Mapping Local Climate Zones with a vector-based GIS method
E. Lelovics, T. Gál, J. Unger
ABSTRACT. – Mapping Local Climate Zones with a vector-based GIS method. In this study we determined Local Climate Zones in a South-Hungarian city, using vector-based and raster-based databases. We calculated seven of the originally proposed ten physical (geometric, surface cover and radiative) properties for areas which are based on the mobile temperature measurement campaigns earlier carried out in this city.
As input data we applied 3D building database (earlier created with photogrammetric methods), 2D road database, topographic map, aerial photographs, remotely sensed reflectance information from RapidEye satellite image and our local knowledge about the area. The values of the properties were calculated by GIS methods developed for this purpose.
We derived for the examined areas and applied for classification sky view factor, mean building height, terrain roughness class, building surface fraction, pervious surface fraction, impervious surface fraction and albedo.
Six built and one land cover LCZ classes could be detected with this method on our study area. From each class one circle area was selected, which is representative for that class. Their thermal reactions were examined with the application of mobile temperature measurement dataset. The comparison was made in cases, when the weather was clear and calm and the surface was dry. We found that compact built-in types have more temperature surplus than open ones, and midrise types also have more than lowrise ones. According to our primary results, these categories provide a useful opportunity for intra- and inter-urban comparisons.
Keywords: urban heat island, Local Climate Zones, GIS method, Szeged, Hungary.