During the DESIREX 2008 campaign, two flight lines along the NW-SE & the N-S urban axis have been done at 3 different times of the day (around sunrise, noon and midnight) in order to characterise the warming/cooling process of the urban areas. Some of the DESIREX 2008 flights have been organised contemporarily with an ASTER pass over the city of Madrid. This image shows the two flight lines and the footprint of an AHS-observed surface temperature area overlaid on an ASTER satellite image of the city of Madrid.