A Field Study on the Spatio-temporal Distribution of PM2.5 in Shanghai's Urban Street Canyons: An Analysis of Geometrical and Meteorological Influences

Guandi Zeng

doi:10.54097/71kywf54

Authors

Guandi Zeng

DOI:

https://doi.org/10.54097/71kywf54

Keywords:

PM2.5; Urban Street Canyon; Spatial and Temporal Distribution; Air Pollution.

Abstract

This study reveals that the daily mass concentration of PM2.5 in the street canyons of Shanghai's Yuanshen Road exhibits a characteristic "V"-shaped pattern. Field measurements from August 22nd to 24th, 2025, also identified a clear spatial hierarchy, with pollution levels descending from road intersections to roadsides, community parks, and finally to general street canyons. Several factors were found to mitigate PM2.5 concentrations, including increased wind velocity, greater distance from emission sources, and the presence of green plants. A regression model further highlighted humidity as a more significant determinant than temperature for PM2.5 levels during the summer measurement campaign. These findings are critical for understanding and improving air quality in urban street canyons, which constitute the primary habitats for city residents and are heavily impacted by PM2.5 pollution.

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References

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