How the morphology of urban street canyons affects suspended particulate matter concentration at the pedestrian level: An in-situ investigation

Miao, Chunping; Yu, Shuai; Hu, Yuanman; Bu, Rencang; Li, Qi; He, Xingyuan; Chen, Wei

doi:10.1016/j.scs.2020.102042

Cited by 60 publications

(52 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The estimation of SVF was determined by fisheye photography methods [18]. This is a method to estimate SVF using fisheye photos taken vertically of the sky with a circular fisheye lens.…”

Section: Estimation Of Ar and Svfmentioning

confidence: 99%

“…This is a method to estimate SVF using fisheye photos taken vertically of the sky with a circular fisheye lens. This method was widely used for SVF estimation because its accuracy was high enough to test the accuracy of other technologies [18]. In this study, circumpolar fisheye photos were taken vertically of the sky at 1.5 m above the ground in street canyons using a digital camera (Nikon, D800, Tokyo, Japan) equipped with a fisheye lens (AF-S Fisheye NIKKOR 8-15 mm f/3.5-4.5 E ED, Tokyo, Japan).…”

Section: Estimation Of Ar and Svfmentioning

confidence: 99%

“…The O 3 concentration was low in narrow street canyons divided by SVF, whereas it was high in deep canyons divided by AR (Figure 2). The SVF represents the proportion of visible sky compared to the areas obscured by buildings or trees [18]. Decreasing the building height along the two sides of street canyons results in an increase in SVF unless there are street trees [18].…”

Section: Distribution Of O 3 Concentration In Street Canyonsmentioning

confidence: 99%

“…Pollutant distribution and dispersion in street canyons were closely associated with street canyon morphology [13][14][15]. Street canyon morphology can be characterized as building height (BH), aspect ratio (AR, building height/street width), and sky view factor (SVF) [16][17][18]. Decreasing the street aspect ratio or increasing the length might improve the rate of pollutant removal through turbulent diffusions across canopy roofs in canyons with uniform heights [19][20][21][22].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Assessing Ozone Distribution Vertically and Horizontally in Urban Street Canyons Based on Field Investigation and ENVI-met Modelling

Miao

Chen

2022

Buildings

Self Cite

View full text Add to dashboard Cite

High concentrations of ozone (O3) is a major air problem in urban areas, which creates a serious threat to human health. Urban street canyon morphology plays a key role in air pollutant dispersion and photochemical reaction rate. In this study, a one-year observation at three height levels was performed to investigate the O3 distribution vertically in a street canyon of Shenyang. Then, field investigation and ENVI-met modelling were conducted to quantify the influence of street canyon morphology and microclimatic factors on O3 distribution at the pedestrian level. All O3 concentrations at the three height levels were high from 1:00 p.m. to 4:00 p.m. Both O3 concentrations at pedestrian level and the middle level in the canyon were 40% higher than at roof level. O3 accumulated in the canyons rather than spread out. The in-canyon O3 concentrations had significantly positive correlations with building height, aspect ratio, sky view factor, air temperature, and wind speed. Both field investigation and ENVI-met modelling found high O3 concentrations in medium canyons. Photochemical reaction intensity played a more important role in in-canyon O3 distribution than dispersion. Wide canyons were favorable for removing O3.

show abstract

“…The estimation of SVF was determined by fisheye photography methods [18]. This is a method to estimate SVF using fisheye photos taken vertically of the sky with a circular fisheye lens.…”

Section: Estimation Of Ar and Svfmentioning

confidence: 99%

Section: Estimation Of Ar and Svfmentioning

confidence: 99%

Section: Distribution Of O 3 Concentration In Street Canyonsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Assessing Ozone Distribution Vertically and Horizontally in Urban Street Canyons Based on Field Investigation and ENVI-met Modelling

Miao

Chen

2022

Buildings

Self Cite

View full text Add to dashboard Cite

show abstract

“…In recent years, the link between urban morphology and air pollution has been investigated by focusing on key but single properties as the urban shape 15 , the packing density of buildings 16 , 17 and the geometric characteristics of the street canyons 18 . However, a comprehensive analysis of how propagation of pollutants in the streets depends on the characteristics of the urban fabric is missing so far.…”

Section: Introductionmentioning

confidence: 99%

Vulnerability of cities to toxic airborne releases is written in their topology

Salizzoni

Ridolfi

2021

Sci Rep

View full text Add to dashboard Cite

The incidental or malicious release of toxic gases in the atmosphere is one of the most critical scenarios for cities. The impact of these releases varies with the ventilation potential of the urban environment. To disentangle this crucial aspect, vulnerability to airborne releases is here traced back to essential properties of the urban fabric. To this aim, pollutant dispersion is disassembled in its fundamental bricks and the main drivers of the process are captured. The analysis is based on four cities with emblematic architectures: Paris, Firenze, Lyon and New York. Results show that vulnerability is driven by the topology of the city and by its interaction with the approaching wind. In this sense, fragility to toxic releases is written in the layout of the urban fabric and results from its historical evolution. This study paves the way to the assessment of air pollution-related issues from a morphological point of view.

show abstract