City Resilience towards Coastal Hazards: An Integrated Bottom-Up and Top-Down Assessment

: Community resilience is increasingly required to adapt to the e ﬀ ects of the frequency and severity of the ever-increasing number of coastal hazards. This paper uses the case study of the city of Banda Aceh, Indonesia, which was devastated by the 2004 Indian Ocean Tsunami, with the aim of investigating the city’s level of resilience towards coastal hazards. This paper aims to: (i) assess the preparedness of coastal communities; (ii) evaluate the level of resilience of the city to coastal hazards; and (iii) formulate strategic steps in an e ﬀ ort to mitigate coastal hazards in Banda Aceh. The evaluation was conducted using mixed methods (both quantitative and qualitative) through data triangulation. Data collection involved 311 household surveys, two focus group discussions with 30 participants, and interviews with seven representatives from government and non-government organisations. Regarding the survey, the preparedness level of Banda Aceh’s residents is categorised as “low“. The results of overall city resilience assessments are also classiﬁed as “low”. This ﬁnding indicates that more planned, systematic, and sustainable e ﬀ orts are needed. Hence, this study also recommends strategies to enhance resilience in dealing with coastal hazards.


Introduction
Over the coming decades, demographic trends are likely to confirm that more and innumerable people are living in areas that are vulnerable to disaster risk. Currently, a significant proportion of the world's population is living in coastal regions. Regrettably, coastal areas are highly susceptible to the impacts of global climate change and the intensity of coastal hazards, such as erosion, storm surges, flooding, and tsunamis [1][2][3][4][5].

Figure 1.
Map of Banda Aceh with area of Tsunami damages (geographic coordinate system is UTM) [33].
Banda Aceh is one of the coastal cities in Aceh Province, Indonesia, with a moderate demographic size. At the end of 2018, Banda Aceh had a population of 265,111, with a density of 4321 people/ km 2 . The highest population is in Kuta Alam Subdistrict, which is 52,645 people, whereas the highest population density is in Baiturrahman Subdistrict, with 8250 people/ km 2 . Compared to the population in 2017, amounting to 259,913 people, the growth rate of the residents of Banda Aceh is 2%. This percentage is higher than the average population growth rate in Aceh Province in 2018 at 1.77% [38,39].

Methodology
To address the research objectives, this study was conducted in three stages, namely: i) evaluation of coastal community preparedness, ii) assessment of the level of the city's resilience to coastal hazards, and iii) formulation of recommendations and strategic actions to enhance the city's resilience toward coastal hazards.
The city's resilience study was carried out using a quantitative and qualitative (mixed-method) approach through the triangulation of data/source. The data triangulation technique involves comparing and checking the degree of trust in the information obtained over different times (months) and using different tools. The expected result of the comparison is in the form of similarities or reasons for differences [40]. Data collection was carried out through several measures, including household survey, focus group discussion (FGD), and interviews. The flowchart methodology of this study is shown in Figure 2.

Methodology
To address the research objectives, this study was conducted in three stages, namely: (i) evaluation of coastal community preparedness, (ii) assessment of the level of the city's resilience to coastal hazards, and (iii) formulation of recommendations and strategic actions to enhance the city's resilience toward coastal hazards.
The city's resilience study was carried out using a quantitative and qualitative (mixed-method) approach through the triangulation of data/source. The data triangulation technique involves comparing and checking the degree of trust in the information obtained over different times (months) and using different tools. The expected result of the comparison is in the form of similarities or reasons for differences [40]. Data collection was carried out through several measures, including household survey, focus group discussion (FGD), and interviews. The flowchart methodology of this study is shown in Figure 2. Oktari et al. (2020) had previously developed the instrument that is used to study city resilience [41]. This instrument consists of five resilience parameters (4 variables, 16 indicators each), including (i) institutional/governance, (ii) social and economic, (iii) coastal resource management, (iv) land use management and infrastructure, and (v) adaptation and mitigation strategies.
Rating indicators were scored into: (i) 0 (no information); (ii) 1 (no known plans/strategy/process); (iii) 2 (there is a plan/strategy/process in existence but it has a known weakness); (iv) 3 (there is a plan/strategy/process in place and it is effective) and (v) 4 (there is a plan/strategy/process in place and it is sustained). Oktari et al. (2020) had previously developed the instrument that is used to study city resilience [41]. This instrument consists of five resilience parameters (4 variables, 16 indicators each), including i) institutional/ governance, ii) social and economic, iii) coastal resource management, iv) land use management and infrastructure, and v) adaptation and mitigation strategies.
Rating indicators were scored into: i) 0 (no information); ii) 1 (no known plans/ strategy/ process); iii) 2 (there is a plan/ strategy/ process in existence but it has a known weakness); iv) 3 (there is a plan/ strategy/ process in place and it is effective) and v) 4 (there is a plan/ strategy/ process in place and it is sustained).
Analysis of the calculation of the score of each parameter was performed using the Formula (1): Parameter Score Sum of all indicator scores Number of indicators The resilience score was calculated using the Equation (2): Resilience Score Sum of all parameter scores Number of parameters The resilience scores ranged between 0 and 4, and were divided into three categories: i) Low (<3) resilience; ii) Medium (3-4) resilience; and iii) High (>4) resilience.
Some of the details that are needed to complete the city's resilience assessment were obtained from the results of the community preparedness survey. The parameters used to assess the preparedness of coastal communities were adopted from a framework developed by LIPI-UNESCO [42]. The latter has developed appropriate indicators and key questions to determine community preparedness in facing the impacts of rising sea levels due to climate change and other coastal hazards. Data collection techniques were carried out using questionnaires and interviews.
In this study, the respondents were individuals who represent households. Data were collected in four (4) sub-districts in Banda Aceh, namely Syiah Kuala, Kuta Raja, Kuta Alam, and Meuraxa. A total of 311 respondents were selected with a purposive random sampling technique, whereby the chosen respondents were located in coastal areas.
The results of the questionnaire were analysed using an index to measure the level of community preparedness in dealing with coastal hazards. The questions in this parameter are assumed to have the same value, that is, if the correct answer is worth "1" and the answer is wrong or answer "don't know" is worth "0". The index value calculation uses the following Formula (3): Total Riil Parameter Score Analysis of the calculation of the score of each parameter was performed using the Formula (1): The resilience score was calculated using the Equation (2): Resilience Score = Sum of all parameter scores Number of parameters (2) The resilience scores ranged between 0 and 4, and were divided into three categories: (i) Low (<3) resilience; (ii) Medium (3-4) resilience; and (iii) High (>4) resilience.
Some of the details that are needed to complete the city's resilience assessment were obtained from the results of the community preparedness survey. The parameters used to assess the preparedness of coastal communities were adopted from a framework developed by LIPI-UNESCO [42]. The latter has developed appropriate indicators and key questions to determine community preparedness in facing the impacts of rising sea levels due to climate change and other coastal hazards. Data collection techniques were carried out using questionnaires and interviews.
In this study, the respondents were individuals who represent households. Data were collected in four (4) sub-districts in Banda Aceh, namely Syiah Kuala, Kuta Raja, Kuta Alam, and Meuraxa. A total of 311 respondents were selected with a purposive random sampling technique, whereby the chosen respondents were located in coastal areas.
The results of the questionnaire were analysed using an index to measure the level of community preparedness in dealing with coastal hazards. The questions in this parameter are assumed to have the same value, that is, if the correct answer is worth "1" and the answer is wrong or answer "don't know" is worth "0". The index value calculation uses the following Formula (3): The index value is in the range of 0-100. The higher the index value, the greater the level of preparedness. Index values are divided into the following categories: (i) Very high (80.00-100); (ii) High (60.00-79.99); (iii) Moderate (40.00-59.99); (iv) Low (39.99-20); and (v) Very low (0-19.99).
Water 2020, 12, 2823 6 of 22 The first FGD was held on 14 September 2018. The FGD aimed to conduct an initial assessment of the city resilience of Banda Aceh towards coastal hazards. The FGD participants consisted of 30 people who were experts and practitioners in the field of climate change and disasters, both from the local and national levels, which included elements of government, non-government, and academics. The second FGD was carried out on October 9, 2019 and was intended to further investigate the city resilience of Banda Aceh towards coastal hazards. This FGD also facilitated the Strengths Weakness Opportunities Threats (SWOT) analysis to identify recommendations and strategic measures with which to advance the city's resilience toward coastal hazards.
Interviews were conducted with seven people who represented government agencies and Non-Governmental Organisations (NGOs) to compare or check the results of the FGDs that had been undertaken and to obtain more in-depth information. Interviews were conducted from December 2018 to March 2019.

Coastal Community Preparedness in Banda Aceh
A total of 311 respondents representing households in the four sub-districts in Banda Aceh were approached and interviewed. The demographic characteristics of the respondents are presented in Table 1. Most of the respondents were 30-39 years old (35.37%), and the majority (67.52%) were women. Around 42.44% of the respondents had graduated from high school, and almost half (45.98%) of the respondents were employees. As many as 46.30% of the respondents' houses were less than 500 m from the shoreline. The majority of respondents were direct cash transfer recipients (82.96%) and owned welfare cards for low-income families (91.00%), while the percentage of respondents who received the rice-for-poor scheme was 36.66%.
The results of the coastal community preparedness study are reported based on four (4) parameters, namely: (1) knowledge of coastal hazards, (2) emergency response plans, (3) early warning, and (4) resource mobilisation.

Knowledge of Coastal Hazards
Knowledge of coastal hazards was measured by several indicators, namely, the impact of sea-level rise, tidal flood characteristics, and signs of a tsunami. Some tsunami signs include an earthquake that makes it difficult to stand, seawater receded suddenly, powerful and unusual noises from the sea (like explosions), and giant waves on the horizon. Individuals or households who have a good level of knowledge are assumed to be better prepared to take anticipatory efforts to deal with coastal hazards that might occur, because knowledge is the foundation of awareness to perform emergency response plans, early warning, and the mobilising of resources.
From the analysis of the questionnaire, the respondents' knowledge of coastal hazards is still lacking. Some respondents (40-50%) were aware that rising sea levels have an impact on the occurrence of floods and submerged coastal areas. Further, a few (<50%) respondents thought that rising sea levels also generated a clean (potable) water crisis, infrastructure damaged, decreased fishery production, and lost tourism attractiveness.
The results of the study also showed that there was still a misconception of knowledge about tsunami signs. The majority of respondents thought that the signs of a tsunami, including that triggered by a powerful earthquake, mean that people could not stand up on their feet, and that they would be followed (entrapped) by the receding seawater. Every tsunami event is not necessarily preceded by strong earthquakes and receding seawater, and examples of this are: Pangandaran Tsunami on 17 July 2006, Mentawai on 26 October 2010, and the Palu-Donggala 2018. Further, unlike most of the tsunamis that have occurred in Indonesia, the 2018 Sunda Strait Tsunami was not generated by an earthquake [43][44][45][46].
Knowledge dissemination is inseparable from the role of media that would broadcast information to the public. Based on the results of the present study, the common sources of the respondents' knowledge were from relatives, friends, and neighbours (82, 90%), and TV (79, 03%).
Despite the fact that the coastal area of Banda Aceh was the most severely affected in the 2004 tsunami, it turns out there are still some people who claim to have received little information about the tsunami. As for the rising sea levels, the majority of respondents claimed not to have been exposed to adequate information about this hazard. This situation occurs because the community has not felt the impact directly, given the rising sea levels, causing a negative impact at a slow pace and over a long period of time, but with a high degree of certainty.

Emergency Response Plan
Emergency response plans are an important component that need to be equipped in the context of community preparedness towards coastal hazards, especially tsunamis. In this study, the emergency response plan was measured by asking about anticipatory steps that are taken by the respondents if a coastal hazard occurs, as well as about access to basic services (water, electricity, sanitation, etc.).
The majority of respondents have recognised the hazards in their environment (65.16%) and they consequently prepare clothes, cash, and family emergency needs (75.81%). Few respondents had developed evacuation plans, identified safe points, and practiced evacuation plans with families (around 20-30%). This condition is miserable, considering that the coastal area received more attention Most of the people of Banda Aceh have access to electricity services (97.42%), clean (potable) water (82.58%), and information/communication (65.48%). However, for sanitation services and public transportation, the percentage is still low at 54.52% and 31.61%, respectively.

Early Warning System
An adequate early warning would be very beneficial for the community, in order to avoid the risks that may occur. Early warning consists of a combination of both the technological capability and the human ability to follow up on the results of the early warning. Early warning, as part of disaster risk reduction, is not only about technically accurate warnings, because it must also build a solid understanding of the risk of a warning, establish relationships between providers and warning users, and also increase the ability of authorities and communities to react appropriately to early warnings. If one of these components has not been accorded, then the early warning system will not succeed as a whole [47].
The results of our data analysis show that almost all respondents were exposed to the tsunami early warning system (93.87%). This state could be achieved due to the routine activation of tsunami sirens by the government on the 26th of every month. The primary purpose of establishing a tsunami early warning system is to save lives and reduce the loss of life and damage. If a series of procedures is accurately carried out, suffering from the tsunami disaster can be minimised.
Most of the respondents (71.29%) stated that the government is a source of early warning information. For the dissemination of early warning information to be effective, it requires the involvement of various parties in various sectors at all levels, including government, communities at risk, community organisations, Non-Governmental Organisations (NGOs), the media, and the private sector. Without the involvement of various stakeholders, the early warning system will not be adequate [47]. Whether or not warnings are remitted to communities in disaster-risk areas depends on their awareness and the ability of those communities to carry out the roles and responsibilities of all actors in the communication chain.
Some respondents (61%) perceived the siren noises to be an automatic response to disaster, where, in fact, the siren should be activated manually, by a particular person at a particular location. Some respondents (75.16%) also conceived that if a siren noise is given, it indicates that a tsunami will occur. Significantly, the siren is activated as an evacuation order to find, move to, and reach a safer place when a potential tsunami occurs.

Resource Mobilisation
The parameters of resource mobilisation were valued based on community actions, training programmes (resources), and access. The study also revealed that there were several actions taken by some respondents to anticipate coastal hazards, such as having savings, insurance, land/house in a potentially less harmful position, other livelihoods and relatives/friends for protection. Except for having relatives/friends, the overall alternative preparation was only claimed by less than 20% of respondents.
Only 35% of respondents have participated in training/workshop programmes on coastal hazard mitigation, first aid training, victim search and rescue, and clean (potable) water treatment. Access to preparedness information, emergency communication tools, transportation for evacuation, and health facilities was owned by more than 46% of respondents.

Community Preparedness Index
The Community Preparedness Index calculation for each parameter showed that the majority of Banda Aceh residents are still not prepared to withstand coastal hazards. This interpretation can Water 2020, 12, 2823 9 of 22 be justified from the distribution of respondents' in the category of "moderate" and "low" levels of preparedness for each parameter, and as a whole (see Figure 3).
Water 2020, 12, x FOR PEER REVIEW 9 of 24 justified from the distribution of respondents' in the category of "moderate" and "low" levels of preparedness for each parameter, and as a whole (see Figure 3). For the parameter of knowledge of coastal hazards and emergency response plans, most of the respondents are in the category of "moderate", with percentages of 45.02% and 35.37%, respectively. Furthermore, the majority of inhabitants are in the "low" category for early warning (55.31%) and resource mobilisation (46.30%).
The level of community preparedness is defined as the cumulative index value of each parameter (knowledge of coastal hazards, emergency response plans, early warning, and resource mobilisation). The majority of respondents (54.02%) had a low level of preparedness. While the respondents in the high and moderate categories were 10.29% and 27.65%, respectively. The remaining 8% of respondents fell into the "very low" category.
The spatial analysis of the respondent's level of preparedness toward coastal hazards is visualized in Figure 4. For the parameter of knowledge of coastal hazards and emergency response plans, most of the respondents are in the category of "moderate", with percentages of 45.02% and 35.37%, respectively. Furthermore, the majority of inhabitants are in the "low" category for early warning (55.31%) and resource mobilisation (46.30%).
The level of community preparedness is defined as the cumulative index value of each parameter (knowledge of coastal hazards, emergency response plans, early warning, and resource mobilisation). The majority of respondents (54.02%) had a low level of preparedness. While the respondents in the high and moderate categories were 10.29% and 27.65%, respectively. The remaining 8% of respondents fell into the "very low" category.
The spatial analysis of the respondent's level of preparedness toward coastal hazards is visualized in Figure 4.
Overall, the calculation of the Banda Aceh people's Preparedness Index value is provided in Table 2. All parameters indicate the index value in the "moderate" and "low" categories. The lowest index score is for the warning system parameter. The total index of community preparedness towards coastal hazards falls in the "low" category, with an index value of 36.97. Overall, the calculation of the Banda Aceh people's Preparedness Index value is provided in Table 2. All parameters indicate the index value in the "moderate" and "low" categories. The lowest index score is for the warning system parameter. The total index of community preparedness towards coastal hazards falls in the "low" category, with an index value of 36.97.

Banda Aceh City's Resilience towards Coastal Hazards
The city resilience study on the impact of coastal hazards used five resilience parameters, namely: (1) institutional/governance, (2) social economy, (3) management of coastal resources, (4) management and infrastructure of land use, and (5) risk reduction strategies.

Institutional/Governance
The institutional and governance parameters, in general, report a range of scores between 1 and 3, as shown in Figure 5. Only indicators in basic service variables have a score of 3 (Id121, Id122, Id123, and Id124). The household surveys also strengthened this result, where access to the coastal community of Banda Aceh for electricity and clean (potable) water services had been obtained by 92.42% and 82.58% of respondents, respectively. At this time, people get access to electricity from the National Electricity Company (Perusahaan Listrik Negara/PLN). By 2018, 99.52% of households in the Banda Aceh had electricity accessed from PLN, and the rest from privately generated electricity services (0.48%) [33,34].
Banda Aceh does not have a policy or planning document that is specifically aimed at protecting coastal areas. However, at the provincial level, Aceh already has a Zoning Plan for Coastal Areas and Small Islands (Rencana Zonasi Wilayah Pesisir dan Pulau-Pulau Kecil/RZWP3K) 2020-2040. This document aims to regulate all activities that use coastal space within Aceh's jurisdiction that can be well integrated and able to provide more optimal results, which contain specific measures that are related to the use of coastal areas.
Id123, and Id124). The household surveys also strengthened this result, where access to the coastal community of Banda Aceh for electricity and clean (potable) water services had been obtained by 92.42% and 82.58% of respondents, respectively. At this time, people get access to electricity from the National Electricity Company (Perusahaan Listrik Negara/ PLN). By 2018, 99.52% of households in the Banda Aceh had electricity accessed from PLN, and the rest from privately generated electricity services (0.48%) [33,34]. Banda Aceh does not have a policy or planning document that is specifically aimed at protecting coastal areas. However, at the provincial level, Aceh already has a Zoning Plan for Coastal Areas and Small Islands (Rencana Zonasi Wilayah Pesisir dan Pulau-Pulau Kecil/ RZWP3K) 2020-2040. This document aims to regulate all activities that use coastal space within Aceh's jurisdiction that can be well integrated and able to provide more optimal results, which contain specific measures that are related to the use of coastal areas.

Social Economy
The results of the FGD acknowledges that the majority of indicators in the parameter of social and economic (Figure 6) are at a value of 2, meaning that a plan/strategy does exist, but it is not yet effective. Most indicators on the variable livelihood reach a value of 3 (Id221, Id222, Id223).
This condition implies that the people of Banda Aceh have alternative livelihoods, aside from being a fisherman, for example. The number of fishermen in Banda Aceh in 2018 was 1300, while fishery farmers were 401. There were 44 fishpond farmer groups and 61 fishermen groups in Banda Aceh. The number of small and medium-sized businesses in Banda Aceh in the field of trade was 6507, of agriculture 10, and of fisheries 20 [38]. and economic (Figure 6) are at a value of 2, meaning that a plan/strategy does exist, but it is not yet effective. Most indicators on the variable livelihood reach a value of 3 (Id221, Id222, Id223).
This condition implies that the people of Banda Aceh have alternative livelihoods, aside from being a fisherman, for example. The number of fishermen in Banda Aceh in 2018 was 1300, while fishery farmers were 401. There were 44 fishpond farmer groups and 61 fishermen groups in Banda Aceh. The number of small and medium-sized businesses in Banda Aceh in the field of trade was 6507, of agriculture 10, and of fisheries 20 [38].

Coastal resource management
Based on the results of the study, the implementation and monitoring of coastal resources, habitat protection, community involvement in planning, implementation, and monitoring and investment in conservation management have not been effective. The consensus agreed to rate a score of two for all indicators (see Figure 7), except for Id313 (score 1) and Id321 (score 3).

Coastal Resource Management
Based on the results of the study, the implementation and monitoring of coastal resources, habitat protection, community involvement in planning, implementation, and monitoring and investment in conservation management have not been effective. The consensus agreed to rate a score of two for all indicators (see Figure 7), except for Id313 (score 1) and Id321 (score 3).
The The involvement of the community in planning, implementation, and monitoring of coastal protection programmes was also strengthened by the results of the household survey. The respondents stated that only a few members of the community were directly involved in programme planning (26.45), programme implementation (24.52), problem-solving (23.23%), and programme monitoring (22.58%).

Management and infrastructure of land use
Overall, the assessment of indicators on the management and infrastructure of land-use parameters ( Figure 8) attained a score of two, except for Id411 and Id413 (score 3) and Id442 and Id443 (score 1).
The results of the study indicated that education, research, and training related to land use management and infrastructure have not been conducted. Land-use policies and building standards have been partially effective. According to BPS data (2019), all urban and rural roads in Banda Aceh are asphalt covered with a length reaching 707,343 m. Around 80.55% are in good condition, but the rest are in a state of moderate to severe damage.

Management and Infrastructure of Land Use
Overall, the assessment of indicators on the management and infrastructure of land-use parameters ( Figure 8) attained a score of two, except for Id411 and Id413 (score 3) and Id442 and Id443 (score 1).  The results of the study indicated that education, research, and training related to land use management and infrastructure have not been conducted. Land-use policies and building standards have been partially effective. According to BPS data (2019), all urban and rural roads in Banda Aceh are asphalt covered with a length reaching 707,343 m. Around 80.55% are in good condition, but the rest are in a state of moderate to severe damage.
The ratio of the number of buildings that obtained a building permit in the coastal area also shows that there are still many illegal buildings. In the Kuta Raja sub-district, 68.32% (

Risk Reduction Strategy
Regarding the assessment of the indicators on the parameters of risk reduction strategy, the majority were in rating 2-only Id531 and Id541, respectively, were in ratings 3 and 1 (see Figure 9). This result was also strengthened by the household survey, thus explaining why aspects of knowledge about risk, emergency response plans, early warning, and mobilisation of community resources were in the category of unprepared (low level), as described in the results of the previous coastal community preparedness study (see Section 4.1). The overall assessment results of the resilience parameters shown in Figure 10 were low resilience, and the values were in the range of 2 (Parameters 1, 3, 4, and 5) to 2.12 (Parameter 2). The overall assessment results of the resilience parameters shown in Figure 10 were low resilience, and the values were in the range of 2 (Parameters 1, 3, 4, and 5) to 2.12 (Parameter 2).

Strategies and Recommendations to Enhance City Resilience
The SWOT analysis in this study was used throughout interviews and FGDs in order to recognise strengths, weaknesses, opportunities, and threats that encompass the city's resilience to coastal hazards. It is required in order to give an appraisal through internal and external factors as an essential frame of the SWOT analysis. The internal factors influence the configuration of the strengths and weaknesses (S and W, respectively). The external factors influence the creation of opportunities and threats (O and T, respectively).
The SWOT analysis was performed by comparing internal factors with external factors. The internal factors are listed in a matrix called the Internal Strategic Factor Analysis Summary (IFAS). External factors are recorded into an External Strategic Factor Analysis Summary (EFAS) matrix. Both IFAS and EFAS matrices are presented in Table 2 and Table 3, respectively.

Strategies and Recommendations to Enhance City Resilience
The SWOT analysis in this study was used throughout interviews and FGDs in order to recognise strengths, weaknesses, opportunities, and threats that encompass the city's resilience to coastal hazards. It is required in order to give an appraisal through internal and external factors as an essential frame of the SWOT analysis. The internal factors influence the configuration of the strengths and weaknesses (S and W, respectively). The external factors influence the creation of opportunities and threats (O and T, respectively).
The SWOT analysis was performed by comparing internal factors with external factors. The internal factors are listed in a matrix called the Internal Strategic Factor Analysis Summary (IFAS). External factors are recorded into an External Strategic Factor Analysis Summary (EFAS) matrix. Both IFAS and EFAS matrices are presented in Tables 3 and 4, respectively.

W15:
The relative sloping topography causes the more widespread impact of the tsunami and tidal flood W16: Most of the area is located on the coast, which is vulnerable to tsunami threat and tidal flood Demographic Condition S17: Population density on the coast is relatively low, therefore, it is easier to arrange the area S18: There are local wisdom values that contain DRR S19: Interaction and attitudes of togetherness among society W17: No detailed data on vulnerable groups such as the elderly, children, and people with disabilities The mechanism used to classify strategic factors in increasing resilience to coastal hazards is the SWOT matrix. This matrix clearly illustrates how external opportunities and threats encountered by the community can be adjusted by their strengths and weaknesses. This matrix offers four sets of possible strategic alternatives.
Firstly, the SO (Strength-Opportunities) Strategy-build upon the mindset of utilising all the power to seize and take advantage of the maximum opportunities. Secondly, the ST (Strengths-Threats) Strategy-using the strengths that are possessed to overcome threats. Thirdly, the WO (Weaknesses-Opportunities) Strategy-based on the utilisation of existing opportunities by minimising existing weaknesses. Fourthly, WT (Weaknesses-Threats) Strategy, in accordance with activities that are defensive and attempt to minimise current weaknesses and to avoid threats.
Based on the results of the study, strategy recommendations are formulated, as presented in Table 5. In general, there are two types of strategies that need to be counted-first, mitigation efforts, both structural (SO1, SO2, WO1, WO2, and WO3) and non-structural (ST1, ST2, and ST3) to reduce risk and adapt to coastal hazards. Second, integrating policies, data, resources, and programs related to coastal hazards to improve the resilience of cities (WT1, WT2, and WT3).

Discussion
Over the last few decades, coastal areas have been increasingly affected by natural hazards, resulting in increased economic losses and deaths [6,7]. Typically, in coastal areas, the impact of a disaster depends on several factors, including the intensity and frequency of natural hazards, climate change, and coastal stress. However, it is widely assumed that resilient coasts can effectively cope with stresses and impacts of coastal hazards. To build a resilient coast, it is important to assess the level of both community preparedness and coastal resilience [8].
In this context, the overall coastal community preparedness index of Banda Aceh is in the "low" category, with index score 36.97 out of 100. For the parameters of knowledge of coastal hazards and emergency response plans, the analysis results show a "moderate" level of preparedness with index values of 41.52 and 42.39, respectively. Meanwhile, the early warning system and resource mobilisation parameters are at the "low" level with index values of 28.70 and 35.26, respectively. This condition is quite alarming, considering that Banda Aceh is highly vulnerable to coastal hazards. The level of preparedness of a community is dynamic, implying that it can increase or decrease over time. Changes that occur in society, including social, economic, cultural, and political differences, also influence the preparedness condition. For this reason, efforts need to be made to regularly maintain and improve the level of preparedness of the community.
The method of assessing community preparedness in facing coastal hazards that have been used in this study provides necessary information about what is occurring in the field. This information is crucial as a process of thoughtfulness regarding administering an assessment of a city's resilience, especially with respect to the social-economic parameters. Previous studies have shown that the social economy is one of the parameters or aspects used in assessing resilience [48][49][50][51].
In this study, the results of the community preparedness survey in facing coastal hazards were used to assess several indicators in the study parameters of the coastal city's resilience, namely, institutional/governance (Parameter 1), social and economic (Parameter 2), management of coastal resources (Parameter 3), and risk reduction strategies (Parameter 5). In these parameters, several indicators are assessed, based on secondary data (government reports), and validated using primary data that were obtained through community preparedness surveys. Indicators in Parameter 1 that required input from the community survey are the percentage of households that have access to electricity, clean (potable) water, sanitation, and solid waste facilities. In Parameter 2, the percentage of people who work in the agriculture, fishery, and trade sectors also confirmed the survey results. The indicator of community involvement in planning, implementing, and monitoring coastal protection programmes also indicated by way of the survey some support for Parameter 3. The community preparedness survey also provides detailed information on the community's risk knowledge, community access to early warning information and evacuation strategies, emergency response plans, and community mobilisation capacity needed in Parameter 5 of the coastal resilience assessment.
The overall assessment results of the city's resilience in Banda Aceh are low. This result indicates that efforts made to deal with coastal hazards have not been effective. For this coastal hazard assessment/judgment, a more planned, systematic, and sustainable effort is necessary so that the consequences of coastal hazards can be reduced. Accordingly, the study of coastal resilience in this study is also complemented by a SWOT analysis in order to develop strategies and recommendations that would enhance city resilience.
This study confirms the benefits of using quantitative and qualitative approaches (mixed methods) to collect data in order to assess urban resilience through data/source triangulation, whereby the data collection would involve several activities, including household surveys, Focus Group Discussions (FGD), and interviews. The data triangulation technique involves comparing and re-checking the level of confidence in information obtained through different means and at different times. The expected results of the comparisons are similarities or reasons for differences [40].
The results of this study also augment the idea that low-lying or coastal areas have a higher risk of coastal hazards [48]. Rapid population growth, accompanied by a lack of public understanding of disaster risks, has led to the utilisation of buffer zone areas as residential areas. This condition has caused damage to the coastal ecosystems and worsens Banda Aceh's vulnerability to the tsunami and other coastal hazards [33].

Conclusions
This study has expanded an integrative assessment method for evaluating the level of the city's resilience toward coastal hazards. This method is employed by first assessing the level of community preparedness (at the household level) in dealing with coastal hazards, where the results will be adopted when conducting a more comprehensive evaluation of the city's resilience. This bottom-up procedure is essential to ensure that information from the grass-roots level is considered. Whereas the top-down approach is carried out to ensure that the correct conceptual information is still applied. Top-down evaluation of the city's resilience level is performed through interviews and focus group discussions with policymakers, practitioners, and academics.
The application of this method is applied to assess the level of resilience of Banda Aceh, which is a tsunami-prone area, in dealing with coastal hazards. The analysis revealed that the level of preparedness of the people of Banda Aceh was in the "low" category. The city's overall resilience assessment result is also categorised as "low", indicating that more planned, systematic and sustainable effort is required, and therefore, this study also recommends the outlined strategies.
Further research is needed to explore the replication of this method in other coastal hazard-prone regions. It would enable some understanding of how the resilience level towards coastal hazards, as measured by this integrative approach, will adjust due to the social, economic, political, and environmental circumstances.