都市化に伴う熱環境の変化に関する研究

リモートセンシングデータによる北部九州諸都市の解析

抄録

It is well known that the heat island intensity of cities, e.g., temperature difference between city centers and surrounding rural areas, becomes larger with the increasing size of urbanized areas. At the same time, physical structure of urban land surface is subject to rapid changes due to construction of higher buildings, increasing concrete covers, decreasing wooded areas, etc. All these factors related to urbanization accelarate the formation of heat islands and dry weather in cities. By using remote sensing data of LANDSAT, this study aims to quantify the relationships between the indices describing the above mentioned characteristics of urban heat islands (i.e., their intensity and dominant geographical areas) and various data representing the urbanization. For analysis, cities located in north Kyushu are taken up. Mesh data of their land use patterns and surface temperature distribution are obtained by LANDSAT TM data, then two studies are carried out. Firstly, the role of green tracts in the determination of heat island intensity is examined by changing the mesh sizes. Secondly, the relationship between the heat island intensity and the size of cities is analyzed. By regression analysis, empirical formulas describing the relationship between heat island intensity and urban indices such as vegetation ratio and city size are presented.