1.1. A Framework for Supporting Science and Technology to Address Social Challenges in Disaster-Affected Areas amid Increasing Disaster Frequency

In recent years, large-scale natural disasters have been occurring with increasing frequency in Japan and abroad, largely owing to the effects of climate change. In Japan, the shortage of personnel responsible for disaster response has become a critical issue, exacerbated by the declining birthrate, aging population, and shrinking working-age demographics. Under these circumstances, science and technology play a vital role in disaster management.

The Science Council of Japan, which serves as the representative organization of scientists in the country and provides policy recommendations to the government, emphasizes the importance of utilizing science and technology in disaster risk reduction. This proposal stresses the importance of facilitating the effective use of science and technology ¹. To address social issues in disaster-affected areas, particularly in anticipation of large-scale disasters such as the Nankai Trough earthquake, facilitation that bridges the disaster field and advancement of science and technology is essential. Accurately assessing the conditions in disaster-affected areas, and applying science and technology based on such assessments are crucial.

Various initiatives have been undertaken to address social issues in disaster-affected areas by applying science and technology. The Research Institute of Science and Technology for Society of the Japan Science and Technology Agency (JST-RISTEX) ² has played a leading role in advancing research and development programs that focus on solving social challenges and promoting social implementation of science and technology. Moreover, JST-RISTEX has proactively supported disaster risk reduction. “Social implementation” is a term that originated from JST’s concept of “social technology,” which refers to science and technology for the benefit of people and society. It is defined as “applying and deploying research outcomes to solve social issues” ².

1.2. Research and Implementation Efforts by JST-RISTEX in Disaster Risk Reduction

JST-RISTEX has implemented several projects to solve social issues in disaster risk reduction ². For example, one notable initiative is the “Disaster Victim Livelihood Recovery Support System,” which has accumulated a substantial track record in supporting the individual recovery of disaster-affected residents ³. A key feature of these projects is their field-oriented approach: they identify and analyze issues through on-site fieldwork in both disaster-affected and disaster-prone areas, and promote implementing problem-solving strategies by applying science and technology. Furthermore, the results are not limited to individual regions, but are actively being deployed horizontally to other regions by generalizing them.

Among the various programs initiated under this framework is the Evacuation Topography Time Map (commonly referred to as the “NIGECHIZU”) ^4,5,6,7, a tool developed by the volunteer division of Nikken Sekkei in the aftermath of the 2011 Great East Japan Earthquake. This tool visualizes the estimated time required to reach evacuation destinations during a disaster by considering the geographical features, road conditions, and other local factors. Workshop participants use colored pencils and leather cords to demarcate evacuation time zones on a map, which helps them share risk perceptions and encourages dialogue among residents. This method is gradually being adopted across Japan to promote proactive evacuation behaviors.

Although various case studies of its application across different hazards and stakeholder groups have been reported ^8,9, and general overviews have been provided ¹⁰, there remains a lack of academic studies that critically examine the practical realities and challenges of the Evacuation Topography Time Map using rigorous research methodologies. To promote further application of science and technology, examining the actual conditions and challenges of the Evacuation Topography Time Map as a form of social technology is essential. This examination will accelerate the deployment of other scientific and technological solutions to address social issues in disaster-affected areas. Moreover, strengthening the examination from the perspective of promoting further application of “science and technology” in the “field,” with “facilitation” serving as the central conceptual framework is necessary.

1.3. Objectives of the Study

This study aims to clarify the current state and challenges of the Evacuation Topography Time Map by applying academic methodologies to ensure objectivity and reliability in its analysis.

Section 2 provides an overview of the concept and development of the Evacuation Topography Time Map. Section 3 outlines the study design and presents the proposed analytical method. Sections 4 and 5 present the analysis results and discussion, respectively. Section 6 discusses the evaluation of the proposed analytical approach by the study participants.

Using this multistage analysis, this study aims to generate foundational insights that support implementing science and technology to address social issues in disaster-affected areas.

2.1. Risk Communication Using Maps

In Japan, hazard maps are increasingly acknowledged by the public as instruments for risk communication. Several cases have been reported in which their use has promoted timely evacuation and enhanced local risk awareness. However, studies have also indicated that for many citizens, hazard maps can be difficult to understand and use effectively ¹¹.

In response to these limitations, various map-based approaches to risk communication have been developed, including disaster imagination games ¹², problem-identification-based community disaster prevention workshops ¹³, and the Evacuation Topography Time Map ⁴. In recent years, the use of digital technologies and simulation tools has been reported to advance risk communication practices ^14,15,16.

2.2. The Evacuation Topography Time Map

The Evacuation Topography Time Map is a risk communication tool designed to promote a personalized understanding of evacuation during various types of disasters. As of August 2024, it has been implemented in 64 municipalities across 26 prefectures in Japan, reflecting nationwide adoption ⁸. This tool visually represents the distance, estimated evacuation time, and direction of evacuation destinations using color coding along roads on a map, enabling users to grasp critical evacuation information intuitively.

The reported case studies include an initiative in Kamakura City, Kanagawa Prefecture, where local residents were instrumental and subsequently contributed to the improvement of evacuation routes ¹⁷, as well as ongoing annual implementation as part of integrated learning programs in Shimoda City, Shizuoka Prefecture ¹⁸. The Evacuation Topography Time Map has been applied across Japan in diverse contexts, involving various hazards and stakeholder groups.

Currently, the “NIGECHIZU Study Group” ¹⁹, organized under the certified NPO corporation Japan Society of Urban and Regional Planners, is advancing this tool through collaborative efforts across industry, government, and academia. Their initiatives include developing of a qualification system for disaster preparedness facilitators, known as “Disaster NIGECHIZU Practitioners” ²⁰, among other activities (Fig. 1).

2.3. Workshop

The detailed procedure for creating the Evacuation Topography Time Map is illustrated in Fig. 2. The process comprises the following seven steps: (1) identify the type of hazard to be addressed; (2) review hazard maps and confirm expected inundation areas or other risk zones; (3) designate evacuation destinations; (4) identify obstacles to evacuation; (5) visualize evacuation time by coloring routes to evacuation points and recording observations on sticky notes; (6) conduct a reflective discussion; and (7) present the results.

The Evacuation Topography Time Map is easy to create, even for elementary school students, using simple tools such as a blank map, colored pencils, and leather cords.

3.1. Interview Survey Informed by the Principles of Disaster Ethnography

Disaster ethnography is a methodological approach used to extract tacit knowledge related to disaster response from affected individuals and translate it into explicit, shareable knowledge ^22,23. Rooted in the traditions of cultural anthropology, this method seeks to visualize the lived realities of disaster response as narrated by those directly involved. Although traditional ethnography primarily aims to understand other cultures, often within the context of colonialism or subcultural studies, its application in the disaster risk reduction field has been increasingly standardized to allow for internal understanding and systematic sharing of on-the-ground knowledge ²⁴.

The disaster ethnographic approach typically includes: (1) the use of non-structured interviews, (2) the chronological unfolding of topics, and (3) a perspective that facilitates extracting the lessons learned. In this study, these principles were adapted to explore the implicit knowledge surrounding the Evacuation Topography Time Map and strengthen our understanding of its development from inception to the present. Accordingly, semi-structured interviews were conducted to enable participants to express themselves freely within their own contextual experiences.

The interviews focused on three primary themes: (1) current involvement, how the participant has been engaged with the Evacuation Topography Time Map; (2) ideal vision, what the participant considers an ideal state for advancing the initiative; and (3) challenges, what obstacles exist in achieving that ideal. Interviewees were encouraged to chronologically recount their experiences, including their initial involvement, the evolution of their efforts, and the insights they obtained throughout the process.

3.2. Comparative Analysis

3.2.1. Quantitative Text Analysis

In this study, a quantitative analysis was conducted using KH Coder, a text-mining tool that integrates content analysis concepts with computational text analysis techniques. The KH Coder is a GUI-based software program developed by Professor Higuchi at Ritsumeikan University, a specialist in social research and quantitative text analysis ²⁵.

A key output of this tool is a co-occurrence network that visualizes word pairs that frequently appear together within the same sentence as linked nodes. This network structure represents the similarity in word occurrence patterns using the Jaccard coefficient ²⁶, which is employed to classify these relationships. The characteristics embedded in textual data can be identified objectively and systematically by applying quantitative text analysis.

In this study, KH Coder was used to analyze the interview transcripts to clarify the relationships among keywords and identify frequently occurring patterns in the participants’ narratives.

3.2.3. Iterative Feedback Process

In this study, an iterative feedback process was conducted with reference to the methodology of Komatsubara et al. ²⁹, to minimize the influence of researcher subjectivity and ensure analytical reliability. Recognizing that human memory is often fragmented and may contain internal inconsistencies, interview data collected from multiple participants were systematically organized. Feedback sessions were repeated with each interviewee to confirm the coherence and accuracy of their interpretations.

Using this process, the study aimed to enhance reliability by achieving a participant consensus on the consistency and structure of the analytical results.

4.1. Overview of the Interview Survey

Interview surveys were conducted with the individuals listed in Table 1. The participants were seven individuals who were instrumental in developing and disseminating the Evacuation Topography Time Map, including the original proponents, researchers, and practitioners.

To ensure the appropriateness of the selected participants, their suitability was cross-validated among interviewees during the study. Additional participants were included when necessary to ensure comprehensiveness and relevance of the data collection process.

Interviews were conducted according to the procedures described in Section 3.1. Based on the participants’ narratives, the interviewer prepared verbatim transcripts for the interviews.

4.2. Results of the Quantitative Text Analysis

The results of the quantitative text analysis are presented in Fig. 5. To enhance interpretability and reduce the potential ambiguity caused by an excessive number of visualized terms, the analysis was limited to words that appeared at least seven times and to relationships with a Jaccard coefficient of 0.2 or higher. The Jaccard coefficient is a statistical measure used to represent the similarity between two sets; values of 0.2 or above are generally interpreted as indicating a strong association (Higuchi ²⁶).

In this study, a morphological analysis was conducted in Japanese, and a co-occurrence network was generated using the KH Coder. Note that the words visualized in the co-occurrence network were translated into English specifically for the purpose of this study; therefore, the English terms displayed in the network do not necessarily represent actual co-occurrences in the original Japanese text.

The co-occurrence network presented in Fig. 5 was further examined using the key word in context concordance function in KH Coder to understand how each extracted term was used in context. Based on these contextual interpretations, the extracted words were organized and grouped into ten categories by the researcher (Fig. 6). The group labels were reviewed based on feedback from the interview participants to confirm the appropriateness of the categorization.

4.3. Results of the SCAT

The analytical procedure is illustrated in Fig. 7. Based on interview transcripts, the researcher segmented the content into meaningful units and assigned labels to each unit. Labels with similar meanings were then integrated and grouped into broader categories.

Consequently, 118 labels were generated and organized into 29 categories. These 29 categories were subsequently treated as “texts” and analyzed using the SCAT method, through which theoretical descriptions were developed. This process led to the extraction of ten theoretical constructs, as summarized in Table 2.

4.4. Feedback to Interview Participants

The researcher provided feedback to the interview participants regarding the results of the quantitative text analysis and SCAT, both of which were based on interview data collected using the principles of disaster ethnography.

This iterative feedback process ensured coherence and consistency of the data, thereby enhancing the analytical rigor and reliability of the findings.

5.1. Commonalities: Present in Both Quantitative Text Analysis and SCAT

The items identified by both analytical methods—quantitative text analysis and SCAT—can be interpreted as terms or themes that frequently appeared during the interviews or were recognized by the participants as particularly important. Items \(⟦ 1⟧\) through \(⟦ 5⟧\) fall under this category.

\(\boldsymbol{⟦ 1⟧}\) Evacuation Topography Time Map is a community-based risk communication program grounded in the experiences and lessons learned from disaster-affected communities and architecture and urban planning expertise, emphasizing communication with local stakeholders.

These findings suggest that the Evacuation Topography Time Map was developed through repeated visits to disaster-affected areas by proponents, who engaged with local communities and sought to incorporate the voices and lessons of those affected. This approach reflects the persistent and reflective effort to explore what could meaningfully be done in the aftermath of disasters.

The workshop was developed by the volunteer division of Nikken Sekkei, an organization with expertise in architecture and urban planning. The procedure was simple and highly visual. Participants used colored pencils and leather cords to mark evacuation routes on blank base maps. A distinctive feature of the program is its emphasis on organizers’ awareness and the importance of communicating with local residents. One participant aptly described the method as “the visualization of unintended information,” highlighting the program’s ability to reveal implicit community knowledge. Among the notable examples extracted from the data is the case where elevational differences, which are often difficult to interpret from flat maps, are represented using a physical model. An architect, who also served as a school board member, initiated this initiative. It is inferred that this example was identified through a co-occurrence analysis with keywords associated with architectural and urban planning expertise, reinforcing the interpretation that the Evacuation Topography Time Map workshop effectively integrates such disciplinary knowledge. These design features are important for evaluating the utility and potential of the Evacuation Topography Time Map.

\(\boldsymbol{⟦ 2⟧}\) Strategic workshop design for linking the Evacuation Topography Time Map to community problem-solving, including disaster preparedness and planner-oriented considerations.

Ushiyama et al. ¹³ and Komura ³⁰ warned that merely conducting a workshop is not inherently meaningful because it may create a false sense of accomplishment without prompting concrete action. However, in the case of the Evacuation Topography Time Map initiative, there are reported examples in which workshop outcomes have been used to implement specific measures such as improving evacuation routes or removing concrete block walls that could hinder evacuation ¹⁷.

As a workshop developed by professionals in architecture and urban planning, the Evacuation Topography Time Map reflects a high level of awareness regarding community development. Consequently, it not only facilitates proactive disaster preparedness measures but also holds the potential to evolve into broader initiatives to solve local issues from multiple perspectives, transcending the conventional boundaries of disaster risk reduction.

\(\boldsymbol{⟦ 3⟧}\) Since the Evacuation Topography Time Map is designed to be inclusive for all generations and can be used by upper-grade elementary school students, it has been widely used as educational material for disaster preparedness.

Although the designation of the target area and selection of the disaster type during the preparatory phase can present certain challenges, the actual implementation process is simple and highly user-friendly. Consequently, the program can be conducted with upper elementary school students and has already been successfully introduced in educational settings. This demonstrates its applicability and effectiveness as a disaster education tool.

However, as discussed in Item \(⟦ 5⟧\) below, the preparatory process, particularly in determining the appropriate geographic scope and disaster scenario, requires careful consideration and creative planning to ensure effectiveness.

\(\boldsymbol{⟦ 4⟧}\) The Evacuation Topography Time Map has gradually gained recognition and expanded through collaborative efforts, receiving high acclaim from various sectors. These collaborations include the using digital technology and arts-based programs for community engagement and education.

A distinguishing feature of the Evacuation Topography Time Map initiative lies in its simple yet refined procedures, allowing flexible integration of various input-output elements in workshop design. This adaptability facilitates diverse collaborations between digital technology and art-based programs. According to the results of the quantitative text analysis and SCAT, the initiative attracted new participants over time, contributing to the expansion of its activities.

Further innovation is anticipated through the continued collaboration among a wide range of stakeholders across various sectors.

\(\boldsymbol{⟦ 5⟧}\) There is a growing need to lower the barriers to implementing Evacuation Topography Time Map workshops, particularly in multi-hazard contexts where the complexity of base map delimitation poses significant challenges.

However, some participants noted difficulties preparing the base map that was used as the foundation for the Evacuation Topography Time Map workshop. This challenge stems from the complexities of defining the target area and selecting a specific hazard scenario, as discussed in the procedure section. Therefore, establishing a system that allows easy access to usable base maps is essential.

The Evacuation Topography Time Map approach is fundamentally based on the assumption of safe zones derived from various types of hazard maps, and it visualizes evacuation routes accordingly. However, as Ushiyama et al. ¹³ highlighted, hazard knowledge is a critical component in considering evacuation and safety strategies. From the perspective of disaster risk reduction, understanding the relationship between hazards and vulnerabilities is essential ³¹. Further collaboration with experts, knowledge networks, and institutional partners in hazard assessment is expected to enhance the depth and applicability of the Evacuation Topography Time Map methodology.

5.2. Differences: Not Identified in Quantitative Text Analysis, Identified in SCAT

Items identified solely through SCAT—but not in the quantitative text analysis—can be interpreted as concepts that, although not frequently mentioned in participant narratives, were given interpretive significance during the theoretical description process. Items \(⟦ 6⟧\) and \(⟦ 7⟧\) fall into this category.

\(\boldsymbol{⟦ 6⟧}\) The NIGECHIZU Research Group, comprising members from government, academia, and industry with a shared interest in the Evacuation Topography Time Map, has been established to advance facilitator development.

Based on the results of the SCAT, the importance of cultivating qualified facilitators for the Evacuation Topography Time Map initiative was highlighted. In response, the NIGECHIZU Research Group established a new certification system titled “Disaster NIGECHIZU Practitioner.” This initiative aims not only to ensure the quality and consistency of workshops but also to strengthen horizontal networks among workshop organizers.

\(\boldsymbol{⟦ 7⟧}\) Considering future societal changes such as population decline, particularly in rural areas, re-examining the role of the Evacuation Topography Time Map in communities where the number of potential evacuees may drastically decrease is necessary.

Comments collected through the Evacuation Topography Time Map Initiative also reflect future social and environmental conditions. A review of the casebook published by the NIGECHIZU Research Group ⁸ reveals that the Evacuation Topography Time Map is often used not only for evacuation planning but also for understanding the local community and addressing a wide range of regional issues.

Although the term Evacuation Topography Time Map intuitively suggests a “map for evacuation,” a deeper examination of its content reveals that it possesses multifaceted utility. Rather than functioning only as a means of escape, it has been employed in various contexts to enhance local knowledge and support community-driven problem-solving efforts.

5.3. Comparison from the Perspectives of “Field,” “Facilitation,” and “Science and Technology”

Based on the framework of “field,” “facilitation,” and “science and technology,” Items ③ and ⑦ are categorized under “field,” Items ②, ⑤, and ⑥ fall under “facilitation,” and Items ① and ④ are classified as “science and technology” (Table 4).

In this case study, several key points were identified from the perspective of the “field,” focusing on how the Evacuation Topography Time Map has been used across various local contexts, as well as how they may be further developed. From the perspective of “facilitation,” the analysis revealed the necessity of strategic program design for effective implementation of the Evacuation Topography Time Map, the difficulties encountered during the design process—such as determining the disaster scenarios and preparing base maps—and the need for initiatives to cultivate capable facilitators. Furthermore, from the perspective of “science and technology,” it was noted that the Evacuation Topography Time Map represents a technology developed in response to local conditions and community voices in disaster-affected areas, and that new possibilities are emerging through collaboration with digital technologies and art-based programs.

7.1. Key Findings of the Study

Semi-structured interviews were conducted with certified “Level 1 Disaster Evacuation Topography Time Map Specialists,” including the original proponents of the Evacuation Topography Time Map and experienced practitioners and researchers who have been deeply and continuously involved in its development and dissemination. Drawing on the methodological framework of disaster ethnography, this study aimed to capture the opinions of experts from multiple perspectives. A mixed-methods approach was adopted, combining quantitative text analysis with the SCAT qualitative analysis technique. Comparing the results of the two methods helped to identify seven key points concerning the current status and challenges of the Evacuation Topography Time Map. Feedback was provided to all interviewees regarding their findings, and a consensus was reached to enhance the reliability and validity of the results. The appropriateness of the number of participants in qualitative interview studies is often assessed based on the concept of “saturation,” which refers to the point at which no new information emerges as additional participants are included. However, clearly demonstrating the achievement of saturation is not always straightforward, and recent discussions have emphasized the importance of “data adequacy” as a more practical and meaningful criterion ³². We considered data adequacy to be ensured when sufficient reliability and validity were confirmed through feedback from each participant and by examining the composition of the interviewees. Additionally, when participants suggested specific individuals for interview, we incorporated these recommendations and expanded the sample accordingly. Thus, we believe that the number of participants should be determined not solely by numerical criteria, but through a flexible design informed by contextual judgment and feedback obtained during the research process.

7.2. Future Directions and Limitations of the Study

This study aimed to clarify the current state and challenges of the Evacuation Topography Time Map by conducting interviews primarily with experienced individuals, such as workshop organizers. However, the perspectives of general users of the Evacuation Topography Time Map were not sufficiently analyzed.

In future research, interview surveys, questionnaire-based studies, and workshops with beginners, intermediate users, and individuals from diverse backgrounds are expected to reveal the multifaceted value of the Evacuation Topography Time Map. Furthermore, applying the analytical process proposed in this study to other disaster-related programs will enable a clear understanding of their respective characteristics and challenges. Moreover, a comparative analysis across different programs may contribute to improving each initiative and to the exploration of more effective approaches to disaster education.