1 A NEW APPROACH TOWARDS MAPPING URBAN SEALING USING THE VERY HIGH-RESOLUTION SATELLITE DATA IN SEOUL METROPOLITAN AREAS

Sealed surfaces affect many environmental processes, including climatological and hydrological conditions, which have a direct impact on the quality of habitat and human life in a city. The sealing degree and the biotope area factor have been used as quantitative and qualitative indicators to measure the ecological values of urban surfaces. For this purpose, the advanced satellite remote-sensing offers a new potential with its geometrically, radiometrically and temporally improved high resolution. In this study, its possibilities and limits were tested in the urban area of Seoul. To deal with the particular situation of Seoul, a very densely and highly built-up metropolitan area, a new approach is needed for the satellite-data analysis and assessment because of large shadows and the oblique recording angle on buildings. This study therefore suggests a new concept for the comprehensive mapping of urban sealing. The very high resolution satellite data show large potentials for the detection of the sealing degree and the biotope area factor. The major benefits are the more or less automatically derived digital and objective information quickly to be up-dated and covering wide-range areas. However, the wholly automated remote-sensing based approach cannot fulfil the aims and requirements for the mapping of urban sealing as precisely and detailed as is desirable for urban-planning tasks. The visual interpretation of remotely sensed data or field surveying is still relevant. The best results can be achieved by combining the different methods. In future, these combined methods will be increasingly supported by high-resolution satellite data