台風9119号による塩害と内陸への塩分侵入量について

Abstract

The typhoon 9119, landed at the north-western part of Kyushu on Sept. 27, 1991, passed through the coast of the Japan Sea and landed again at Hokkaido. The typhoon 9119 recorded the high wind speed and the small amount of rainfall in a large area.Electric supply facilities such as the power station, the transformer substation, the power line, the power supply line were damaged and electric power failure occurred in Yamaguchi, Hiroshima and Okayama Prefecture which face the Seto Inland Sea. More than 100 samples of impacted sea salt, observed by the Chugoku Electric Company, were analyzed.The total amount of salt transported from the sea to the land by the typhoon 9119 was estimated as about 0.4mg/cm^2 in the coastal area of Hiroshima Prefecture. The effect of Kyushu and Shikoku islands on the sea-salt concentration at the coast of these Prefectures were estimated. The concentraion would not reach the equilibrium value, unless the strong wind blew on the sea surface over more than 100 km distance, or more than one hour.