This special issue presents a study on atoll countries vulnerable to climate change. The average elevation of these countries is only approximately 2 m above sea level. Therefore, as sea levels rise, the only possible adaptation measures would be to build large-scale infrastructure, such as artificial islands, or to migrate to other countries. This study focuses on three of the world’s four atoll countries: the Maldives, the Marshall Islands, and Kiribati. We analyzed residents’ attitudes toward and the costs associated with artificial island construction and land reclamation.

In the Maldives, where the construction of artificial islands is already underway, we examined the motivations for migration to these islands and the satisfaction levels after migration. The findings revealed that those who migrated from Malé, the capital, and a densely populated area, were more satisfied with their lives after migration, whereas those who migrated from other atolls reported lower levels of satisfaction. In addition, high costs of living, rent, and housing were barriers to migration.

In the Marshall Islands and Kiribati, which do not have artificial islands such as those in the Maldives, we conducted a causal analysis of religious, cultural, and educational factors affecting residents’ perceptions of climate change. In both countries, education has a universal impact on climate change awareness, however, the manner in which it affects people varies between the two. In the Marshall Islands, education-related variables are relatively isolated, whereas in Kiribati, variables related to education, religion, and culture form a complex network that influences each other.

A survey of college students in the Marshall Islands revealed that young people were highly aware of climate change and strongly desired to migrate. However, many expressed a desire to preserve Marshallese culture and way of life, and opinions on the construction of artificial islands were divided.

An analysis of the cost-effectiveness of adaptation measures, such as building protective infrastructure and raising land to address the vulnerability of coastal areas in the Marshall Islands, revealed that the amount of funding required to implement effective adaptation measures would far exceed the country’s economic strength. Moreover, the cost of major protective measures would be several to ten times the GDP. Despite assessing from a disaster risk reduction perspective, many adaptation measures were found to have a cost-benefit ratio of less than one.

The Maldivian government has reclaimed Hulhumalé, an artificial island, to reduce the congestion in the capital city Malé and address the rising sea levels due to climate change. The population in Hulhumalé consists mainly of migrants from Malé and other atolls. This study identifies the differences between migrants from Malé and other atolls in terms of attributes such as gender, age, previous place of residents, etc., life events that triggered migration, life satisfaction, and their motivation to migrate. An anonymous online survey was conducted in 2023–2024, and 252 responses were received from the residents of Hulhumalé. Among them, 74% were from Malé and 18% from other atolls. The gender distribution of migrants from Malé was almost balanced, with a higher proportion of men from other atolls. The availability of housing in Hulhumalé was an important life event that triggered migration for those from Malé. They reported high levels of post-migration life satisfaction and a strong intention to settle in Hulhumalé. Conversely, migrants from other atolls reported lower levels of post-migration life satisfaction and a lower intention to settle than those from Malé. Pre-migration expectations of migrants from Malé included new, clean housing, a quiet and pollution-free environment, and affordable living and housing costs. In contrast, migrants from other atolls prioritized job, education, healthcare, infrastructure, and transport accessibility. These results suggest that in order to integrate migrants from other atolls with those from Malé, apart from the provision of housing, comprehensive social development in Hulhumalé is needed.

The voluntary migration to Hulhumalé, an artificial island in the Maldives, presents a unique context for studying the impacts of internal migration on life satisfaction. This study aims to identify measures that the Maldivian government could implement to mitigate migration impacts and enhance life satisfaction in Hulhumalé. A recent survey conducted in the four atolls with Maldives National University (MNU) campuses—Kulhudhuffushi, Gan, Hithadhoo, and Thinadhoo—yielded 398 responses, proportionate to their populations. The questionnaire, administered in person by MNU enumerators between December 2023 and January 2024, mirrored the 2022 Hulhumalé survey, focusing on demographics, migration attitudes, and expectations of Hulhumalé. A 2022 survey of Hulhumalé residents revealed disparities in life satisfaction between those who relocated from Malé and those from other atolls. The results from 2024 survey highlight the fact that good facilities, including dining, shopping, sports, and parks, are highly regarded factors driving migration, albeit with the trade-offs of high living expenses, rent, and other housing costs. High-quality primary and higher education, along with access to medical care, were also positively rated. However, aspects related to disaster resilience and safety against sea level rise due to climate change were rated lower.

This study examines the causal relationships between factors related to religion, culture, and education that influence perceptions about climate change in the Republic of the Marshall Islands (RMI) and Kiribati. Building on previous research that identified these three domains as important, this study utilizes Bayesian networks to uncover deeper connections between specific variables. Questionnaire data were collected from university students in both countries and analyzed using the R package “bnlearn” to construct Bayesian networks. Key variables from each domain were selected based on prior structural equation modeling studies. The resulting networks revealed complex interconnections between religion, culture, and education in shaping climate change perceptions. While some similarities exist between the two countries, notable differences emerged in the relationships between variables. In the RMI, certain climate perception variables appeared more isolated, while in Kiribati they showed broader connections to religious and cultural factors. These findings suggest that the underlying structure of influences on climate change perceptions may differ between the two island nations, despite surface similarities. The Bayesian network approach provides new insights into the causal pathways between domains that were not apparent in previous analyses. This deeper understanding of how religion, culture, and education interact to shape climate perspectives can inform more targeted and effective climate change communication and education efforts in the Pacific island communities.

In this study, we aimed to investigate the prospect of constructing artificial islands as a climate change adaptation strategy for the Marshall Islands. A survey of Marshallese college students revealed a high level of concern about climate change and openness to emigration, particularly among younger people. However, there was also a strong desire to preserve Marshallese culture and way of life. The concept of artificial islands as a way to enable the “right to stay” in the Marshall Islands received mixed reactions. While some see it as a promising solution, others have concerns about safety, environmental impact, and maintaining their traditional lifestyle. We concluded that artificial islands, if carefully planned and implemented, could be part of a comprehensive adaptation strategy that includes international financial assistance, vocational training, and efforts to secure rights for Marshallese emigrants. Further research is needed to assess the feasibility and impacts of artificial islands, and the international community has a role to play in supporting such efforts.

Climate change poses an existential threat to small island developing states, particularly atoll nations like the Republic of the Marshall Islands (RMI). This study examines the economic and financial challenges of implementing climate change adaptation measures in these vulnerable countries. Through a comprehensive literature review and a case study of the RMI, the costs and feasibility of various adaptation strategies, including coastal protection, land raising, and migration, were analyzed. Findings reveal that the financial requirements for effective adaptation far exceed the economic capacities of the RMI. Even basic protective measures require investments multiple times the country’s gross domestic product. The benefit-cost ratios of adaptation projects fall below 1 when evaluated solely on disaster risk reduction, highlighting the need for a paradigm shift in assessing adaptation investments in highly vulnerable nations. This study underscores the critical importance of international climate finance and support. While the RMI has received significant climate development finance, the scale of required adaptation measures far surpasses this level of assistance. The key challenges included not only debt sustainability concerns but also traditional land tenure systems, ecological impacts, and the limitations of conventional cost-benefit analyses in the context of national survival. This study offers valuable insights for policymakers, international organizations, and researchers working on climate resilience in vulnerable coastal nations.

After the 1923 Great Kanto Earthquake, Japan received international humanitarian aid from many countries, most notably from the U.S. The U.S. provided an “unprecedented deployment of humanitarian aid,” which was unusual for conventional U.S. international humanitarian assistance. The U.S. aimed to improve the U.S.–Japan relationship, seizing this disaster assistance as an opportunity. In various ways, Japan expressed gratitude to the U.S., including through 744 thank-you letters from Japanese students, confirmed by the authors for the first time. The authors analyzed these letters and discovered that they not only expressed the students’ gratitude for the U.S. support but also their wish to promote friendship between Japan and the U.S. and to achieve world peace. The U.S. aid following the Great Kanto Earthquake and the Japanese students’ thank-you letters exemplify “disaster diplomacy.” These letters indicate that disaster diplomacy involves not only direct disaster relief, but also efforts to strengthen friendly relations between people of the two nations.

As global demographic trends shift toward an increasingly aging population, disaster preparedness for older adults has become a major public health concern. This study comprehensively analyzed community-based disaster preparedness targeting older adults in Dusit District, Bangkok, Thailand. The primary objective was to identify and address the specific vulnerabilities of older adults, such as chronic illnesses, mobility impairments, and sensory decline, which amplify their susceptibility during disaster events. Conducted between October 2021 and September 2023, this study employed a cross-sectional descriptive design. A total of 500 participants aged 60 years and above were recruited. This study evaluates disaster preparedness in four critical stages: emergency response, prevention and mitigation, rehabilitation, and preparedness. The findings suggest that although preparedness measures are moderately implemented, the provision of customized support and the development of age-appropriate shelters for older individuals are of paramount importance. Moreover, this study underscores the essential role of community involvement and interagency coordination in enhancing disaster resilience. Therefore, a holistic and integrative approach is required to advance disaster preparedness for older adults. This approach should include personalized support systems, optimized resource allocation, and specialized training programs. Enhancing community disaster preparedness mitigates vulnerability among older adults, thereby improving their safety and overall well-being in disaster scenarios.

Information and communication technology (ICT) development has changed human activity and behavior, including spatial choices for activity space. This phenomenon contributed to disaster risk reduction because similar dependent variables related to activity space and place were represented in land use. In disasters, land use can affect the disaster risk level. This study explored the contribution and correlation patterns of ICT development to disaster risk reduction efforts from a spatial perspective. This study used 12,155 articles from the Scopus database as a data study analyzed using systematic review and meta-analysis. This study found that ICT development had a possibility spatial contribution to disaster risk reduction indirectly through virtual space in two forms: activity location efficiency and changes in land use. ICT development and its virtual space contributed to changing vulnerability, hazard, and capacity in the face of disasters.