Computing continuous sky view factors using 3D urban raster and vector databases: comparison and application to urban climate

The use of high resolution 3D urban raster and vector databases in urban climatology is presented. It applies two different methods to the calculation of continuous sky view factors (SVF), compares their values and considers their usefulness and limitations in urban climate studies. It shows and evaluates the relationship between urban geometry, quantified by SVF, and intra-urban nocturnal temperature variations using areal means in the whole urban area of Szeged, a city located in southeast Hungary. Results from the vector and raster models shows similar SVF values (r (2) = 0.9827). The usefulness of using areal means in SVF-temperature relations is confirmed. The vector and the raster approaches to the derivation of areal means of SVF are both shown to be powerful tools to obtain a general picture of the geometrical conditions of an urban environment.