The effect of vegetation in outdoor thermal comfort in archaeological area in urban context

Abstract

The characteristics of the outdoor microclimate influence directly the outdoor thermal comfort that depends on surface reflectance, green albedo, trees, buildings, sky view factors, etc. Several researches and studies about outdoor microclimate examine area of cities, districts, squares, streets, parks, etc. and a proportion of this research studies is about the effect of outdoor microclimate on people thermal comfort, e.g. measure following Physiological Equivalent Temperature (PET). Thermal comfort in outdoor spaces has the crucial role of guaranteeing a comfortable staying in public places (such as squares, parks, etc.), as without thermal comfort people won't stay in such places. For this reason, research on tourism focuses more on outdoor thermal comfort than on indoor thermal comfort (e.g. in museum). Designing archaeological sites is very interesting and complex, since it's possible to study different scenarios and themes, together with strategies focused on solving and enhancing specific situations. Those, indeed, can vary: archaeological areas can be seen both as an exhibition area – focusing more on its relics and their correct preservation – or as an outdoor space – focusing more on the outdoor comfort, not just for the area itself but for the visitors too. In this paper we therefore report a thermal comfort and microclimate case study considering how the transformation of the urban area that surrounds an archaeological site could improve the outdoor comfort for tourists. This study uses the ENVI-met software to reproduce the actual area and six scenarios based on different urban modifications of said area: thermal variables such as air temperature, relative humidity, surface temperature and PET are considered to understand if said changes can have a positive or negative impact on thermal comfort for tourists. Comparing real and simulated data we get to focus on the scenarios with the most positive impact, in order to understand how the city could change to improve the presence of tourists in the area and what are the key elements to reach the outdoor comfort.