Sensitivity of spatial indicators for urban terrain characterization

To develop and manage urban territories and to analyze urbanisation impact on environment, an accurate knowledge of the city and its urban fabric is necessary. A physical description like building morphology or land cover/use allows some characterization of the urban terrain. A specific package for a GIS software is developed for urban analysis: UrbSAT (Urban Spatial Analysis Tool). It allows extracting knowledge from various data sources and gives some indicators to real applications (sustainable development, management policy, air quality improvement, etc). It raises issues such as database accuracy and quality, cell shape, size and orientation for the construction of spatial indicators. We present some tests to address those issues.