TITLE:
Mutiparametric Characterization of Atmospheric Particulate in a Heavy-Polluted Area of South Italy
AUTHORS:
Carmen De Marco, Antonella Boselli, Andrea D’Anna, Alessia Sannino, Gaetano Sasso, Mariano Sirignano, Nicola Spinelli, Xuan Wang
KEYWORDS:
PM, Particle Size Distribution, Optical Particles Properties, Remote Sensing
JOURNAL NAME:
Atmospheric and Climate Sciences,
Vol.12 No.2,
April
29,
2022
ABSTRACT: To obtain
a real-time image of atmospheric particulate matter (PM) in highly polluted
areas and to understand how the anthropogenic component linked to urban
activities (industrial activities, domestic heating, road traffic, waste
disposal) can locally affect near-surface measurement of PM, several
measurement campaigns were achieved in the Campania region (Southern Italy)
using both Lidar and in-situ instruments. A comparison between the obtained results highlights a good
correlation between the data and the potential of remote sensing instruments
for air quality monitoring. Data analysis was performed in terms of particle
backscattering coefficient profile at 355 nm, PM mass concentration, and size
distribution. Wind profiles, which covered a range of altitudes from 40 m to 290 m, were also used to study
sources and physical processes involved. Measurement carried out in a rural area with a
landfill site highlighted the presence of a homogeneous particulate layer throughout the sounded area due to winds driving
aerosol from the landfill to the surrounding areas. The size
distribution in mass concentration, highlighted a modal diameter moving towards
0.9 and 2 μm with a larger mass concentration of particles in the morning,
before noon and in the afternoon when a large number of trucks delivered solid
wastes. Moreover, large concentrations of particulate matter were measured in a
small urban town with few industrial activities which peak (211 ± 33 μg·m-3) was measured in the direction of the most
urbanized area, probably due to the lighting of the domestic heating systems.
Bimodal size distribution in number concentration was measured, indicative of
two types of
atmospheric particles sources: gas and liquid combustion (particles with sizes
below 80 nm), including vehicular traffic and domestic gas-heating, and biomass
combustion (particles with sizes of the order of 200 - 500 nm). Finally, data collected in a highly
populated and industrialized area highlights the presence of particles having a
high level of spherical geometry (aerosol depolarization below 5%) pointing
towards the industrial area. Conversely, the measurements performed pointing
toward other directions highlighted a diffused source of aspherical particles
(depolarization values of about 3%) spreading throughout all city territory.
The work showed as the co-location of remote sensing and near surface
instruments is a promising approach to studying aerosol properties in the
atmospheric layers and has more
accurate information on atmospheric dynamics. Moreover, the correlation between
the obtained results highlighted the potential of remote sensing instruments
for air quality monitoring.