Urban surface temperature and microclimate measurements in Thessaloniki

The urbanization and the deficiencies in proper development control have as consequence the environment's degradation in urban centres and the change of microclimatic conditions. So, the urban microclimate of densely built areas is characterized by higher temperatures than the temperature of the suburbs and surrounding areas. Heating of the atmosphere and surfaces in urban areas compared to their surroundings is the phenomenon which is called urban heat island (UHI).The effect of building's volume is considered as one of the main reasons for the urban heat island effect. Buildings, roads and paved surfaces, store the heat during the day and then release it slowly during the evening keeping the air temperature of the city hotter than surrounding areas. In other words, urban heat island cause thermal discomfort and it is responsible for the increase of energy demand in the buildings.This paper presents a study that aims at investigating the influence of urban morphology in microclimatic conditions. The investigation is carried out in Thessaloniki, Greece. The purpose of the research project is to measure how the temperature of building's surfaces vary and interact during the day and according to the microclimatic parameters. There is a daily measurement of the examinated factors. Street orientation and configuration of the building blocks (height of buildings, width of road) are also important factors for the analysis of the measurements.

► The research investigates the urban microclimate in Thessaloniki, Greece.
► Relation of building surface temperatures and microclimatic parameters.
► Relations with urban geometry, orientation, and materials thermal properties.
► Maximum surface temperatures observed in the street canyon and at the first floors.