Abstract:

Urbanization has a significant impact on the surface environment and land surface temperature (LST) can be used as reliable indicator of the Surface Urban Heat Island effect that is caused by it. Here, the relationship between LST and the Athens urban landscape is investigated, using very high resolution airborne nighttime LST image data, obtained during the ESA’s 2009 THERMOPOLIS campaign for three typical summer days (warm day, day with strong Etesian winds and heat wave day). The landscape is represented by the percentage of built-up area coverage per spatial unit provided the European Settlement Map (ESM), spatially averaged on the European Urban Atlas land use map, both provided by Copernicus Land Monitoring Service. It is found that the LSTs exhibit statistically significant differences among the different urban land cover/land use (LCLU) classes, but also among the different days for the same LCLU. A modelled global relationship between LST and landscape can be constructed, though hot and cold spots exist, which indicate clustered areas with higher and lower LSTs. The hotspots coincide with the city centre area of dense fabric and the deviations are maximized with unfavourable meteorological conditions, i.e. heat waves and windless days.

Poster