Recent studies on the influence of climate change on Northern –European cities suggest that within 50 years they may experience a climate close to that of South-European cities today. This has enormous resource implications when the design and layout of the urban fabric and the individual buildings are not well suited to mitigate extreme conditions. There is therefore a strong need for strategic designs to be developed which would mitigate such environmental changes. For example, whilst the general cause of overheating of cities is known, it is not well understood how much influence different urbanization characteristics and building materials have on the intensity of the city overheating and thereby on the energy demand maintaining thermal comfort conditions. This research is conducted under the TOPEUM European Research Project funded by ERA-NET and aims to investigate the influence of different urbanization characteristics, such as the density of buildings within the city, canyons aspect ratio and orientation, and the building surface materials on the intensity of the urban heating effect, in the case of a real city. We have used an inter-disciplinary approach involving in a complementary way both computational and experimental methods: Computational Fluid Dynamics (CFD) simulations, wind tunnel laboratory experiments and field measurements. The field measurement campaign was carried out in the city of Nicosia (Cyprus), a typical Mediterranean city both in relation to buildings architecture and fabrics, street geometry and neighbourhood morphology. A series of measurements were taken simultaneously both for the air, solar radiation, humidity as well as the building surfaces. The field measurements involved meteorological measurements at three different scales (from mesoscale to microscale), while the thermal response of buildings was simultaneously recorded through thermography (both aerial and on-ground) as well as in-situ measurements of temperature and moisture.

In this paper we will present the results from this field measurement campaign, our analysis and interpretation, as well as results from supporting studies in the wind tunnel and computational simulations to assist in the understanding and derivation of routes to guidelines for improved urban design.