洞爺湖における風系

概要

論文の詳細を見る
The effect of a caldera lake surrounded by the mountains and hills on the wind flow pattern over the lake was investigated in this study. Two objects were studied in this paper. One was to clarify the influence of lakes on the meteorological phenomena over the surrounding area, and the other was to obtain fundamental data for the assessment of environmental changes caused by man-made lakes. The series of observations were carried out on and around Lake Toya, about 60 km southwest far from Sapporo, in the spring, summer and autumn of 1978. The surface wind, upper wind and water temperature were observed for about two weeks in each season. From these observations the following features were noted. 1) The land and lake breeze system over Lake Toya and its surrounding region were observed in a series of observations. Land breezes were observed during the night and early in the morning. And after sunrise the lake breeze blew and continued until about noon during these seasons. The wind speed of land and lake breeze were approximately 1-2 m/sec. It appeared that the extent of the land and lake breeze were limited within the caldera judging from the trajectories of the pilot balloon. 2) In the afternoon the lake breeze ceased to blow and lake was exposed to a comparatively strong wind. The wind flow patterns over the lake and its surrounding region were classified into three types, affected by topographical conditions. 3) Even when the upper winds were weak, a south-westerly wind prevailed over the lake. It is considered to be the sea breeze from Uchiura Bay. By the sea breeze, the lake breeze system (divergent wind) was disrupted late in the morning. Then, the wind became strong at the leeward shore of the Lake. It seems to be the result of a building up of the lake breeze and sea breeze. 4) In summer, as the land and lake breeze developed, the air temperature became 2-3℃ lower than that of the water temperature at the outset of the lake breeze. And these phenomena continued for about two hours. It was suggested that cold air had flown into the lake from inland at night, and a sufficient exchange of heat of the lake surface had not set in.
北海道大学の論文
1980-03-28

洞爺湖における風系

スポンサーリンク

概要

著者

関連論文

スポンサーリンク