Trees and the Microclimate of the Urban Canyon: A Case Study

Abstract

Urbanization generally influences the microclimate by changes introduced in land cover, the compact spatial structure of the metropolitan areas, the emission of pollutants, the modification of the physical properties of the surfaces, etc. The frequently observed steady increase of urban air temperatures around the world is considered to be a cumulative effect of all of the above mentioned parameters. Higher air temperatures, especially during the summer season, may have major implications for local air quality, heat stress, morbidity, mortality and energy demand. In this context, the present study investigates the capabilities of vegetation to attenuate microclimatic extremes. Specifically, we explored the diversity of microclimatic conditions in two parallel streets (in Vienna, Austria), one with trees, and the other one without. Simultaneously monitored data from two mobile weather stations was obtained for the selected study areas during hot and sunny days in August 2012. Using the collected data, the temporal cooling effects of vegetated areas was systematically studied.