Predictive
models based on mobile measurements have been increasingly
used to understand the spatiotemporal variations of intraurban air
quality. However, the effects of meteorological factors, which significantly
affect the dispersion of air pollution, on the urban-form–air-quality
relationship have not been understood on a granular level. We attempt
to fill this gap by developing predictive models of particulate matter
(PM) in the Bronx (New York City) using meteorological and urban form
parameters. The granular PM data was collected by mobile low-cost
sensors as the ground truth. To evaluate the effects of meteorological
factors, we compared the performance of models using the urban form
within fixed and wind-sensitive buffers, respectively. We find better
predictive power in the wind-sensitive group (R =
0.85) for NC10 (number concentration for particles with
diameters of 1 μm-10 μm) than the control group (R = 0.01), and modest improvements for PM2.5 (R = 0.84 for the wind sensitive group, R = 0.77 for the control group), indicating that incorporating meteorological
factors improved the predictive power of our models. We also found
that urban form factors account for 62.95% of feature importance for
NC10 and 14.90% for PM2.5 (9.99% and 4.91% for
3-D and 2-D urban form factors, respectively) in our Random Forest
models. It suggests the importance of incorporating urban form factors,
especially for the uncommonly used 3-D characteristics, in estimating
intraurban PM. Our method can be applied in other cities to better
capture the influence of urban context on PM levels.