This study aims to organize and classify the contents of hazard and disaster-related questions in the National Center Test and clarify the trends and characteristics of these questions over time. The analysis was conducted for all the Center Tests from 1990 to 2020. The analysis was conducted for Earth Science and Geography containing many descriptions of disaster prevention. The results of the analysis showed that about 10% of the total number of points in Earth Science were related to hazards and disasters since 1990. Geography’s average percentage of hazard and disaster-related questions increased from 2.8% in 1990-1996 to 8.5% in 2015-2020. Earth Science has many questions about a single hazard or disaster. In Geography, there were many compound questions, such as questions about disasters that occur in a certain region.

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The 1611 Keicho Oshu tsunami is known to have caused extensive damage along the Pacific coast of the Tohoku region, but no consensus has been reached on the source. This is an important issue from the viewpoint of tsunami risk evaluation and disaster mitigation because without wave source information, it is impossible to understand the behavior of tsunami in each area. Therefore, tsunami source estimation using more information adding tsunami deposits as well as ancient documents as tsunami traces should be proposed and conducted. The estimated models with different mechanism are suggested to have a slip of 21 to 26 meters off the coast of Miyagi Prefecture like the 3.11 Tohoku earthquake. It is possible that the 1611 earthquake was a coupled earthquake that occurred in the same area as the 3.11 earthquake.

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University records from the Great East Japan Earthquake in 2011 and the Kumamoto Earthquake in 2016 described common problems, suggesting that the experiences of universities affected by past disasters have not been applied to disaster prevention measures at other universities. Therefore, based on the Great East Japan Earthquake and the Kumamoto Earthquake, we conducted a questionnaire survey to clarify the current status of disaster prevention systems at universities in Japan and the impact of disaster experiences. As a result, it was clarified that many universities have not taken measures such as safety confirmation, which has been an issue in the past disasters, and that the disaster experiences of other universities do not necessarily affect their disaster preparedness.

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In this study, we created a hazard map of landslides in Aruga, Suwa City, Nagano Prefecture, based on scientific and engineering perspectives. We examined the effects and issues of this approach from a questionnaire survey data. Landslide hazard slopes were identified by topographical analysis, and landslide range was then estimated from soil layer structure survey data in a representative stream. Subsequently, a debris flow simulation was conducted based on the scale of the landslide. Based on the above information, a landslide hazard map was created that can indicate the risk of landslides. Our study found that this map can contribute to the landslide hazard awareness among the residents and can be useful during actual heavy rainfall.

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This article reports the results of a survey of municipalities in Aichi Prefecture regarding the amount of food and bottled drinking water stockpiled, their expiration dates, and storage methods. The article points out the effectiveness of a system in which unaffected municipalities preferentially provide supplies with shorter remaining shelf lives to affected municipalities in the event of a disaster, and presents technical issues related to the storage and removal of supplies and the management of stockpile information for the practical implementation of this system.

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In recent years, many areas have been hit by natural disasters such as heavy rains and earthquakes, and it has been pointed out that small and medium-sized municipalities have repeatedly experienced similar problems in their initial response and ongoing emergency response. The purpose of this study is to analyze the actual status of disaster response capability issues of small and medium sized municipalities, based on the integrated contingency theory, using the results of a questionnaire survey conducted on disaster prevention departments of municipalities nationwide. As a result, the differences in the issues to be considered in improving disaster response capacity among municipalities by population size were quantitatively clarified by chi-square test and factor analysis. Then, the differences in the disaster preparedness measures recognized by municipalities by population size were quantitatively verified by principal component analysis, factor analysis and multiple regression analysis. From the above analysis results, it is suggested that it is necessary to consider specific measures according to population size to strengthen the disaster response capacity of municipalities.

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Typhoon No.14 (Nanmadol) landed near Kagoshima City around 19:00 on September 18, 2022, and landed again near Yanagawa City the next day at around 3:00 after going northward through Kyushu District. Thereafter, it changed course eastward, going across Fukuoka Prefecture and Yamaguchi Prefecture and then going offshore to the Sea of Japan by 15:00. Very intense rain continued to fall intermittently around the southeastern area of Kyushu Mountain from late morning on the 18th until early morning on the 19th, and the total precipitation from the 15th to the 19th was 1,235 mm in Watarigawa Dam, of the Omaru River system in northern Miyazaki Prefecture. Landslides occurred in Misato Town, Shiiba Village, and other areas. Even at the Gokase River’s tributary, the Hinokage River, in the northern part of the prefecture, 1,097 mm total precipitation was recorded, exceeding high water levels and leading to flood danger water levels in many places in the Gokase River system. Flood disaster occurred due to inland water flooding in Nobeoka City’s Tomiyama-machi, Misu-machi, Hosomi-machi and Ogawa-machi, Kitakata Town’s Kawazuru, and Kitagawa Town’s Sodachi; due to river flooding in Kitakata Town’s Soki and Yakai, where the authors took field surveys. Over 200 houses were damaged by the inland waters in the Tomiyama district of Nobeoka City, and a maximum inundation height of over 3 meters was measured in the riverside area of Kitakata Town.

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The Earthquake Research Council issued a long-term evaluation of earthquakes along the Nankai Trough in May, 2013. One of main points of this evaluation is that there is a 60–70% chance of the occurrence of earthquakes during the next 30 years. Several critical comments were presented before and after its announcement, especially on the adoption of the Time- Predictable model to obtain the interval between the last and impending earthquakes using water depths in the Kubono Family documents. We examined old documents including the Kubono Family documents and found several drawbacks. We confirmed that there is a lack of information that are essential for the evaluation of accuracy of measured depths, and construction works had been made almost every year since the opening of the port. Taking the information in available documents and results of recent tidal observations into account, the uplift during the 1707 Hoei earthquake may range between 1.4 m and 2.4 m. Therefore, the society should recognize this large uncertainty and reexamine the way to make use of this information.

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