Documenting 19th Century Typhoon Landfalls in Japan

Abstract

Japan is located in the Western North Pacific basin, the most active tropical cyclone region in the world. For the most recent normal period (1981-2010), an annual average of 25.6 typhoons formed in the basin with 5.4 of those storms coming within 300 km of the four main islands of Japan. Throughout the history of Japan, typhoons have been a major hazard bringing strong winds, high waves, and heavy rainfall with flooding and landslides to the country nearly every year. With or without potential changes in typhoon frequencies and intensities caused by anthropogenic climate change, typhoons are a significant problem for Japan. Most studies of typhoons in the Western North Pacific depend on modern data dating back only to 1951 with the more accurate satellite observations beginning in 1965. As a result, our understanding of typhoon behavior over the long term and under differing global climatic conditions remains incomplete. However, records and data do exist for earlier periods and can be used to reconstruct typhoon histories. Such records can used for periods that have no instrumental data and to add detail to periods with limited data. In our research, we use data from historical documents to reconstruct a list of typhoons affecting Japan in the 19th century and to describe and map these typhoons. We use data from: 1) Japanese historical documents including official and private diaries that have been entered into a Historical Weather Database; 2) Japanese government and academic compilations; 3) weather observations and compilations from outside Japan; 4) English language newspapers published in Japan; 5) Japan Imperial Meteorological Observatory Maps and Records. Combining data from these multiple sources makes it possible to reconstruct a meaningful record of typhoons of the past. This paper will review the data and methods we used, discuss some results to date, and preview potential uses for this research.