 km of the coastline is vulnerable including areas along Sasihtlu beach, Munda, New Mangalore Port Batapady beach, Uchilla, Kotekar, Ullal beach, Netravati River Area and Mukka beach. Rainfall induced coastal erosion, lack of coordination among the various stakeholders, policy makers and practitioners regarding a common framework for climate change adaptation strategies were identified adaptation barriers. The findings of CVI and adaptation barriers may be used by practitioners and policy makers for framing the adaptation measures for mitigating the implications of the coastal region.

Coastal Vulnerability Assessment: A case study of the Ratnagiri coast, Maharashtra, India

The coastal zone is a vulnerable habitat that needs extra caution to protect ecosystems. Coastal systems are increasingly threatened by possible climate change consequences, as evidenced by the Intergovernmental Panel on Climate Change’s consecutive assessments. Increased tropical storm occurrences in recent years, in addition to the devastation caused by the tsunami in December 2004, have highlighted the necessity of analyzing the coast’s susceptibility to flooding-induced hazards to get a better knowledge of the factors that generate various hazards and, as a result, reduce the after-effects of future occurrences. The Ratnagiri coast in Maharashtra is prone to erosional hazards, periodic land rehabilitation, and sudden rises in sea level. The main objective is to calculate the CVI (Coastal Vulnerability Index) for the Ratnagiri coast. To analyze the vulnerability of the coastal region, eight risk parameters were used, viz. shoreline change rate, coastal elevation, sea level change rate, coastal slope, tide range, significant wave height, coastal geomorphology, and tsunami arrival height. The coastal vulnerability map was created by categorizing the numerous coastal portions into three vulnerability groups: high, medium, and low, which will aid coastal residents in risk mitigation in the future.

Coastal vulnerability assessment of India's Purba Medinipur-Balasore coastal stretch: A comparative study using empirical models

The 90.20 km coastal stretch extending from India's Subarnarekha estuary (Balasore District, Odisha) to the mouth of the Haldi River (Purba Medinipur, West Bengal) was evaluated. The evaluation was for vulnerability to climate extremes and variabilities (e.g. tropical cyclones, storm surges, and eustatic sea-level rise) resulting in coastal erosion, inundation, salinization and increased biophysical and socio-economic impacts. Coastal vulnerability mapping with respect to coastal hazards was applied to identify and implement risk reduction policies. In order to understand the spatial distribution of physical vulnerability along this coastal stretch, the Coastal Vulnerability Index (CVI) using Gornitz's CVI model and the Analytical Hierarchy Process (AHP) method were applied. These models were run in ArcGIS ver. 10.5 using six geological parameters viz., elevation, slope, bathymetry, coastal geomorphology, shoreline change, and coastal land use and four physical process variables viz. Mean sea level (MSL), mean tidal range, significant wave height, and storm surge height. Both of the models produced very good results. Based on Gornitz's CVI model, it was found that 13.56% of the coastline is highly vulnerable to these hazards, while the AHP model indicated 11.29% of the coast was at high vulnerability. When both models were simulated the same probable inundation extent of two different storm surge scenarios of wave height, viz. ≤ 3 m and≤5 m, the areas estimated to be affected by the surge were 255.22 and 779.59 sq. km, respectively. The coastal blocks of Nandigram-I, Contai-I, Deshopran, and Bhograi were identified as highly vulnerable due to landward erosion and inundation. The study inferred that the combined effect of cyclonic activities and storm surge along with high tide made the coast highly susceptible. This study could help coastal planners, decision-makers, and administrators to prepare a risk management plan for long-term coastal conservation and management.

Multi-hazard risk assessment of coastal municipalities of Oaxaca, Southwestern Mexico: An index based remote sensing and geospatial technique

Multi-hazard risk assessment (MHRA) modelling was done for the coastal region of Oaxaca in the south-western coast of Mexico that is vulnerable to diverse high-risk multiple natural hazards. The study aimed to evaluate the MHRA of Oaxaca by combining both vulnerability and hazard variables using various indices. The Integrated Coastal Vulnerability Index (ICVI) was calculated by combining multiple sub-index parameters such as Coastal Characteristics (CCSI), Coastal Forcing (CFSI) and Socio-economic factors (SESI). CCSI results indicated that around 20.6% of the coastal municipalities are in a very high vulnerability category that covers the north-western and south-eastern region of Oaxaca, while CFSI indicated 13.45% of the area as very high vulnerability due to the increased impacts of cyclone density and rainfall distribution in the mountainous region. The ICVI indicated that the percentage of area in each class was represented as very low (15.43), low (28.96), moderate (31.67), high (17.11) and very high (6.83). The multi-hazard assessment of inundation scenarios showed that 48.28% of Heroica Ciudad de Juchitán de Zaragoza is under the class of high-very high vulnerability. MHRA map provided a detailed description of population and household exposure at different risk categories, where 70–98% of population and household are categorized as high-very high risk in San Mateo del Mar, San Francisco del Mar and Salina Cruz municipalities. Hence, this type of study could be applied for different regions around the world for integrating mitigation plans in the reduction of the potential impacts of multiple coastal hazards.

Comparison of coastal vulnerability assessment for Subang Regency in North Coast West Java-Indonesia

Coastal vulnerability is a spatial concept that can contributes to decision-making processes in managing the coast. Our study aims to compare and evaluate the coastal vulnerability index (CVI) and the weighted CVI (CVIw) along the Subang Regency coastline in northern part of Java Island-Indonesia. We use coastal parameters: coastal relief, morphology, shoreline change, tidal range, sea-level change, wave height, land subsidence, and land use. Then, vulnerability maps are prepared to highlight areas with low, medium, high, and very high vulnerability. The vulnerability parameters map showed that shoreline change, land subsidence, and land use are influencing the vulnerability more than other parameters. The CVIw appears to be more favourable to assess the Subang Coast vulnerability, in which the very high vulnerability (43%) is dominant compared to the CVI (21%). This will require urgent protective action from the coast managers. Both CVI and CVIw have a 21% of very high risk in the same areas (Mayangan, Legon Wetan, and Pangarengan Villages), and these areas need protection from the coastal land loss. Meanwhile, the authority has plans for aquaculture in the area, and we suggest that it should be planned thoroughly to ensure that the practice does not destruct the coasts any further.

Coastal vulnerability index as a tool for current state assessment and anthropogenic activity planning for the Eastern Gulf of Finland coastal zone (the Baltic Sea)

Coastal reclamation is a major feature of contemporary land planning. As a multicomponent natural system, the coastal zone is impacted by various external processes (inundation, erosion, etc.) and land habitat demands an increased focus on anthropogenic activity. For the first time, a coastal vulnerability index (CVI) has been determined for the easternmost area of the Gulf of Finland (the Baltic Sea) (EGoF) in order to assess vulnerability of the coastal zone to erosion. The parameters for the CVI assessment were identified on the basis of existing field observations and analysis of environmental factors expressed in the EGoF. This research is focused on coastal segments prone to the rapid development of erosion, a subject highly relevant for coastal management. The CVI assessment, based on a method proposed by Gornitz (1991), uses seven physical parameters grouped according to geological, geomorphological, lithodynamic and hydrodynamic characteristics. Storminess, or susceptibility to destructive storm events, was applied for the study area not only because of the global increase in storm activity but also because this area undergoes a “bay-effect”. An experts’ assessment distinguished the most crucial parameters that triggered the coastal erosion process, namely that coastal geology and the number of destructive storms affected coastal processes.

Coastal Vulnerability Assessment for Community Resilience on Abrasion: Case of Bugel Coast, Kulon Progo Regency, Indonesia

The coastal boundary can be optimized for settlement and agriculture site based on a spatial plan for Kulon Progo Regency 2012–2032 within a minimum distance of 100m from the coastline. The location of ring 1 local transmigration settlement on the Bugel Coast is less than 100 m. The increasing trend in coastal erosion caused by climate change is a major contributing factor to the reduction of coastal borders. Thus, rapid assessment of coastal erosion vulnerability is necessary to determine an effective coastal management response. This paper aims to analyze the coastal erosion level using vulnerability assessment, geomorphology of coastal areas, and community resilience impact. The methods used in the mapping of coastal segments are smartline and coastal vulnerability index (CVI). The Smartline method is depicted with a line that runs along the coast with information on geomorphological conditions, whereas the CVI method will give weight to each physical parameter of coastal erosion vulnerability. Results showed that the average area of Bugel Coast decreased by 4,794.94 m2 /year and retreated by 4.36 m/year until the borders become closer to one another, thereby threatening the settlement area. The coastal erosion vulnerability was dominated by a moderate level of 325.14 m (30.48%) to a high level of 322.31 m (30.22%) of the total study areas. This result indicated the huge risk of coastal erosion. Therefore, effective community adaptation and mitigation strategies should be considered to reduce the degradation of coastal border resources and ensure the sustainability of local life, such as the combination of structural and non-structural mitigations that prioritize the sustainability of coastal ecosystems.

Coastal Vulnerability: A Brief Review on Integrated Assessment in Southeast Asia

Coastal zones are an essential part of maintaining sustainability in the world. Coastal regions have gained importance due to various factors, including high ecological production, dense population, industry compatibility, waste disposal, leisure, transportation, and development of military strategies. Coasts are often on the move and must adapt while nature constantly works to maintain balance. Southeast Asia has gained prominence due to its rich ecosystem, high productivity, and densely populated coastal region. In light of this, the coastlines of Southeast Asia are threatened by various factors, including global climate change and human activities. These factors exacerbate the shoreline erosion, frequent catastrophic events, rising sea levels, and saltwater intrusion. Coastal management has become one of the most important challenges of the past decade. The coastal vulnerability index (CVI) was developed to identify and manage vulnerable locations along the coast. Thus, this review attempts to summarize coastal vulnerability in Southeast Asian based on journals and reports. Topics covered include: (1) introduction to coastal vulnerability, (2) methods for determining coastal vulnerability, (3) factors influencing coastal vulnerability (4) associated coastal vulnerability, (5) assessment gaps, and (6) further courses of action. Consequently, assessment of coastal vulnerability will support Southeast Asian coastal communities in guiding mitigation strategies to manage coastal threats in future climate change and urban development.

Coastal Vulnerability Assessment Along The North Java Coastlines-Indonesia

The north coast of Java is an area with very diverse maritime activities. These high activities threaten the ecosystem and environmental sustainability. Several areas already experience environmental degradation and most of the threats come from ocean pollution, coastal erosion, continuous tidal flood (rob), and coastal land subsidence. Furthermore, the coastal degradation is worsened by climate change which may cause the area more vulnerable to disaster. This study aims at evaluating the coastal vulnerability using weighted coastal vulnerability index (CVIw). The method calculates coastal vulnerability by weighting physical coastal parameters using Analytical Hierarchy Process (AHP). CVIw calculation result shows that the vulnerability is dominant at high (39%) and very high (51%) classes. The high vulnerability occurs in Tangerang, Bekasi, Brebes, Demak, Jepara, Pati, and Rembang Regencies. Meanwhile, very high vulnerability takes place in several regencies: Serang, Karawang, Subang, Indramayu, Cirebon, Tegal, Kendal, Semarang, and Gresik. The parameters of relief, coastal features, tidal range and shoreline give contribution more in coastal vulnerability besides lithology, sea level change, and wave height. Identifying vulnerability in these areas might help local governments to prioritize their action plan in coastal disasters mitigation.

Impact of Coastal Disasters on Women in Urban Slums: A New Index

Coastal hazards, particularly cyclones, floods, erosion and storm surges, are emerging as a cause for major concern in the coastal regions of Vijayawada, Andhra Pradesh, India. Serious coastal disaster events have become more common in recent decades, triggering substantial destruction to the low-lying coastal areas and a high death toll. Further, women living in informal and slum housing along the Vijayawada coastline of Andhra Pradesh (CAP), India, suffer from multiple social, cultural and economic inequalities as well. These conditions accelerate and worsen women’s vulnerability among this coastal population. The existing literature demonstrates these communities’ susceptibility to diverse coastal disasters but fails to offer gender-specific vulnerability in urban informal housing in the Vijayawada area. Accordingly, the current study developed a novel gender-specific Women’s Coastal Vulnerability Index (WCVI) to assess the impact of coastal disasters on women and their preparedness in Vijayawada. Field data was collected from over 300 women through surveys (2) and workshops (2) between November 2018 and June 2019, and Arc-GIS tools were used to generate vulnerability maps. Results show that women are more vulnerable than men, with a higher death rate during coastal disaster strikes. The current study also found that gender-specific traditional wear is one of the main factors for this specific vulnerability in this area. Furthermore, the majority of the women tend to be located at home to care for the elders and children, and this is associated with more fatalities during disaster events. Homes, particularly for the urban poor, are typically very small and located in narrow and restricted sites, which are a barrier for women to escape from unsafe residential areas during disasters. Overall, the research reveals that most of the coastal disaster events had a disproportionately negative impact on women. The results from this present study offer valuable information to aid evidence-based policy- and decision-makers to improve existing or generate innovative policies to save women’s lives and improve their livelihood in coastal areas.

Determination of vulnerable zones along Brahmapur coast, Odisha using AHP and GIS with validation against multiple cyclones.

The Brahmapur is the southernmost sub-division of Ganjam district of the Odisha coast frequently prone to cyclones. This coastal stretch is one of the low-lying areas of Odisha with dense population. Recent severe cyclones such as Phailin and Titli crossed the considered coastal stretch in 2013 and 2018 respectively causing severe damages to life and property. Identification of the coastal vulnerability index of such low lying areas is vital to plan effective mitigation measures and better preparedness to hazards. In this view, the Coastal Vulnerability Index (CVI) of the coastal stretch was attempted in the present study using analytical hierarchical process (AHP). The Physical Vulnerability Index (PVI) and Social Vulnerability Index (SVI) were integrated to obtain the Coastal Vulnerability Index. The approach of the study included pair-wise ranking of parameters based on their relevance and importance to the objective of the study. The CVI assessment indicated 22.2% of the coastal stretch with very high risk, 44.5% with high and 24.4% with moderate risk stretches with discontinuous small stretches of 9% with low-risk areas. The outcome of the study was validated with the cyclone crossing tracks of Phailin and Titli which exhibited good correlation with the CVI zones identified from the study. The determined vulnerable zones are useful for mitigation measures and better preparedness during such cyclone hazards in future. Advance techniques of Remote Sensing and Geographic Information System (GIS) integrated spatially with AHP derived data were used in the present study.

Wave modeling with unstructured mesh for hindcast, forecast and wave hazard applications in the Mediterranean Sea

A wave model based on an unstructured grid in the Mediterranean Sea is presented, which provides high-resolution in near-shore regions using the wave model WAVEWATCH III v6.07. The hindcast comprises hourly time series of integrated wave parameters and 2D directional spectra in selected locations, from January 1st 1979 until December 31st 2020, whereas a daily forecast simulation provides predictions for the following 5 days. The hindcast is validated against buoys and several satellite missions. Results show that the model provides a good performance for storm events and mean conditions in the Mediterranean Sea with normalized mean absolute error (NMAE) lower than 15% in 70% of the basin, spatial index of agreement (d1) above 0.6, and the model under/overestimations are below 35% compared with in-situ data. Next, a methodology for coastal risk assessment is developed, leveraging the detailed information provided by the model in shallow waters and relying on a Storm Power Index (SPI), Coastal Vulnerability Index (CVI) and Risk Index (RI). The methodology is applied to the coast of Liguria, Italy, as a region with a high social, economical and touristic value which has experienced catastrophic coastal flooding episodes in recent years. Results of risk assessment were presented for the storm event of October 2018, known to have caused severe damages in the Ligurian coastline. The results provide a SPI of 3 and 5 at the beginning and peak of the storm, respectively, leading to RI of 3–5 depending on the characteristics and socioeconomic importance of the coastal stretches. Therefore, it is concluded that the methodology estimates the risk in an efficient and adequate way for its implementation in an operational risk forecasting system.

Vulnerability of Coastal Communities to Sea Level Rise in Brass Local Government Area, Nigeria

Coastal communities are continuously under threat of survival due to sea level rise, which has increased their vulnerability to inundation resulting to loss of livelihood, property and land area. Hence, this study investigated the vulnerability of the communities in the Brass coast to the impacts of sea level rise. Three communities (Twon-Brass, Okpoama and Diema) located within 0 – 1.2km from the shoreline, and where economic activities are prominent were purposively selected for the study. To assess the level of vulnerability of these communities to sea level rise, the coastal vulnerability index method comprising of six variables (topography, geomorphology, relative sea level rise rate, annual shoreline erosion rate, proximity to coast and population growth rate) were adopted. Landsat imageries at 10years interval for the period 1999 to 2019 were acquired to analyze the Brass shoreline dynamics. The results revealed that for a period of 20 years (1999-2019), the Brass coast has experienced a net land loss of 364.0km2 and a projected land loss of 910km2 by 2050, based on the current scenario. The study further revealed that Twon-Brass and Okpoama communities have high risk of inundation due to sea level rise with a calculated coastal vulnerability index values of 23.1 and 25.3, respectively; while Diema community had moderate risk of being inundated with a coastal vulnerability index value of 21.9. The study recommends the development of an integrated mitigation and adaptation strategy that would increase the resilience of the coastal communities to withstand the threat of sea level rise.

Coastal Vulnerability Assessment: A Case Study of the Nigerian Coastline

Coastal regions are one of the essential spots on the earth as they are hosts to various important ecosystems, natural resources and the increasing population. Based on their proximity to the seas, they are mainly affected by sea-level rise, which is one of the adverse effects of climate change. This has resulted in associated hazards, such as beach erosion, flooding, coastal inundation, habitat destruction, saltwater intrusion into ground water aquifers and ecosystem imbalance. This study quantifies and classifies the vulnerability of the Nigerian coastline to these threats using the analytical hierarchical approach. This involved calculating the coastal vulnerability index (CVI) employing physical and geomorphological variables, and socioeconomic indicators that characterized the coastline vulnerability. The Nigerian coast was divided into seventeen (17) segments based on geomorphic units. The different vulnerability variables were assigned ranks ranging from 1 to 5, with 5 indicating the highest and 1 indicating the lowest vulnerabilities. The geomorphological and physical parameters include coastal slope, bathymetry, geomorphology, wave height, mean tidal range, shoreline change rate and relative sea-level rise, while the socioeconomic parameters include population, cultural heritage, land use/land cover and road network. The calculated CVI values (Saaty method) ranged from 11.25 to 41.66 with a median value of 23.60. Based on Gornitz approach, the calculated measures ranged between 3.51–4.77 and 3.08–5.00 for PVI and SoVI, respectively. However, the aggregated coastal vulnerability index computed using this approach ranged from 3.29 to 4.70. The results obtained from both approaches showed that 59–65% of the entire Nigerian coastline is under moderate to high vulnerability to sea-level rise. Data indicted how the coastal populations are highly vulnerable to both physical–geomorphological and socioeconomic stressors. Coastal vulnerability maps, highlighting the physical–geomorphological and socioeconomic vulnerability status of Nigerian coastline were also generated. The information from this study will assist coastal planners in identifying vulnerable segments in the study area and subsequently aid decisions that would mitigate the predicted impacts in the region.

Assessment of the Coastal Vulnerability Index (CVI) for disaster mitigation strategies in some coastal tourism areas in Gunungkidul, Yogyakarta-Indonesia

South coastal area of Gunungkidul, Yogyakarta-Indonesia has a high tourism development due to the unique physical conditions of coastal typology. However, during the last few years, extreme wave height associated with cyclones damaged many tourist facilities there. Coastal management for ecosystem sustainability requires disaster mitigation, which one considering the aspect of vulnerability. This study aims to assess the level of coastal vulnerability according to coastal typology of Baron-Pok Tunggal section and to determine the coastal management model based on the level of vulnerability. The Coastal Vulnerability Index (CVI) is used in vulnerability assessment. The variable formulation of CVI is divided into hydrodynamic factors (mean significant wave heights, mean tide range, and mean sea level rise) and morphodynamics factors, i.e. geomorphology, coastal slope, and average width of emerged beach. The morphodynamics data were obtained through observation, direct measurements in the field by systematic sampling, extraction from aerial photographs and digital surface model (DSM). The results of modeling and predictions by several agencies are derived to obtain the hydrodynamics data. The result of this study revealed that marine deposition coast typology have a high and moderate vulnerability (twelve and eleven coastal units, respectively). Meanwhile, a low vulnerability can be found in the cliff coast or wave erosion coast typology (24 units). The convex or concave beaches tend to be more vulnerable than beaches with the straight form. The beaches of Buluk, Drini, Kosakora, Sarangan and all beaches from Krakal to Indrayanti have a high vulnerability. Geomorphological variables, significant wave height, and sea level rise have the strongest influence on vulnerability. Coastal management in the marine deposition coast typology can be carried out either in a protective manner or by accommodative approach, such as by observing changes in natural conditions due to sea level rise.