Outdoor thermal sensation in a Mediterranean climate (Athens): The effect of selected microclimatic parameters

Abstract

The present study deals with the estimation of human thermal sensation zones in a Mediterranean climate (Athens). Field monitoring along with field surveys leading to a database of 2313 questionnaires were carried out in three open urban areas. Thermal sensation conditions were analysed under the influence of air temperature, relative humidity, solar radiation and wind speed. Thermal sensation zones were first defined using air temperature as a single parameter affecting thermal sensation. Logistic regression was appropriately used to define each thermal sensation zone. The thermal sensation zones were then determined using a combination of the microclimatic parameters to investigate the extent to which these parameters affect thermal sensation. Results showed that the thermal comfort zone is characterized by a quite wide air temperature range, on the order of more than 10°C. In addition, this zone presents always statistical insignificance in the P-values of residuals. These results imply that thermal comfort is a complex situation and adaptation plays an important role as far as this zone is concerned. By contrast, the other thermal sensation zones were found to present statistical significance in the P-values of residuals, implying thus that the examined microclimatic parameters seem quite adequate to define these zones.