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Environmental Science
Climatology

An observational analysis of shade-related pedestrian activity

Profile image of Or AleksandrowiczOr Aleksandrowicz

2025, Buildings & Cities

https://doi.org/10.5334/BC.574
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Abstract

The impact of shade on pedestrian travel activity is examined through observation of a large sample of sidewalk users at a variety of urban sites under hot and sunny conditions. Extensive data collection in the city of Tel Aviv-Yafo, Israel, included micrometeorological measurements alongside pedestrian counts, using high-frequency imaging at 34 sites during summer daytime hours. A sample of individuals (n = 5263) identified approximately 60% as being in the shade. The actual availability of shaded space was found to be a consequential factor, as the relative quantity of shaded space correlated strongly and directly with the percentage of people using it. Thus, at sites in which the areas of shaded and unshaded space were relatively equal in quantity and functionality, the proportion of pedestrians travelling in the shade increased to over 70%. Additionally, the intensity of solar exposure-calculated as the total incidence of direct and indirect solar radiation on the body of a standing person at the time of observation-was shown to have a strong correlation with the percentage of pedestrians travelling in the shade. These findings substantiate the imperative for generous shade provision in thermally stressful pedestrian environments.

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LOUAFI BELLARA Samira

2017

The effect of climate on the use of outdoor spaces in urban environments is particularly important for activities that occur in these areas. The consideration of the thermal and visual outdoor conditions in cities is increasingly important for the well-being of man and the use of public spaces. Vegetation zones play a significant role in the city through their visual appeal and their regulation of microclimates. Considering the microclimatic modification produced by vegetation, the objective of this research is to compare the performance of areas shaded by five different types of tree coverage, including an open area without vegetation, located in a hot and dry climate. The methodology is based on a combination of in situ measurements and thermal and visual comfort surveys. Measurements of air temperature, air humidity, wind speed, solar global radiation, luminance and the sky view factor combined with comfort surveys were performed during summer in five different areas of a square ...

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