Abstract.
The
impacts
of
soot
particles
on
climate
and
human
health
depend
the
concentration
black
carbon
(BC)
as
well
thickness
composition
coating
material,
i.e.,
organic
inorganic
compounds
internally
mixed
with
BC.
In
this
study,
size-resolved
chemical
BC-containing
aerosol
was
measured
using
a
high-resolution
soot-particle
mass
spectrometer
(SP-AMS)
during
wintertime
in
Fresno,
California,
location
influenced
by
abundant
combustion
emissions
frequent
fog
events.
Concurrently,
particle
optical
properties
were
to
investigate
BC
absorption
enhancement.
Positive
matrix
factorization
(PMF)
analysis
performed
SP-AMS
spectral
measurements
explore
sources
atmospheric
processes
affecting
coatings.
revealed
that
residential
wood
burning
traffic
are
dominant
particles.
Alongside
primary
originating
from
biomass
(BBOABC)
vehicles
(HOABC)
two
distinct
types
processed
identified:
fog-related
oxidized
(FOOABC)
winter-background
OOABC
(WOOABC).
Both
showed
evidence
having
undergone
aqueous
processing,
albeit
differences.
FOOABC
substantially
elevated
events,
indicating
formation
secondary
(aqSOA)
within
droplets.
On
other
hand,
WOOABC
present
at
relatively
consistent
throughout
winter
is
likely
related
(SOA)
both
gas
phase
liquid
water.
By
comparing
temporal
variations
WOOABC,
we
gain
insights
into
key
aging
aerosol.
It
found
aqueous-phase
reactions
facilitated
droplets
had
significant
impact
coatings,
thereby
light
hygroscopic
These
findings
underscore
important
role
occurring
clouds
fogs
influencing
forcing
atmosphere.
Applied Sciences,
Journal Year:
2022,
Volume and Issue:
12(7), P. 3623 - 3623
Published: April 2, 2022
Airborne
particulate
matter
(PM)
is
a
pollutant
of
concern
not
only
because
its
adverse
effects
on
human
health
but
also
visibility
and
the
radiative
budget
atmosphere.
PM
can
be
considered
as
sum
solid/liquid
species
covering
wide
range
particle
sizes
with
diverse
chemical
composition.
Organic
aerosols
may
emitted
(primary
organic
aerosols,
POA),
or
formed
in
atmosphere
following
reaction
volatile
compounds
(secondary
SOA),
some
these
partition
between
gas
aerosol
phases
depending
upon
ambient
conditions.
This
review
focuses
carbonaceous
gaseous
precursors
by
road
traffic,
including
ultrafine
particles
(UFP)
polycyclic
aromatic
hydrocarbons
(PAHs)
that
are
clearly
linked
to
evolution
formation
species.
Clearly,
solid
fraction
has
been
reduced
during
last
two
decades,
implementation
after-treatment
systems
abating
approximately
99%
primary
mass
concentrations.
However,
role
brown
carbon
effect
climate
generation
nucleation
vapour
dilution
exhaust
remain
unclear
phenomena
will
need
further
investigation.
The
increasing
gasoline
vehicles
emissions
highlighted,
particularly
through
thermodynamic
gases
their
propensity
produce
particles.
remaining
carbon-containing
from
brakes,
tyres
wear
still
problem
even
future
full
electrification
vehicle
fleet.
Some
key
conclusions
recommendations
proposed
support
decision
makers
view
next
regulations
worldwide.
Atmospheric chemistry and physics,
Journal Year:
2022,
Volume and Issue:
22(12), P. 8073 - 8096
Published: June 22, 2022
Abstract.
Refractory
black
carbon
(rBC)
aerosols
play
an
important
role
in
air
quality
and
climate
change,
yet
highly
time-resolved
detailed
investigations
on
the
physicochemical
properties
of
rBC
its
associated
coating
are
still
scarce.
In
this
work,
we
used
a
laser-only
Aerodyne
soot
particle
aerosol
mass
spectrometer
(SP-AMS)
to
exclusively
measure
rBC-containing
(rBCc)
particles,
compared
their
with
those
total
nonrefractory
submicron
particles
(NR-PM1)
measured
parallel
by
high-resolution
AMS
(HR-AMS)
Shanghai.
Observations
showed
that,
overall,
was
thickly
coated,
average
ratio
core
(RBC)
∼5.0
(±1.7).
However,
rBC-coating
species
NR-PM1
only
19.1
(±4.9)
%;
sulfate
tended
condense
preferentially
non-rBC
so
7.4
(±2.2)
%,
while
majority
(72.7±21.0
%)
primary
organic
(POA)
were
rBC.
Positive
matrix
factorization
revealed
that
organics
emitted
from
cooking
did
not
coat
rBC,
portion
coated
biomass
burning;
such
unidentifiable
NR-PM1.
Small
rBCc
predominantly
traffic,
large-sized
ones
often
mixed
secondary
components
typically
had
thick
coating.
Sulfate
(SOA)
generated
mainly
through
daytime
photochemical
oxidation
(SOA
formation,
likely
situ
chemical
conversion
traffic-related
POA
SOA),
nocturnal
heterogeneous
formation
dominant
for
nitrate;
also
estimated
time
5–19
h
During
short
period
affected
ship
emissions,
characterized
as
having
high
vanadium
concentration
(on
6.3±3.1
ng
m−3)
mean
vanadium/nickel
2.0
(±0.6).
Furthermore,
size-resolved
hygroscopicity
parameter
(κrBCc)
obtained
based
full
characterization,
parameterized
κrBCc(x)=0.29–0.14
×
exp(-0.006×x)
(where
x
ranges
150
1000
nm).
Under
critical
supersaturations
(SSC)
0.1
%
0.2
D50
values
166
(±16)
110
(±5)
nm,
respectively,
16
(±3)
59
(±4)
number
could
be
activated
into
cloud
condensation
nuclei
(CCN).
Our
findings
valuable
advancing
understanding
BC
chemistry
well
effective
control
atmospheric
pollution.
Journal of Advances in Modeling Earth Systems,
Journal Year:
2024,
Volume and Issue:
16(1)
Published: Jan. 1, 2024
Abstract
Representing
mixing
state
of
black
carbon
(BC)
is
challenging
for
global
climate
models
(GCMs).
The
Community
Atmosphere
Model
version
6
(CAM6)
with
the
four‐mode
Modal
Aerosol
Module
(MAM4)
represents
aerosols
as
fully
internal
mixtures
uniform
composition
within
each
aerosol
mode,
resulting
in
high
degree
BC
non‐BC
species
and
large
mass
ratio
coating
to
(
R
,
BC‐containing
particles).
To
improve
representation,
we
coupled
a
machine
learning
(ML)
model
index
trained
on
particle‐resolved
simulations
CAM6
MAM4
(MAM4‐ML).
In
MAM4‐ML,
use
partition
accumulation
mode
particles
into
two
new
modes,
BC‐free
particles.
We
adjust
make
modeled
χ
)
match
one
predicted
by
ML
).
On
average,
fraction
decreases
from
100%
(MAM4‐default)
48%
globally
averaged
78%
63%
(MAM4‐ML,
19%
reduction)
agrees
well
(66%).
52%
better
observations.
hygroscopicity
drops
9%
leading
20%
reduction
activation
fraction.
surface
concentration
increases
most
(6.9%)
Arctic,
burden
4%,
globally.
Our
study
highlights
application
improving
key
processes
GCMs.
Atmospheric chemistry and physics,
Journal Year:
2024,
Volume and Issue:
24(7), P. 3953 - 3971
Published: April 3, 2024
Abstract.
A
high-resolution
soot
particle
aerosol
mass
spectrometer
(SP-AMS)
was
used
to
selectively
measure
refractory
black
carbon
(rBC)
and
its
associated
coating
material
using
both
the
ensemble
size-resolved
spectral
mode
event
trigger
single
(ETSP)
in
Houston,
Texas,
summer
2022.
This
study
conducted
as
part
of
Department
Energy
Atmospheric
Radiation
Measurement
(ARM)
program's
TRacking
Aerosol
Convection
interactions
ExpeRiment
(TRACER)
field
campaign.
The
revealed
an
average
(±1σ)
rBC
concentration
103
±
176
ng
m−3.
Additionally,
coatings
on
BC
particles
were
primarily
composed
organics
(59
%;
219
260
m−3)
sulfate
(26
94
55
m−3).
Positive
matrix
factorization
(PMF)
analysis
spectra
BC-containing
resolved
four
distinct
types
aerosol,
including
oxidized
organic
(OOABC,PMF)
factor
with
processed
primary
inorganic
(SO4,BC,PMF),
(O-BCPMF),
a
mixed
mineral
dust–biomass
burning
significant
contribution
from
potassium
(K-BBBC,PMF).
K-means
clustering
single-particle
identified
eight
different
clusters,
enriched
hydrocarbon-like
(HOABC,ETSP),
(SO4,BC,ETSP),
two
rBC,
OOA
(OOABC,ETSP),
chloride
(ClBC,ETSP),
nitrate
(NO3,BC,ETSP).
measurements
demonstrate
substantial
variation
thickness
coating-to-rBC
ratios
ranging
0.1
100.
mixing
state
index
(χ),
which
denotes
degree
homogeneity
varied
4
%
median
40
%,
indicating
that
population
lies
between
internal
external
but
has
large
temporal
source
type
variability.
In
addition,
fraction
particles,
majority
sulfate,
exhibit
sufficiently
high
κ
values
diameters
conducive
activation
cloud
nuclei
under
atmospherically
relevant
supersaturation
conditions.
finding
bears
significance
comprehending
aging
processes
rBC-containing
their
into
droplets.
Our
highlights
complex
nature
underscores
need
comprehend
variability
across
environments
for
accurate
assessment
climate
change.
Atmospheric chemistry and physics,
Journal Year:
2024,
Volume and Issue:
24(14), P. 8473 - 8488
Published: July 29, 2024
Abstract.
Aerosol
particles
play
critical
roles
in
climate
and
human
health.
However,
aerosol
composition
evolution,
particularly
secondary
organic
(SOA),
interactions
with
clouds
high-altitude
background
areas
China
remain
less
understood.
Here,
we
conducted
real-time
measurements
of
submicron
aerosols
(PM1)
using
mass
spectrometers
at
a
forested
mountain
site
(1128
m
a.s.l.)
southeastern
November
2022.
The
average
(±1σ)
PM1
concentration
was
4.3±4.8
µg
m−3,
which
ubiquitously
lower
than
that
other
sites
China.
Organic
(OA)
constituted
the
largest
fraction
(42.9
%)
predominantly
secondary,
as
indicated
by
high
oxygen-to-carbon
(O
/
C)
ratio
(0.85–0.96)
carbon
oxidation
state
(0.21–0.49).
Notably,
remarkably
enhanced
concentrations
observed
during
daytime
on
cloudless
days
were
identified
to
be
likely
produced
from
cloud
evaporation.
While
more
oxidized
oxygenated
OA
scavenged
efficiently
events,
evaporation
found
release
significant
amount
air
masses
transported
polluted
regions.
distinct
decrease
ΔCO
increase
O
C
evaporative
period
further
demonstrates
remaining
droplets
is
generally
moderate
state.
Moreover,
nitrates
also
estimated
showed
higher
contribution
total
nitrate
cloudy
(27
(3
%).
Overall,
our
results
demonstrate
importance
SOA
influences
processes
regional
Atmospheric chemistry and physics,
Journal Year:
2024,
Volume and Issue:
24(14), P. 8507 - 8518
Published: July 30, 2024
Abstract.
The
investigation
of
the
water-soluble
characteristics
secondary
organic
carbon
(SOC)
is
essential
for
a
more
comprehensive
understanding
its
climate
effects.
However,
due
to
limitations
existing
source
apportionment
methods,
water
solubility
different
types
SOC
remains
uncertain.
This
study
analyzed
stable
isotope
and
mass
spectral
signatures
total
(TC)
(WSOC)
in
ambient
PM2.5
samples
1
year
established
profiles
fresh
aged
SOC.
Furthermore,
Bayesian
mixing
(BSIM)
model
was
employed
reveal
coastal
megacity
China.
WSOC
dominated
by
sources,
with
contributing
28.1
%
45.2
%,
respectively.
Water-insoluble
(WIOC)
primary
which
contributed
23.2
13.4
%.
We
also
found
that
aging
degree
has
considerable
impacts
on
much
higher
fraction
(76.5
%)
compared
(54.2
%).
Findings
this
may
provide
new
perspective
further
hygroscopicity
effects
degrees
light
extinction
change.
Atmospheric chemistry and physics,
Journal Year:
2023,
Volume and Issue:
23(23), P. 15039 - 15056
Published: Dec. 7, 2023
Abstract.
The
impacts
of
soot
particles
on
climate
and
human
health
depend
the
concentration
black
carbon
(BC)
as
well
thickness
composition
coating
material,
i.e.,
organic
inorganic
compounds
internally
mixed
with
BC.
In
this
study,
size-resolved
chemical
BC-containing
aerosol
was
measured
using
a
high-resolution
particle
mass
spectrometer
(SP-AMS)
during
wintertime
in
Fresno,
California,
location
influenced
by
abundant
combustion
emissions
frequent
fog
events.
Concurrently,
optical
properties
were
to
investigate
BC
absorption
enhancement.
Positive
matrix
factorization
(PMF)
analysis
performed
SP-AMS
spectral
measurements
explore
sources
atmospheric
processes
affecting
coatings.
revealed
that
residential
woodburning
traffic
are
dominant
particles.
Alongside
primary
originating
from
biomass
burning
(BBOABC)
vehicles
(HOABC)
two
distinct
types
processed
identified:
fog-related
oxidized
(FOOABC)
winter-background
OOABC
(WOOABC).
Both
showed
evidence
having
undergone
aqueous
processing,
albeit
differences.
FOOABC
substantially
elevated
events,
indicating
formation
secondary
(aqSOA)
within
droplets.
On
other
hand,
WOOABC
present
at
relatively
consistent
throughout
winter
likely
related
(SOA)
both
gas
phase
liquid
water.
By
comparing
temporal
variations
WOOABC,
we
gain
insights
into
key
aging
aerosol.
It
found
aqueous-phase
reactions
facilitated
droplets
had
significant
impact
coatings,
thereby
light
hygroscopic
These
findings
underscore
important
role
occurring
clouds
fogs
influencing
forcing
atmosphere.
