Abstract.
The
vertical
distribution
of
black
carbon
(BC)
as
well
its
mixing
state
is
great
concern
due
to
BC’s
strong
regional
climatic
and
environmental
effects.
In
this
study,
measurements
were
conducted
through
a
moveable
container
based
on
meteorology
tower
in
an
urban
area.
A
total
112
profiles
(0–240
m),
including
the
concentrations
BC,
O3,
NOx
optical
properties
aerosols,
obtained.
Based
BC
concentration,
could
be
classified
into
four
categories:
uniform,
gradual
decrease,
sharp
sudden
increase.
uniform
type
indicates
with
similar
pollutant
along
direction.
gradual/sharp
decrease
types
indicate
stable
conditions
higher
ground
lower
at
altitudes.
Due
radiation
summer,
exhibited
clear
diurnal
variation
which
~80
%
during
daytime
~40
%–90
night.
O3
exception,
concentration
generally
increases
height
even
under
conditions.
size
core
varied
slightly
direction,
coating
thickness,
denoted
by
shell/core
ratio
(Dp/Dc),
increased
Although
thickness
increase
absorption
ability
average
enhancement
1.25
23:00,
difference
Dp/Dc
(2
%)
was
much
than
that
(~35
%).
mainly
caused
concentration.
addition,
occasionally
6:00–8:00
but
remained
8:00–10:00.
Vertical
transportation
from
upper
heights,
such
residual
layer,
significantly
influence
surface
early
mornings.
This
study
exhibits
continuous
picture
areas,
would
helpful
for
understanding
effect.
Atmospheric chemistry and physics,
Год журнала:
2023,
Номер
23(9), С. 5517 - 5531
Опубликована: Май 17, 2023
Abstract.
Reliable
observations
of
aerosol
optical
properties
are
crucial
for
quantifying
the
radiative
forcing
climate.
The
simultaneous
measurements
at
three
wavelengths
PM1
and
PM10
were
conducted
in
urban
Beijing
from
March
2018
to
February
2022.
absorption
coefficient
(σab)
550
nm
decreased
by
55.0
%
53.5
2021.
significant
reduction
σab
may
be
related
reduced
primary
emissions
caused
effective
air
pollution
control
measures.
PM2.5
mass
concentration
34.4
Single
scattering
albedo
(SSA)
increased
0.89±0.04
(0.87±0.05
PM1)
0.93±0.03
(0.91±0.04
Increasing
SSA
decreasing
suggest
that
fraction
absorbing
aerosols
with
improved
quality
due
measures
being
taken.
annual
average
submicron
ratio
(Rab)
86.1
89.2
2021,
suggesting
fine
particles
main
contributors
total
contribution
became
more
important.
Ångström
exponent
(AAE)
winter
implying
a
brown
carbon
light
absorption,
which
relate
biomass
burning
coal
combustion.
During
study
period,
efficiency
negative,
mainly
influenced
increasing
was
−27.0
−26.2
W
m−2
per
depth
(AOD)
Higher
concentrations
primarily
distributed
clusters
4
5,
transported
south
west
each
year.
corresponding
5
evidently
result
source
surrounding
regions
Beijing.
4-year
data
presented
this
provide
critical
parameters
assessment
within
two
size
ranges
helpful
evaluating
effectiveness
clean
action.
Atmospheric chemistry and physics,
Год журнала:
2023,
Номер
23(12), С. 7225 - 7239
Опубликована: Июнь 30, 2023
Abstract.
The
vertical
distribution
of
black
carbon
(BC),
as
well
its
mixing
state,
is
great
concern
due
to
BC's
strong
regional
climatic
and
environmental
effects.
In
this
study,
measurements
were
conducted
through
a
moveable
container
based
on
meteorological
tower
in
the
Beijing
urban
area
during
June
July.
A
total
112
profiles
(0–240
m),
including
concentrations
BC,
O3,
NOx
optical
properties
aerosols,
obtained.
Based
BC
concentration,
could
be
classified
into
four
categories:
uniform,
gradual
decrease,
sharp
decrease
sudden
increase.
uniform
type
indicates
with
similar
pollutant
along
direction.
types
indicate
stable
conditions
higher
ground
lower
at
altitudes.
Due
radiation
summer,
exhibited
clear
diurnal
variation
which
∼
80
%
daytime
40
%–90
night.
O3
an
exception,
concentration
generally
increases
height,
even
under
conditions.
size
core
varied
slightly
direction,
coating
thickness,
denoted
by
diameter
ratio
between
BC-containing
particle
(Dp/Dc),
increased
height
Although
thickness
increase
absorption
ability
average
enhancement
1.25
23:00
LT
(local
time:
UTC+8),
difference
Dp/Dc
(2
%)
was
much
than
that
(∼
35
%).
mainly
caused
concentration.
addition,
occasionally
06:00–08:00
but
remained
08:00–10:00.
Vertical
transportation
from
upper
heights,
such
residual
layer,
significantly
influence
surface
early
mornings.
This
study
exhibits
continuous
picture
state
areas,
would
helpful
for
understanding
effect.
Atmospheric Pollution Research,
Год журнала:
2023,
Номер
15(2), С. 101992 - 101992
Опубликована: Ноя. 20, 2023
The
atmospheric
pollution
burden
in
Bangkok,
Thailand,
is
likely
to
be
similar
that
of
other
large
urban
agglomerations.
Black
carbon
(BC)
aerosol
one
the
key
components
PM2.5
(particulate
matter
with
equivalent
diameter
≤2.5
μm)
pollutants;
jointly
they
adversely
affect
humans
and
environment.
This
study
assessed
BC
ambient
concentrations
Bangkok
over
nine
months
(November
1,
2020,
July
27,
2021),
focusing
on
seasonal
differences
during
haze
period
(Hp;
december
2020
February
2021)
non-haze
(NHP;
remaining
months).
data
were
measured
optically,
together
filter
sampling
particles
at
heights
30,
75,
110
m
above
ground
level
(AGL).
A
thermal/optical
analysis
method
was
used
determine
mass
collected
samples.
results
showed
vertically
averaged
concentration
within
increased
more
than
3-fold
from
2.82
9.09
μg/m3
NHP
HP.
vertical
dependence
characterized
by
an
increase
height
AGL
NHP.
In
contrast,
opposite
trend
observed
for
average
values
PM2.5/BC
ratio
all
a
trend,
accounting
25%
peak
season.
Journal of Geophysical Research Atmospheres,
Год журнала:
2024,
Номер
129(14)
Опубликована: Июль 20, 2024
Abstract
Aerosol
single‐scattering
albedo
(SSA)
is
the
most
critical
factor
for
accurately
calculating
of
aerosol
radiative
effects,
however,
observation
vertical
profiles
SSA
difficult
to
realize.
Current
assessments
effects
remain
uncertain
because
lack
long‐term,
high‐resolution
observations.
High‐resolution
were
observed
in
a
semi‐arid
region
Northwest
China
during
winter
using
tethered
balloon.
The
used
calculate
direct
forcing
and
heating
rates.
Significant
differences
calculated
found
(e.g.,
48.3%
relative
difference
effect
atmosphere
at
14:00)
between
constant
assumption
with
=
0.90.
Diurnal
variations
distribution
decisively
influenced
aerosols.
Furthermore,
absorbing
aerosols
meteorological
parameters
provide
robust
observational
evidence
an
elevated
layer.
This
study
provides
more
accurate
calculation
profiles.
Abstract.
The
vertical
distribution
of
black
carbon
(BC)
as
well
its
mixing
state
is
great
concern
due
to
BC’s
strong
regional
climatic
and
environmental
effects.
In
this
study,
measurements
were
conducted
through
a
moveable
container
based
on
meteorology
tower
in
an
urban
area.
A
total
112
profiles
(0–240
m),
including
the
concentrations
BC,
O3,
NOx
optical
properties
aerosols,
obtained.
Based
BC
concentration,
could
be
classified
into
four
categories:
uniform,
gradual
decrease,
sharp
sudden
increase.
uniform
type
indicates
with
similar
pollutant
along
direction.
gradual/sharp
decrease
types
indicate
stable
conditions
higher
ground
lower
at
altitudes.
Due
radiation
summer,
exhibited
clear
diurnal
variation
which
~80
%
during
daytime
~40
%–90
night.
O3
exception,
concentration
generally
increases
height
even
under
conditions.
size
core
varied
slightly
direction,
coating
thickness,
denoted
by
shell/core
ratio
(Dp/Dc),
increased
Although
thickness
increase
absorption
ability
average
enhancement
1.25
23:00,
difference
Dp/Dc
(2
%)
was
much
than
that
(~35
%).
mainly
caused
concentration.
addition,
occasionally
6:00–8:00
but
remained
8:00–10:00.
Vertical
transportation
from
upper
heights,
such
residual
layer,
significantly
influence
surface
early
mornings.
This
study
exhibits
continuous
picture
areas,
would
helpful
for
understanding
effect.
