抄録
Meteorological field observations were conducted at a small urban area in the lakeshore basin environment in summer. During the daytime of a clear, calm day, about 2000m height of the mixing layer were developed by the thermally induced circulation over the basin. The maximum of air temperature around the lake shore were recorded after 1500LST, and at 1800LST for the urban area. It is conjectured that the mechanism of a continuation of high temperature in urban area is mainly due to the complex factors such as the downward wind which brings high temperature of air mass by the circulations, the relatively high temperature of paved ground and roof surfaces, and the improved mass and heat exchange within and above the urban canopy layer. Numerical simulation was conducted to evaluate these convection and urban effects by a three-dimensional turbulent closure model. The results were in good agreement with observed value of air temperature, mixing ratio, and wind profiles. The large curculation also reproduced well, and it brought warm and dry air mass to the ground over the lake.
