Satellite and ground-based sensors for the Urban Heat Island analysis in the city of Madrid

The trend of the Urband Heat Island (UHI) of Madrid is analyzed by both ground-based weather stations and a satallite-based infrared sensor. First, we have developed a suitable algorithm employing satellite brightness temperatures for the estimation of the air temperature belonging to the layer of air closest to the surface. UHI spatial characteristics have have assessed using both air temperatures measured by the weather stations and brightness temperature maps from the SEVIRI (Spinning Enhanced VIsible and INfrared Imager) instrument on board MSG (Meteosat Second Generation) geostationary-orbiting satellite and MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard Terra and Aqua polar-orbiting satellites. Daytime and nighttime scenes taken between 2009 and 2010 have been processed. Analysis of the Canopy Layer Heat Island (CLHI) during summer moths reveals a mean growth in magnitude during nighttime around 5K, well described by both MODIS and SEVIRI sensors and confirmed by Urban Atlas Services, which provides very high resolution hot spot mapping of urban functional areas.