This special issue summarizes some of the findings of the first half of our international joint research between Japan, Thailand, and Vietnam. This collaborative research is based on the framework of the e-ASIA Joint Research Program (e-ASIA JRP) and lasts for three years. Rainfall-induced landslides are a common disaster in many Asian countries. Our goal is to develop a practical method for landslide susceptibility mapping so that there are fewer landslide disasters in the future.

The e-ASIA JRP is an international joint initiative of public funding organizations in the East Asia Summit member countries. Based on the co-funding mechanism, support for the research teams is received from the funding organizations in their respective countries. Since 2019, the Japanese, Thai, and Vietnamese teams have been supported by the Japan Science and Technology Agency (JST), the National Science and Technology Development Agency of Thailand (NSTDA), and the Ministry of Science and Technology of Vietnam (MOST), respectively.

In the first half of our project, we completed the basic steps for developing the system. In this special issue, we are proud to present some of our achievements, including studies on slope failure analysis, landslide prevention works, meteorological observations, landslide monitoring, statistical or wide-area risk evaluations, mathematical models, and flash flood control. In addition to the above, we also present other valuable research achievements that related members have provided to help ensure the achievement of our goals. In total, 20 papers are published here. We believe that our comprehensive research activities will dramatically increase future landslide disaster mitigation, especially in monsoon Asia, and will strongly augment the roadmap for achieving the global Sustainable Development Goals (SDGs) as a common desire of humanity.

Natural hazards continue to be an increasing challenge to societies around the world, with many societies being impacted by multiple types of hazard events. To reduce the impact of these hazards, we must not only quantify the hazard and risk associated with multi-hazard events but also understand the uncertainty associated with these events. Resilience can only be improved by considering all these factors. Multi-hazard and risk-modeling approaches are receiving increasing attention globally; however, the challenges of assessing uncertainty in both single- and multi-hazard risks are considerable. Without a clear understanding of the risks and their uncertainties, measures to mitigate these risks and to increase resilience face difficult decisions. In the present Special Issue, we have five papers and one report on the Tokyo Metropolitan Resilience Project: Interdisciplinary and Industry-Academia Collaboration Research for Enhancing Social Resilience to Natural Disasters in the Tokyo Metropolitan Area –DEKATSU Activity–, Multi-Data Integration System to Capture Detailed Strong Ground Motion in the Tokyo Metropolitan Area, Development of the Training Tool “KUG” for Temporary Lodging Facilities and Companies for Stranded Commuters, Development of Matching Modeling for Human Resource Allocation of Shelter Management by the Set Theory, Time-Cost Estimation for Early Disaster Damage Assessment Methods, Depending on Affected Area, and A Report of the Questionnaire Survey on Awareness of COVID-19 and Shelters.

As rainfalls exceeding the designed level have increased, so has damage associated with pluvial flooding. Typhoon Hagibis, which swept Japan in 2019, left 140 municipalities in 15 prefectures scarred from flooding. The sewage networks damaged by the typhoon affected civic life by paralyzing urban functions, raising concerns in urban flood risk and management. Increases in heavy rainfall events associated with global climate change are expected to increase damage from pluvial flooding, thereby necessitating reviews of current urban flood risk management for the purpose of making further improvements against future threats. As we enter an era of frequent urban flooding, it is vitally important that we prepare for urban flood risk management by sharing scientific and technological knowledge among academics, private companies, and administrators.

In this context, the current issue is a compilation of contemporary research studies in academia, technological advances in private companies, and practical applications in public administrations in Japan. The works include: the application of urban flood modeling in safe evacuation strategies, the assessment of economic loss, and the impact of climate change; state of the art technologies for urban flood management with the Internet of Things (IoT) and Internet Communication Technology (ICT), Unmanned Aerial Vehicles (UAV), and the next generation of weather radars; and best practices for flood countermeasures, based on knowledge and experience from historical flooding and applied in prefectural governments and local municipalities.

We are grateful to all the authors and reviewers who contributed to this special issue, and we hope that it may internationally enhance knowledge-exchange in preparation for growing urban flood risks.

This special issue of the Journal of Disaster Research focuses on disaster storytelling, an emerging concept in disaster risk reduction. Despite its popularity and importance, its individual practices and activities, as they tend to be spontaneous and local, have received only limited attention from academia and have not been given special attention by the disaster research community.

The papers included in this volume contain multi-dimensional discussions on disaster storytelling, including ones that focus on concepts and theory, the functions of disaster museums, tourism, local communities, UNESCO geoparks, disaster ruins and heritage, art and culture, and disaster education. The readers can understand the variety of disaster storytelling activities that exist around the world and their potential contribution to building resilience in society. We believe this issue is the first academic publication to focus specifically on disaster storytelling, and we hope that this volume contributes to creating scientific value, attracts additional attention, and develops further discussions about the role of disaster storytelling within the disaster research community. We also believe that such discussions will help various individuals and entities reidentify the importance and significance of their activities of disaster storytelling as well as contribute to continuing or strengthening such activities around the world.

All of the contributors to this issue participated in the International Forum on Telling Live Lessons from Disasters (TeLL-Net Forum), held January 24–26, 2020 in Kobe, Japan. The articles included in this issue include ones that were inspired by discussions during and after the forum. Readers interested in this forum can obtain the official report from the TeLL-Net website: https://tell-net.jp/forum2020/pdf/00_Tell_Net2020_Report_print.pdf.

We, the editorial board of this special issue, would like to express our deep appreciation to the Hyogo Earthquake Memorial 21st Century Research Institute for the research grant on disaster storytelling. We also would like to express our gratitude to the Kobe Machizukuri Rokko Island Fund Charitable Trust (Tokyo, Japan) and AIG Institute (Osaka, Japan) for financial contributions that supported the publication of the issue.

COVID-2019 was first identified in Wuhan, China, at the end of 2019, and from there it spread worldwide. Due to this worldwide distribution of COVID-19 cases, the WHO declared a COVID-19 pandemic. The pathogen of COVID-19, a novel corona virus, resembles SARS-CoV, the pathogen of SARS (severe acute respiratory syndrome, a pandemic in 2003), so the International Committee on Taxonomy Virology named it SARS-CoV-2. However, COVID-19 is a different disease from SARS, and should be controlled to the extent possible with the effective vaccines and therapeutic medicines.

Although one year has passed since the first appearance of the disease, the number of COVID-19 cases continues to increase, and the pandemic is now in its third large wave. It is thought that it will be difficult to eradicate the disease completely, because SARS-CoV-2 is possible to invade and live in various host animals in addition to humans.

During this pandemic, the JDR has put together the special issue “COVID-19 and Historical Pandemics.” Because there have been many pandemics that have transformed society in various ways, the special issue includes historical pandemics in addition to COVID-19. The manuscripts in this issue include various subjects related to COVID-19, including methods of analyzing the pandemic, suggestions for countermeasures against it, methods of prevention and epidemiological reviews, among others.

The WHO has released a large volume of pandemic information on an ongoing basis, including its “COVID-19 Weekly Epidemiological Update.” In the weekly edition of December 27, it reported the cumulative number of cases and percentages of the global total from around the world: the Americas 34,403,371 (43%), Europe 25,271 (31%), Africa 1,831,227 (2%), and the Western Pacific 1.059,751 (1%). It is notable that 74% of cumulative global total number of cases have been reported in the Americas and Europe, where most developed countries are included, whereas the numbers in Africa, which includes many developing countries, and the Western Pacific region, which includes Thailand, the Philippines, Vietnam, and Malaysia in addition to Japan and China, are 2% and 1%, respectively. This indicates that the COVID-19 pandemic is a different from previous epidemics caused by other infectious diseases.

As the pandemic spreads, the JDR plans to edit Part 2 of this COVID-19 special issue.

The Sixth JDR Award ceremony was held online due to COVID-19 on October 6, 2020 and a prize were given to Professor Masato Iguchi, Disaster Prevention Research Institute (DPRI), Kyoto University, Japan. We congratulate the winner and sincerely wish for future success.

It is our great pleasures to present the sixth JDR Award to Prof. Masato Iguchi. Prof. Iguchi, as the top guest editor, published two JDR special issues entitled “Integrated Study on Mitigation of Multimodal disasters caused by Ejection of Volcanic Products.” These special issues, vol.11, no.1 in 2016 and vol.14, no.1 in 2019, were results of a project (2013–2018) of the Science and Technology Research Partnership for Sustainable Development (SATREPS). The second special issue set a record for the highest annual download. In addition, he was the first author or co-author of 11 papers published by JDR in 2019.

Professor Iguchi, as one of most recognized volcanologists in the world, has been leading observation research of active volcanoes as the Director of the Sakurajima Volcano Research Center of Kyoto University’s Disaster Prevention Research Institute. He has promoted geophysical research on volcanic activity not only in Japan but also in Indonesia, evaluating volcanic activity by incorporating the results of material science and demonstrating the effectiveness of long-term, multi-item observations in those processes. He has made a significant contribution to the promotion of Indonesian volcano research, taking over the strong will of former Kyoto University professors, and his contributions have culminated in the aforementioned two special issues.

On behalf of the JDR editorial board, I wish to thank Prof. Iguchi for his efforts and to congratulate him as the winner of the sixth JDR Award.

A volcanic eruption is a phenomenon in which ballistic bombs, lapilli, volcanic ash, lava, and gas are discharged. Volcanic ash and gas are carried by the wind, and pyroclastic flows and lava flows are carried away by the force of gravity. These cause disasters of various forms in the areas around volcanoes, sometimes far from eruptive center. Accordingly, volcanic countries, particularly Asian countries such as Japan, Indonesia, and the Philippines, have been the scenes of volcanic disasters. We conducted the research project “Integrated study on mitigation of multimodal disasters caused by the ejection of volcanic products” with the Center for Volcanology and Geological Hazard Mitigation and other institutes in Indonesia under the SATREPS project from FY2013 to 2018. The aim of the project was to advance volcanic hazard mitigation, and I served as the guest editor of “Special Issue on Integrated Study on Mitigation of Multimodal Disasters Caused by Ejection of Volcanic Products” (2016) and “Special Issue on Integrated Study on Mitigation of Multimodal Disasters Caused by Ejection of Volcanic Products: Part 2” (2019) of the Journal of Disaster Research. The articles in the Special Issues have been downloaded by many researchers. The Special Issues cover many topics related to volcanic disasters, but the main theme is how to forecast real-time volcanic hazards using data monitoring, since it is this monitoring that triggers the issuing of warnings.

I have studied the volcanic activity of Sakurajima, the most active volcano in Japan, for 40 years, primarily to forecast its eruptions. Forecasting the eruptions is not as important as forecasting the hazards and risks posed by volcanic actions. Research done on the mitigation of the volcanic hazards of Sakurajima as well as Indonesian volcanoes has been enhanced by interaction. The cumulative volume of magma stored in the past 100 years indicates that Sakurajima has the potential for a large-scale eruption (VEI > 4). An eruption and its dispersal of volcanic ash in particular would cause a variety of disasters over a wide area, as described in the other issues of Journal of Disaster Research. I hope that the research results will be utilized for hazard mitigation in the event of future large-scale eruptions. The research could be advanced through collaboration with studies aimed at the enhancement of resilience and recovery.

The World Bosai Forum/International Disaster Risk Conference@Sendai 2019 (WBF2019) held in November 2019 in Sendai City, Japan, was successful in bringing together actors from multiple sectors to advance the goals of disaster risk reduction (DRR). We would like to take this opportunity to express our heartfelt gratitude to all those who participated in the sessions, exhibitions, poster sessions, and mini-presentations, as well as to the many local people who came to the event.

According to the World Bosai Forum [1], 871 participants from 38 countries attended the WBF2019 which included 50 oral sessions, 3 keynote speeches, 47 poster sessions, 33 mini-presentations, and 14 exhibition booths, which contributed to deepening the discussion and promotion of the “Sendai Framework for Disaster Risk Reduction, 2015–2030” (SFDRR) and in particular progress towards the achievement of Global Target E, to substantially increase the number of countries with national and local disaster risk reduction strategies by 2020. Including lessons learned from the Great East Japan Earthquake and Tsunami, local knowledge and solutions towards advancing BOSAI were actively shared and discussed among the participants who joined this global forum, from various organizations and sectors. In particular, there were many sessions in which young people and private companies played a key role.

The guest editors are pleased to publish this special issue of the Journal of Disaster Research, which is comprised of 13 articles sharing the research advancements presented at the WBF2019. We hope that this special issue on the WBF2019 will contribute to the literature on disaster science and further advances in disaster risk reduction.

The Global Centre for Disaster Statistics (GCDS) at the International Research Institute of Disaster Science (IRIDeS) at Tohoku University was established in April 2015 to support the monitoring of the global targets of the Sendai Framework for Disaster Risk Reduction 2015–2030 (SFDRR). The GCDS, in partnership with the United Nations Development Programme (UNDP), is to provide support for National Disaster Management Offices (NDMOs) to build capacity in developing national disaster loss and damage statistics, an essential tool used in monitoring and policy making for the reduction of disaster risk. Since its establishment, the GCDS has been contributing to the implementation of the SFDRR.

In 2019, the GCDS participated in the Sendai Framework Voluntary Commitments (SFVCs), launched by the United Nations Office for Disaster Risk Reduction (UNDRR). Although the information regarding the activities of the GCDS is described in detail in the first Synthesis and Analysis Report of the SFVC [1], one of the activities committed to in its SFVC is to publish special issues of the Journal of Disaster Research as a contribution to the development of disaster statistics. The guest editors are pleased to publish the third special issue, which contains valuable academic articles closely related to the activities of the GCDS.

We hope that this special issue on the Development of Disaster Statistics makes a significant contribution to the literature on disaster statistics and accelerates its development.

We are very pleased to publish the Special Issue on NIED Frontier Research on Science and Technology for Disaster Risk Reduction and Resilience 2020. There are nine papers in this issue.

The first two papers concern hazard and risk information systems: Sano et al. constructed a real-time risk information map for flood and landslide disasters, and Hirashima et al. created an alert system for snow removal from rooftops. These systems are already in use on the NIED website. The next three papers are case studies of recent storm disasters in Japan and the United States: Cui et al. analyzed the time variation in the distribution of damage reports in the headquarters for heavy-rainfall disaster control in Fukuoka, Shakti et al. studied flood disasters caused by Typhoon Hagibis (2019), and Iizuka and Sakai conducted a meteorological analysis of Hurricane Harvey (2017). Regarding volcanic disasters, Tanada and Nakamura reported the results of an electromagnetic survey of Mt. Nasudake.

This special issue also includes three papers on large-scale model experimentation: Danjo and Ishizawa studied the rainfall infiltration process using NIED’s Large-Scale Rainfall Simulator, Kawamata and Nakazawa conducted experiments concerning liquefaction, and Nakazawa et al. reported the results of experiments on seismic retrofits for road embankments. The experiments used E-Defense, the world’s largest three-dimensional shaking table.

We hope this issue will provide useful information for all readers studying natural disasters.

This special issue summarizes the main results of the first two years of the Science and Technology Research Partnership for Sustainable Development (SATREPS) project, which is supported by the Japan Science and Technology Agency (JST) and the Japan International Cooperation Agency (JICA). SATREPS has provided excellent opportunities for our joint research team from Thailand and Japan to work in close coordination on challenging multidisciplinary issues.

The Area-BCM for the Enhancement of Resilience of Industrial Complexes in Thailand project was started in 2018. Its scope includes the impacts of urban flooding disasters in Bangkok and its surrounding areas where socio-economic functionalities have been concentrated, as well as chain repercussions of disaster impacts, spread through global supply chains, in important production and logistics facilities in Thailand. Our high-level project targets are based on the Sendai Framework for Disaster Risk Reduction (SFDRR) 2015–2030 as well as Sustainable Development Goals (SDGs), especially #11 (Sustainable Cities and Communities), #8 (Decent Work and Economic Growth), and #13 (Climate Action).

This issue contains interim research results from our project mainly led by members from Thailand with regional aspects of our project site. However, we plan to release another special issue by the end of our project that will include more generalized concepts and frameworks that can be applicable to other regions or countries, including Japan.

As we take a multidisciplinary approach that includes science and technology, life and well-being science, and social science, our main objective in featuring this special issue is to make our interim research results known to other researchers and practitioners in related fields. We do this in order to get opinions and suggestions from different perspectives so that these may be reflected in the directions our research takes during the remainder of our project term.

Finally, I am truly grateful for the authors’ insightful contributions and the referees’ acute professional suggestions, which together make this JDR special issue a valuable contribution to making our society more resilient to future disasters.

This special issue summarizes the main results of the latter half of a five-year project called SATREPS (Science and Technology Research Partnership for Sustainable Development) supported by Japan International Cooperation Agency (JICA) and Japan Science and Technology Agency (JST). The project title is “Development of a Comprehensive Disaster Resilience System and Collaboration Platform in Myanmar” and it is the first SATREPS project adopted in Myanmar. Yangon Technological University (YTU) is a major counterpart organization and both national and local governmental organizations are working together as strategic partners.

In the first half of the project, a database was constructed, composed of important data for assessing urban safety and disaster risk, such as the ground properties, and distribution of buildings, people, and traffic. Using the database, city development model and evaluation models for flood and earthquake risks were developed.

In the latter half of the project, combining these two evaluation models, a system was developed for discussing future damage differences due to different urban plans and countermeasures. Furthermore, regarding flood, near-real-time flood inundation simulation system was developed. Related to earthquake disaster, a support system was developed for implementation of efficient countermeasures for both pre- and post-disaster. For infrastructure maintenance, performance monitoring and maintenance methods were proposed. Finally, in order to continue research activities and promote a continuous utilization of project results, a consortium scheme in which industry, government, and academia can work together has been created.

We hope that our SATREPS project activities can contribute to proper urban development and improvement of disaster management issues not only in Myanmar but also in other Asian countries.

The Earthquake and Volcano Hazards Observation and Research Program (2014–2018) carried out comprehensive research to mitigate disasters related to earthquakes and volcanic eruptions. The program selected multidisciplinary research in which earth scientists who study the processes of earthquake generation and volcanic eruptions, historians, archaeologists, human and social scientists, and engineers were all involved. The program aimed to collect pre-instrumental and pre-historical earthquake and volcanic data to understand earthquake and volcano disasters, to find risk evaluation techniques, and to evaluate disaster response and preparedness. Active collaborations between researchers from different science fields inspired new ideas and have driven various research in the program. New findings from the program have also created international collaborations and recognitions. Most of the results and new findings in the program have already been published in various internationally recognized journals and have greatly influenced scientific communities.

We believe that it is important to compile our findings from the last five years of the program and to publish the essence of our findings and published papers in this special issue. We hope that this special issue will be of value to researchers who are interested in multidisciplinary studies of mitigation of disasters such as earthquakes, volcanic eruptions, and related phenomena.

The National Research Institute for Earth Science and Disaster Resilience (NIED) is working on three tasks: predicting disasters, preventing damage, and realizing speedy reconstruction and recovery efforts in the event of natural disasters such as earthquakes, tsunamis, volcanic eruptions, landslides, torrential rains, blizzards, and ice storms.

In the last three years of the NIED’s fourth mid/long term plan period, which began in 2016, natural disasters have occurred every year, including earthquake disasters such as the 2016 Kumamoto earthquake (M7.3) and the 2018 Iburi, Hokkaido, earthquake (M7.1). Disasters of the rainfall include the heavy rainfall in the northern Kyushu (Fukuoka and Oita) in July 2017, the heavy rain event in southwestern Japan in July 2018, the rainfall in northern Kyushu (Saga) in August 2019, and the heavy rainfall in Kanto and Tohoku in October 2019. There were also other disasters: an avalanche accident on Nasudake in 2017 and a phreatic eruption of Kusatsu-Shiranesan in 2018.

Due to the above-mentioned very frequent occurrence of such natural disasters on the Japanese islands, our institute has conducted several research projects to mitigate the damage from such disasters and to accelerate the recovery from them. As the third NIED special issue in the Journal of Disaster Research, several related research results were presented such as those on seismic disasters (Wakai et al., Nakazawa et al., and Ohsumi et al.), those on climatic disasters (Nakamura, and Ishizawa and Danjo), and those of their integrated researches for disaster risk reduction (Cui et al. and Nakajima et al.).

Although the achievements detailed in these papers are the results of individual research, the NIED hopes that these results as a whole will be fully utilized to promote science and technology for disaster risk reduction and resilience. The NIED hopes that this special issue awakens the readers’ interest in new research and, of course, creates an opportunity for further collaborative works with us.

As global sea levels continue to rise, atoll countries—facing persistent and imminent risk—are expected to become source nations of climate migrants in the foreseeable future. This special issue features 10 academic articles, which examine if residents in Pacific atoll countries were, are, or will be ready to re-establish their livelihoods after relocation.

The topic of migration is akin to a kaleidoscope, with continuously evolving shapes and colors, necessitating a broad spectrum of approaches across various disciplines. The authors of these articles thus examined the topic through mathematics, civil engineering, cultural and disaster studies, economics, education, geography, international relations, language, law, sociology and politics. The methodologies applied range from policy analysis to structural equation modeling.

Migration driven by climate change takes place gradually, even over a few decades. Unlike forced migration due to causes such as war and conflict, future climate migrants have the short-term advantage of time to ready themselves for displacement from their homeland. Preparation prior to relocation may include enhancing one’s language or vocational skills.

One of the focal points of this special issue is therefore the preparedness of migrants, both past and future. Case studies were carried out across Fiji, Kiribati, the Marshall Islands, Micronesia, and the United States.

We also considered how migrants are received following resettlement, both in terms of legal instruments and assistance given by the public and private sectors. Case studies conducted in Austria and the United States address this aspect.

Yet another focus is to identify prevailing factors through which people develop their perceptions of climate change and its implications, for such perceptions are a driving force for migration. Case studies in Kiribati and the Marshall Islands contribute to this understanding.

We hope this special issue sharpens the vision of climate change and migration, and serves as a stepping stone for further research in the field.

Since the start of the 21st century, major disasters, such as the 2004 Indian Ocean Tsunami and the 2011 Great East Japan Earthquake, have caused tremendous damage. The scope of the impact has spread across borders because global chains and the like have diversified. Consequently, disaster prevention and mitigation for reduction is now an important issue in the international community. To advance disaster reduction, it has been necessary to combine the humanities and social sciences with medical science and natural sciences as well, and Tohoku University has become the base of disaster prevention. What activities have begun, and for what purpose? I would like to find out and deepen my interest through this mini special feature.

The first part gives the background and objectives of the world’s top research cluster for disaster science. The second part presents survival study, or how to protect oneself from disasters such as tsunamis. Survival study is highly unique to this cluster. Reclassifying is proposed to compile the causes of death indicated by autopsy and systematizing deaths in the event of a disaster. Next, efforts in the humanities and social sciences to preserve the folk performing arts left in the community are presented. It has been pointed out that once local communities and connections are lost in disasters and its recovery faces more difficulty.

A year has passed since the first special issue on the development of disaster statistics was published in the Journal of Disaster Research. The Global Centre for Disaster Statistics (GCDS) at Tohoku University is steadily making progress as well. The GCDS now participates in Sendai Framework Voluntary Commitments (SFVC), which was launched by the United Nations Office for Disaster Risk Reduction (UNDRR). In addition, the GCDS has committed to publishing this special issue of the Journal of Disaster Research toward the development of disaster statistics. Needless to say, the publication of the special issue itself has a positive impact on accelerating research activity at the GCDS.

The guest editors are pleased to publish valuable academic articles that are closely related to the activities of the GCDS, thus contributing to the development of disaster statistics. In this second issue, there seem to be two main categories of research questions: “development of the existing disciplined-based research” and “analyzing various issues by means of questionnaire surveys.” Under the first category, by means of disaster statistics, two disciplines are covered: river engineering and international studies. The large number of studies based on questionnaire surveys act as an excellent reminder of the effectiveness of such a survey as a methodology for disaster statistics.

Last but not least, we hope that this second special issue on the development of disaster statistics will also contribute to the literature on disaster statistics and accelerate its development.

In 2018, Japan not only had an abnormally hot summer, but also experienced successive disasters, including the Northern Osaka Earthquake, the Western Japan Heavy Rain, Typhoon No. 21, the Hokkaido Mid Iburi Earthquake, and Typhoon No. 24. In particular, the record-breaking heavy rains continued in a large area of Western Japan from June 28 to July 4, due to the storm front and Typhoon No. 7. The amount of rainfall totaled over 1,800 mm in the Shikoku Region and 1,200 mm in the Tokai Region. The quantity of rain that fell within 48 and 72 hours in both the Chugoku and Kinki Regions, as well as many other areas, was the highest rainfall ever recorded. A special warning regarding heavy rain was issued in 10 prefectures and every kind of disaster that Japan had experienced recently occurred in various locations. As of August 21, a report from Disaster Management Section, Cabinet Office indicated 221 deaths, 9 missing persons, 68 severely injured persons, 319 slightly injured persons, 3 persons with an unknown level of injury, 6,206 destroyed homes, 9,764 severely-damaged homes, 3,765 partially-destroyed homes, 9,006 homes with flooding above the first-floor level, and 20,086 houses with flooding below the first-floor level.

During this large-scale disaster, which was named the Western Japan Heavy Rain, the Disaster Relief Act was applied to 110 municipalities and JDR decided to issue a special edition to address issues pertinent to this specific disaster event. Paper submissions were requested that not only comprised demonstrative researches on hazard and damage characteristics, methods of evacuation, and features of disaster response, but also included introductions of best practices, which were conducted in various fields and prompted diverse collaboration to develop and establish measures to mediate the effect of the future Nankai Trough Earthquake, as well as problems and solutions to successfully realize diverse collaboration. In response to the call for papers for the special issue, nine researches were submitted and six were accepted following a strict review process. To address the category of hazard characteristics analyses, two papers analyzing the characteristics of the flooding resulting from the Western Japan Heavy Rain and one paper comprising an analysis of landslide disasters were accepted. In the category of disaster response, one paper focusing on the use of SNS and two papers regarding the elderly were accepted. It would be our sincere pleasure if this special issue could contribute to future reductions in damage resulting from natural disasters.

The phreatic eruption of the Ontake volcano in 2014 reminded us that even moderately active volcanoes, most of which are tourist attractions in Japan, can sometimes exhibit unpredictable and hazardous behaviors, taking away the lives of those who do not fully recognize their threat. With this adding momentum, the Japanese people want volcanology and its applications to be developed to further improve the precision of volcanic eruption alerts. To meet this expectation, a comprehensive program, the “Integrated program for next-generation volcano research and human resource development,” sponsored by the Ministry of Education, Culture, Sports, Science and Technology, was started in November 2016 on a 10-years plan. The most stunning aspect of this program is the integration of (1) a research project and (2) a human resource development program to mitigate volcanic disasters in Japan from long-term point of view. Both of these are collaboratively supported by many researchers from almost all Japanese universities and national institutions related to volcanology. This special issue compiles several topics in this research project to demonstrate its present stage of development and to indicate its anticipated future destination. The target of the research project is to develop, using multi-disciplinary scientific methods, new ways of evaluating volcanic hazards. Specifically, four research groups jointly (A) construct a data archive and exchange system connecting all Japanese volcanologists, (B) develop new geophysical and geochemical observation techniques and methods of analyzing data, (C) evolve methods of predicting volcanic eruptions based on eruption history from precise geological survey and numerical simulations, and (D) propose the provision of technologies for volcanic disasters. We hope that this program will greatly help to mitigate volcanic disasters in Japan, and we will strive to realize this through the research project.

The 2011 Great East Japan Earthquake and Tsunami disaster taught us many lessons. Many new findings, insights, and suggestions have been made and implemented in damage determination and in disaster observation, sensing, and simulation. The challenges in terms of mitigating damage from future catastrophic natural disasters, such as the expected Metropolitan Tokyo Earthquake and Nankai Trough Earthquake and Tsunami, are how we share the visions of the possible impacts and prepare to mitigate loss and damage, how we enhance society’s disaster resilience and the ability of society and social systems to prepare well, how we respond promptly and effectively to natural disasters, and how we apply lessons learned to future disaster management.

In recent years, a huge amount of information known as “disaster big data,” including data related to the dynamic movement of a large number of people, vehicles, and goods as IoT, has been obtained to understand how our society responds to natural disasters, both inside and outside the affected areas. The key question is how to utilize disaster big data to enhance disaster resilience.

Researchers with various areas of expertise are working together in a collaborative project called JST CREST: “Establishing the Most Advanced Disaster Reduction Management System by Fusion of Real-Time Disaster Simulation and Big Data Assimilation.” The project aims to identify possible disaster scenarios caused by earthquakes and tsunamis that occur and progress in a chained or compound manner, as well as to create new technologies to lead responses and disaster mitigation measures that help societies recover from disasters.

Since 2016, we have published three special issues entitled “Disaster and Big Data,” and now we will publish a fourth one which includes 10 research papers and 1 report. These aim to share the recent progress of the project as a sequel to Part 3, published in March 2018. As a guest editor of this issue, I would like to express our deep gratitude for the insightful comments and suggestions made by the reviewers and members of the editorial committee. It is my hope that the fruits of everyone’s efforts and outcomes will be utilized in disaster management efforts to mitigate damage and losses from future catastrophic disasters.

Enhancing social resilience in the event of natural disasters is a critical issue for Japan. It will requires a need huge efforts to further increase the physical preparedness; on the other hand, compared to increasing physical preparedness, enhancing social resilience is a cost-effective means of mitigating the effects of natural disasters. The Cross-ministerial Strategic Innovation Promotion program (SIP), the biggest national research program in Japan, selected a theme related to enhancing social resilience in the face of natural disasters in 2014. The authors of this special issue worked as a part of the SIP for five years and developed state-of-the-art technologies for the enhancement, namely, next-generation tsunami and heavy rain observation, integrated liquefaction counter-measures, methods for sharing disaster information, a real-time disaster estimation system, an emergency communication system, and the development of applications for regional use. Most of the technologies have been implemented in efforts at natural disaster mitigation following earthquakes and heavy rains in 2017 and 2018. The development and implementation of advanced technologies are the essence of the SIP because it aims to foster innovation. While the SIP is a Japanese government program, it promotes international utilization of the technologies it develops. There are many instances which might be studied better by developing and utilizing advanced technologies in various countries following different types of natural disasters. I hope that this special issue will be a gateway for readers who are interested in using such advanced technologies to mitigate natural disasters and enhance social resilience during such events.

Our research project titled “Integrated study on mitigation of multimodal disasters caused by ejection of volcanic products” began in 2014 under SATREPS (Science and Technology Research Partnership for Sustainable Development) and is now coming to an end in 2019. Indonesia has 127 active volcanoes distributed along its archipelago making it a high risk location for volcano-related disasters. The target volcanoes in our study are Guntur, Galunggung, Merapi, Kelud, and Semeru in Java, and Sinabung in North Sumatra. Guntur and Galunggung are currently dormant and are potentially high-risk volcanoes. Merapi generated pyroclastic flows along the Gendol River in 2010, which resulted in over 300 casualties and induced frequent lahars. New eruptive activity of Merapi began in 2018. The 2014 eruption of Kelud formed a gigantic ash plume over 17 km high, dispersing ash widely over the island of Java. Semeru continued minor eruptive activity, accompanying a risk of a dome collapse. The aim of our research includes disaster mitigation of the Sinabung volcano, whose eruption began to form a lava dome at its summit at the end of 2013, followed by frequent pyroclastic flows for approximately 4 years, and the deposits became the source of rain-triggered lahars. Our goal is to implement SSDM (Support System for Decision-Making), which would allow us to forecast volcano-related hazards based on scales and types of eruptions inferred from monitoring data. This special issue collects fundamental scientific knowledge and technology for the SSDM as output from our project. The SSDM is an integrated system of monitoring, constructed scenarios, forecasting scale of eruption, simulation of sediment movement and volcanic ash dispersion in the atmosphere. X-band radars newly installed by our project in Indonesia were well utilized for estimation of spatial distribution not only of rain fall in catchments but also of volcanic ash clouds. Finally, we hope the SSDM will continue to be utilized under a consortium in Merapi, which was newly established in collaboration with our projects, and extended to other volcanoes.