TMと国土数値情報を用いた海風による地表温度低下効果の解析

抄録

In this parer, a temperature decrease by thermal interaction between the atmosphere and the land surface was analyzed in relation to the existence of sea breezes, extracting the distribution of land surface temperature on a single kind of land-use with Landsat TM and land-use data from National Digital Land Information. The land-surface temperature values in the coastal areas on the leeward side of the Japan Sea were found to decrease due to sea breezes horizontally and cross-sectionally regarding land-use of paddy fields or forests in Shimane Prefecture. Two spots were chosen to express the decrease in land-surace temperature due to sea breezes using the temperature difference between two points, one located in the leeward coastal area and the other inland.
The temperature decrease effect on leeward areas of the water related not only to wind speed but also the sea surface temperature and the atmospheric one. The effect was found to increase with the product U(T_a-T_w), which means the sensible heat, of the wind speed U and the difference between atmospheric temperature T_a and the sea surface T_w. According to the existence of this phenomena, the surface temperature is not only a fixed thermal boundary condition on the soil-plant-air system but another which needs to be considered from interaction with the atmosphere.