Recent
changes
in
energy
and
environmental
policies
along
with
the
markets
of
New
York
State
over
past
two
decades,
have
spurred
interest
evaluating
their
impacts
on
emissions
from
various
sectors
such
as
power,
transportation,
residential.
This
study
focused
quantifying
these
effects
subsequent
air
quality
within
City
(NYC)
metropolitan
area.
The
NYC
area,
its
more
than
23
million
residents,
is
an
EPA
nonattainment
region
for
ozone
(O3)
likely
a
VOC
(volatile
organic
compounds)
limited
region.
has
complex
coastal
topography
meteorology
low-level
jets
sea/bay/land
breeze
circulation
associated
heat
waves,
leading
to
summertime
O3
exceedances
formation
secondary
aerosol
(SOA).
To
date,
no
comprehensive
source
apportionment
studies
been
done
understand
contributions
local
long-range
sources
VOCs
this
applied
improved
Positive
Matrix
Factorization
(PMF)
methodology
designed
incorporate
atmospheric
dispersion
photochemical
reaction
losses
provide
results.
Hourly
measurements
were
obtained
Photochemical
Assessment
Monitoring
Station
located
at
urban
site
Bronx,
2000
2021.
further
explores
role
SOA
leverages
advanced
machine
learning
tools,
XGBoost
SHAP
algorithms,
identify
synergistic
interactions
between
provided
ambient
concentrations.
Findings
could
assist
regulatory
agencies
developing
appropriate
policy
management
initiatives
control
pollution
metro
Atmospheric chemistry and physics,
Journal Year:
2025,
Volume and Issue:
25(1), P. 625 - 638
Published: Jan. 17, 2025
Abstract.
BTEX
(benzene,
toluene,
ethylbenzene,
and
m-xylene,p-xylene,
o-xylene)
are
significant
urban
air
pollutants.
This
study
examines
variability
across
7
European
countries
using
data
from
22
monitoring
sites
in
different
settings
(urban
background,
traffic,
industry,
suburban
background).
Results
indicate
that
the
relative
abundance
of
areas
follows
order
toluene
>
benzene
m,p-xylene
o-xylene
with
median
mixing
ratios
266
±
152,
163
74,
129
88,
53
35,
45
27
ppt
during
years
2017–2022,
respectively.
Seasonal
trends
show
had
similar
concentrations
industrial
sites,
indicating
mixed
sources.
Toluene
levels
were
highest
traffic
areas,
highlighting
road
emissions.
Ethylbenzene
xylenes
showed
equivalent
but
lower
backgrounds.
Peak
occurred
morning
evening
rush
hours,
linked
to
heating,
atmospheric
stagnation.
B/T
ranged
0.29
0.11
1.35
0.95,
X/E
1.75
0.91
3.68
0.30,
primary
pollution
local
followed
by
solvents,
coatings,
biomass
burning.
Lifetime
cancer
risk
exposure
was
below
definite
threshold
(10−4)
above
permissible
level
(10−6),
suggesting
moderate
particularly
areas.
Additionally,
health
index
at
generally
than
limit
value,
a
low
non-carcinogenic
overall.
offers
essential
insights
into
environments.
Chemometrics and Intelligent Laboratory Systems,
Journal Year:
2023,
Volume and Issue:
240, P. 104885 - 104885
Published: June 21, 2023
Over
the
past
decade,
Positive
Matrix
Factorization
(PMF)
has
become
most
commonly
used
tool
for
source
apportionment
of
air
pollutants
with
a
large
fraction
those
studies
using
implementation
developed
by
U.S.
Environmental
Protection
Agency
(EPA-PMF)
and
its
very
useful
diagnostic
tools.
During
same
period,
more
are
utilizing
monitoring
tools
that
provide
hourly
or
even
higher
time
resolution
data
leading
to
sets
(millions
points).
Because
nature
graphic
user
interface
in
EPA-PMF,
it
cannot
handle
than
approximately
half
million
points.
Thus,
alternative
approaches
needed
permit
these
larger
be
analyzed
still
able
outputs
better
interpretations
results.
We
have
protocol
use
multilinear
engine
(ME-2)
is
solver
EPA-PMF
make
such
analyses.
Here
we
report
how
this
approach
present
results
representative
set
particle
size
distributions
obtained
Rochester,
New
York
between
2008
2019.
Journal of Geophysical Research Atmospheres,
Journal Year:
2024,
Volume and Issue:
129(4)
Published: Feb. 21, 2024
Abstract
Understanding
sources
of
oxygenated
volatile
organic
compounds
(OVOCs)
in
the
atmosphere
still
has
large
uncertainties.
In
this
study,
an
improved
OVOC
source
apportionment
model
was
developed
by
principal
component
analysis
and
multiple
linear
regression
based
on
online
monitoring
nonmethane
hydrocarbons
(NMHCs)
OVOCs
a
dense
urban
agglomeration
winter.
The
modeled
concentrations
were
good
agreement
with
measured
(
R
2
=
0.56–0.97).
major
OVOCs,
except
for
2‐methylacrolein,
greatly
affected
anthropogenic
(15.8%–76.8%)
secondary
generation
(0.0%–51.7%),
while
transport
natural
contributed
to
0.0%–26.8%
0.0%–32.0%,
respectively.
selection
isoprene
as
tracer
led
underestimation
species
from
primary
emission
overestimation
sources.
addition,
photochemical
reactions
significantly
reduced
simulation
accuracy
NMHCs
afternoon,
0.60
±
0.23,
which
lower
than
overall
value
0.82
0.11.
However,
(0.83
0.14)
did
not
decrease
afternoon
due
compensation
oxidation.
Furthermore,
concentration
gradient
distribution
gradually
changes
normal
exponential
concentration,
influenced
degree
matching
between
change.
Developing
models
additional
tracers
at
different
levels
may
enhance
robustness
without
increasing
its
complexity.
