Statistics on avalanche disasters in the Joetsu region, including the cities of Joetsu, Myoko and Itoigawa in Niigata Prefecture, over the past 134 years from 1883 to 2016 and data on the annual maximum snow depth for 127 years at Takada in Joetsu City were investigated to clarify the succession and characteristics of avalanche disasters. In total, 556 avalanche disasters and 340 dead or missing persons were recorded during the 134 years. The avalanche disasters occurred mostly in February, and 512 (92%) disasters occurred in January‒March. During the 43 years from 1922 to 1940 and from 1963 to 1985, 420 (76%) avalanches occurred; 226 avalanches mainly affecting railways occurred between 1922 to 1940, and 194 avalanches mainly affecting roads occurred between 1963 to 1985. During the 19 years from 1922 to 1940, 202 (59%) persons died or went missing. The greatest number of avalanche disasters in one winter was 50, recorded for 1926/1927, with 57 dead or missing persons (the second largest after 97 persons during the winter of 1921/1922) when the annual maximum snow depth was 375cm (the second largest depth after 377cm during the winter of 1944/1945) in the Joetsu region. Heavy snow fell continuously over the entire Joetsu region in February 1927, and multiple, simultaneous avalanche disasters occurred in coastal areas of
this region, with 80% of dead or missing persons resulting from avalanches hitting houses.
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