災害教育の重要性は認められているが，火山災害教育における研究は課題が多い．そこで，平成に入ってからの学校教育における火山災害教育はどのように実践されてきたのかについて振り返り，その教育効果や課題を再確認した．その結果，様々な取り組みや工夫がみられたが，子供目線の教育や防災を前面に出さない教育等が行われていることが分かった．活火山のある地域の学校では現地に出掛けるなど，より具体的で実践的な授業が行われていることが分かった．火山モデル実験も様々な開発が行われてきており，キッチン火山実験やコーラマグマの噴火モデル等，子供達を引き付ける工夫がなされている．また，立体模型を使った実験も見られ，３Ｄプリンタの普及による充実が期待される．児童生徒の防災・減災や的確な避難行動につながる火山防災教育は着実に充実してきている．

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A critical review was made on public communication/education of knowledge and information about volcanoes and their risk in Japan. Volcanic process can socially be divided into four periods: dormant, pre-emergency, emergency, and restoration/rehabilitation periods. For better mitigation of disasters during all these periods, knowledge and information about volcanoes should enough be shared among volcanologists, officials, and residents around volcanoes. Psychologists well studied the methodology of decision-making and public communication under various risks and many of the results can be applied to volcanic risk. Many volcanologists, however, do not well know the achievements by psychologists. Several Japanese volcanological terms, which have been traditionally used in the public information/education, are ambiguous and have potential for misunderstanding. Journalists often distort the information from volcanologists. The internet may provide a better place for direct risk-communication between volcanologists and residents around volcanoes. Volcanologists should systematically survey the residents and know what method of public communication is the best for sharing risk infomation. The author summarizes the present status of the Japanese system for risk evaluation and announcement during volcanic crises and reviews the problems, which were exposed during the recent volcanic crises in Japan. The author also reviews the status of risk education using hazard maps and/or other methods, which include outreach programs for citizens and schoolchildren.

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The Yakedake volcano is located in the southern part of the northern Japan Alps, central Japan. Yakedake volcanic hazard map was published in March 2002, and in June 2002, it was distributed to the inhabitants of Kamitakara village, Gifu prefecture, where is located 4-20km west from the volcano. In January 2003, the questionnaire survey was carried out on the inhabitants in order to know their attitudes to the volcanic hazard map and the level of their understanding of the contents of the hazard map. The Kamitakara village office distributed the questionnaires to 1,102 families through the headman of each ward, the headman collected 802 answers. The results of analysis were as follows. 89% of the respondents knew the existence of the hazard map and 35% read it well, but about 11% have not read the map at all. The elders have a tendency to have deeper understanding of the hazard map than younger ones, especially in elders who have experiences to meet some kinds of natural hazards. And the people who once attended the explanatory meeting of the hazard map, which was held for the residents living inside the disaster-prone area four times after the publication of the hazard map, also tend to have more proper understandings. The people who are engaged to the tourism give more attention to the volcanic hazard than others. The respondents have strong tendency to require more knowledge about the volcanic activities and hazards. We can say that the further activities by scientists, engineers and administrative officers are expected in order to establish an informed consent, that is, there should be a decision-making by inhabitants themselves and support by officers in charge with detailed explanations.

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In the 1970s, a volcanic hazards program was started in Hokkaido, Japan. The first hazard map was published for Hokkaido-Komagatake volcano in 1983. The effects of the eruption on Izu-Oshima volcano in 1986 led to the preparation of nine volcanic hazard maps. From the late 1990s, many hazard maps were published, after the 1990-1995 eruption of Unzen volcano and the 2000 eruption of Usu volcano. The turning point for the preparation of the hazard maps came about during the 2000s when the Japan Meteorological Agency established the volcanic-alert-level system. Subsequently, the Japan Meteorological Agency changed the policies of the system after it was evaluated in 2003, based on the intensity of eruptions, and in 2007, based on the distances of the eruptions from populated areas. Afterwards, social factors were also taken into account, resulting in more complex planning scenarios for volcanic hazards programs that involved linking multiple administrative authorities in Japan. For such situations, various scenarios for mitigating volcanic hazards have been introduced for many volcanoes.

Two significant eruptions occurred after the introduction of the volcanic-alert-level system:the 2011 eruption of Shinmoedake in Kirisima volcanoes, and the 2014 eruption of Ontake volcano. The sub-Plinian eruptions on Shinmoedake caused some confusion in the implementation of the evacuations, but no one was killed in this incident, which was assigned an alert level of 2. The phreatic eruption of Ontake volcano, which claimed 63 lives, was assigned an alert level of 1. This article was prepared according to the list of hazard programs for each of these two volcanoes before their respective eruptions.

The hazard maps showing the precise locations of vents or areas of volcanic hazards in the cases of Usu volcano and Shinmoedake volcano likely helped facilitate evacuation during their respective eruption. Therefore, volcanic hazard mapping requires the accurate location of vents and accurate estimates of volumes of volcanic materials that can be set in motion during volcanic crises. Additionally, local administrations need to prepare case-study hazard maps based on volcanic crisis scenarios that consider the intensities and possible occurrences of volcanic eruption phenomena similar to those that occurred during the Kirishima eruptions. It is desirable that such maps conform to the volcanic alert levels assigned by the Japan Meteorological Agency. In 2015, the Act on Special Measures Concerning Active Volcanoes was amended taking into account the tragic outcome of the Ontake eruption in 2014. This article provides recommendations for volcanic hazards mitigation programs that can be implemented at locations near volcanic vents for the safety of hikers and tourists. This article also discusses the tasks and prospects of the implementation of volcanic hazard programs in Japan.

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Shinmoedake (Kyushu, Japan), which is one of the Kirishima Volcanoes, experienced several small eruptions in 2010, finally culminating in a sub-plinian eruption on January 26-27, 2011. After this sub-plinian phase, the eruption style shifts to the phase of vulcanian eruption or ash emission. This volcanic activity is still occurring. We here summarize the eruption history of Shinmoedake during the Edo period on the basis of historical records. The eruptions of Shinmoedake during the Edo period occurred in AD 1716-1717 (Kyoho eruption) and AD 1822 (the 4th year of Bunsei eruption). The Kyoho eruption, which was a large-scale (total amount of tephra: 2×10¹¹ kg) eruption, is divided into the following seven stages. Stage 1 (Apr. 10, 1716 to May 7, 1716): small eruptions occurred over two months; Stage 2 (Sep. 26, 1716): falling ash first observed at the foot of Shinmoedake; Stage 3 (Nov. 9 to 10, 1716): the first large eruption was observed, with pumice falling over a wide area; Stage 4 (Dec. 4 to 6, 1716): small eruptions; Stage 5 (Feb. 9 to 20, 1717): the second pumice fall eruption, with an intermittent ash fall eruption thereafter; Stage 6 (Mar. 3, Mar. 8, Mar 13, Apr. 8, 1717): ash fall eruptions; Stage 7 (Sep. 9, 1717): the last ash fall eruption. These eruptions, which continued intermittently over 17 months, were characterized by multiple repetitions of a large eruption. Based on the results of a comparison between the Kyoho eruption and the 2011 eruption, the eruptions from March 30, 2010 to January 26, 2011, were similar to Stages 1 to 3 of the Kyoho eruption; the eruptions after January 26, 2011, were similar to Stages 5 to 6 of the Kyoho eruption. In addition, the relatively large eruption events of Stages 3 and 5 of the Kyoho eruption and the January 26-27, 2011, eruption began without any noticeable precursors. The eruption in the 4th year of Bunsei (AD 1822) was a small eruption that lasted less than a day. The recent eruption sequences, which were also similar to the Edo period eruptions, are divided into a small-scale eruption (the 1959 eruption) and a large-scale eruption (the 2011 eruption). The eruption duration time of the small-scale (total amount of tephra: ＜ 10¹⁰ kg) eruption was less than a day. The eruption duration time of the large-scale (total amount of tephra: ＞ 10¹⁰ kg) eruption could be a few months or years. Both eruption sequences began with a small eruption. A large-scale eruption can occur a few months after the start of the eruption sequence. This is an important turning point in the eruption sequence of Shinmoedake.

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