A PET-Based Evaluation of Urban Thermal Comfort and Pedestrian Activity in Hot Arid Cities

Abstract

Thermal comfort significantly affects human activity in outdoor urban spaces, especially in
hot arid cities. This study examines the relationship between microclimatic conditions and
pedestrian movement along two streets with different orientations, Northeast-Southwest and
East-West, in Biskra city, Algeria, during spring and summer. The methodological approach
combined unobtrusive pedestrian observations using the gate-count method with thermal
comfort assessment based on the Physiological Equivalent Temperature (PET) index using
RayMan Pro software. Results show that pedestrian presence is not determined solely by
micrometeorological conditions. In spring, a strong positive correlation was identified between
PET and pedestrian attendance on the East-West Street, while the Northeast-Southwest Street
showed no significant correlation. During summer, both streets exhibited negative
correlations, with a notable decline in pedestrian numbers during the extreme heat period.
These findings provide valuable insights for designing more thermally comfortable outdoor
environments, encouraging public space use, and improving urban vitality.