When major natural disasters occur, not only scientific and national administrative parties but also individuals and organizations from the local areas affected by the disaster prepare a variety of reports. Considering the general structure of natural disaster processes that occur and progress in diverse and specific spatiotemporal conditions, such reports prepared locally are expected to contribute to both reminding residents of the disaster and to improving future hazard-mitigation measures of the area concerned. At the same time, being based on primary sources related to various hazard-triggered local events, the reports support a more comprehensive understanding of the disasters as a whole. This paper reviews numerous reports on major tsunami disasters that occurred on the Sanriku Coast, Northeastern Japan, since the late 19th century. Most reports on the 1896, 1933 and 1960 tsunami disasters were prepared by local intellectuals supported in some cases by local governments. After the 2011 tsunami, most stricken municipalities published reports with financial assistance from the national government, and some of them received reporting and editing assistance from outside experts, including scholars and journalists. As local reports are prepared in a situation of potentially plentiful primary sources related to various aspects of the disaster in the area, the results of such reports depend heavily on the collection and presentation of primary sources. Report writers, including outside experts, contribute to reporting, editing, and presenting using suitable images, maps, tables, and narratives. For more effective use of the primary sources, it is suggested that these people have an adequate perspective of both the overall structure of disaster processes and the local conditions of the area concerned.
