Source area estimation of urban air temperatures

In the urban areas, the estimation of air temperature from satellite derived land surface temperature is especially difficult due to complex topological settings with a large number of active surfaces and the unknown heat flux source areas. Since the source area approximates the surface area that interacts with the atmosphere at a given position and sensor height, knowledge of source areas is essential for air temperature estimation from satellite data. In this contribution we analyse a week of remote sensing observations made by an infrared camera and in situ air temperature measurements. The first results show that the source area is significantly smaller than operational weather satellites resolution.