WATER LEVEL FLUCTUATION CAUSED BY TYPHOON IN LAKE NAKAUMI AND ITS EFFECTS ON WATER ENVIRONMENT

The water level in the Lake Nakaumi is predominated by that of the Japan Sea, and is affected not only by tide but also by meteorological factors. In this paper, wehave studied effects on water environment of the Lake Nakaumi by typhoons: Firstly, we have classified the typhoons according to the tracks following toward Japan and have shown thewater level fluctuations in the Lake Nakaumi while typhoons pass Japan. Secondaly, we have evaluated the water exchange while typhoon9719 has passed near the Lake Nakaumi. This study shows four types of typhoons depending on their tracks The water levels in the Lake Nakaumi aie effected by the type of typhoon. It is also observed that the volume of water exchange by the typhoon9719 in Lake Nakaumi is nine times as large as that of during ordinary condition.