Atmospheric chemistry and physics,
Journal Year:
2020,
Volume and Issue:
20(1), P. 223 - 241
Published: Jan. 6, 2020
Abstract.
A
torrential
rainfall
case,
which
happened
in
Guangdong
Province
during
14–16
December
2013,
broke
the
historical
record
province
terms
of
duration,
affected
area,
and
accumulative
precipitation.
The
influence
anthropogenic
aerosols
on
this
extreme
event
is
examined
using
a
coupled
meteorology–chemistry–aerosol
model.
Up
to
33.7
mm
precipitation
enhancement
estuary
near
coast
mainly
attributed
aerosol–cloud
interactions
(ACI),
whereas
aerosol–radiation
interaction
partially
offsets
14
%
increase.
Our
further
analysis
changes
hydrometeors
latent
heat
sources
suggests
that
ACI
effects
intensification
can
be
divided
into
two
stages:
cold
rain
former
stage
followed
by
warm
latter.
Responses
aerosol
concentration
from
local
(i.e.,
Province)
remote
outside
are
also
investigated
through
simulations
with
reduced
emissions
either
or
sources.
Accumulated
aggregates
ground
surface
dilutes
quickly
after
initiated.
By
contrast,
extend
up
8
km
above
last
much
longer
before
decreasing
until
peak
begins,
because
continuously
transported
strong
northerly
winds.
patterns
response
concentrations
resemble
each
other.
However,
compared
enhancement,
contribute
more
than
twice
increase
intensifying
both
rain,
occupying
predominant
role.
10-time
emission
sensitivity
test
shows
about
10
times
PM2.5
control
run.
Cold
(warm)
drastically
enhanced
(suppressed)
10×
In
emissions,
pattern
cloud
property
resembles
differences
between
CTL
CLEAN,
but
greater
magnitude.
average
over
decreases
1.0
run
increases
1.4
CLEAN
We
note
concentrated
within
narrowed
downstream
region
source,
decrease
dispersed
across
upstream
region.
This
indicates
excessive
not
only
suppress
rainfall,
change
spatial
distribution
precipitation,
increasing
range,
thereby
potentially
exacerbating
flood
drought
elsewhere.
study
highlights
importance
considering
meteorology
improve
weather
forecasting.
Furthermore,
may
outweigh
those
convective
invigoration
effect.
Environment International,
Journal Year:
2020,
Volume and Issue:
139, P. 105558 - 105558
Published: April 8, 2020
Air
pollution
over
China
has
attracted
wide
interest
from
public
and
academic
community.
PM2.5
is
the
primary
air
pollutant
across
China.
Quantifying
interactions
between
meteorological
conditions
concentrations
are
essential
to
understand
variability
of
seek
methods
control
PM2.5.
Since
2013,
measurement
been
widely
made
at
1436
stations
country
more
than
300
papers
focusing
on
PM2.5-meteorology
have
published.
This
article
a
comprehensive
review
impact
concentrations.
We
start
with
an
introduction
general
China,
then
seasonal
spatial
variations
influences
Next,
major
used
quantify
checked
compared.
find
that
causality
analysis
suitable
for
extracting
influence
individual
factors
whilst
statistical
models
good
quantifying
overall
effect
multiple
Chemical
Transport
Models
(CTMs)
potential
provide
dynamic
estimation
by
considering
anthropogenic
emissions
transport
evolution
pollutants.
comprehensively
examine
mechanisms
how
may
concentrations,
including
dispersion,
growth,
chemical
production,
photolysis,
deposition
The
feedback
effects
also
carefully
examined.
Based
this
review,
suggestions
future
research
approaches
mitigating
finally.
Atmospheric measurement techniques,
Journal Year:
2018,
Volume and Issue:
11(11), P. 6107 - 6135
Published: Nov. 12, 2018
Abstract.
The
Cloud-Aerosol
Lidar
with
Orthogonal
Polarization
(CALIOP)
version
4.10
(V4)
level
2
aerosol
data
products,
released
in
November
2016,
include
substantial
improvements
to
the
subtyping
and
lidar
ratio
selection
algorithms.
These
are
described
along
resulting
changes
optical
depth
(AOD).
most
fundamental
change
V4
products
is
a
new
algorithm
identify
subtypes
stratosphere.
Four
introduced
for
stratospheric
aerosols:
polar
(PSA),
volcanic
ash,
sulfate/other,
smoke.
tropospheric
was
also
improved
by
adding
following
enhancements:
(1)
all
now
allowed
over
regions,
whereas
3
(V3)
only
clean
continental
polluted
aerosols;
(2)
“dusty
marine”
subtype
introduced,
representing
mixtures
of
dust
marine
aerosols
near
ocean
surface;
(3)
“polluted
continental”
“smoke”
have
been
renamed
continental/smoke”
“elevated
smoke”,
respectively.
revises
ratios
marine,
dust,
continental,
elevated
smoke
subtypes.
As
consequence
updates,
mean
532
nm
AOD
retrieved
CALIOP
has
increased
0.044
(0.036)
or
52
%
(40
%)
nighttime
(daytime).
revisions
influential
factor
from
V3
V4,
especially
cloud-free
skies.
Preliminary
validation
studies
show
that
discrepancies
between
AERONET–MODIS
(ocean)
reduced
compared
V3.
Geophysical Research Letters,
Journal Year:
2019,
Volume and Issue:
46(11), P. 6080 - 6089
Published: May 24, 2019
Abstract
The
knowledge
regarding
how
the
boundary
layer
height
(BLH)
changes
over
time
is
still
poor.
Here
we
analyze
spatial
and
temporal
in
radiosonde‐derived
measurements
of
BLH
China
from
1979
to
2016.
A
qualitatively
robust
abrupt
change
occurred
2004.
Over
former
period
(from
2003)
a
spatially
uniform
increase
was
found
BLH,
while
latter
decreased
nonuniform
way.
Second,
meteorological
influence
on
rising
determined
have
negative
association
with
soil
moisture,
lower
tropospheric
stability
relative
humidity,
positive
near‐surface
temperature.
Yet,
there
different
meteorology
period,
where
revealed
T
sfc
humidity.
These
findings
shed
new
light
long‐term
air
pollution
across
China.
Current Pollution Reports,
Journal Year:
2019,
Volume and Issue:
5(4), P. 261 - 271
Published: Sept. 9, 2019
Abstract
Purpose
of
Review
During
the
past
decades,
number
and
size
megacities
have
been
growing
dramatically
in
China.
Most
Chinese
are
suffering
from
heavy
PM
2.5
pollution.
In
pollution
formation,
planetary
boundary
layer
(PBL)
plays
an
important
role.
This
review
is
aimed
at
presenting
current
state
understanding
PBL-PM
interaction
megacities,
as
well
to
identify
main
gaps
knowledge
further
research
needs.
Recent
Findings
The
PBL
critical
formation
urban
multiple
temporal
scales,
ranging
diurnal
change
seasonal
variation.
For
essential
structure/process
pollution,
coastal
different
concerns
mountainous
or
land-locked
megacities.
cities,
recirculation
induced
by
sea-land
breeze
can
accumulate
pollutants,
whereas
valley/basin,
blocking
effects
terrains
lead
stagnant
conditions
thermal
inversion.
Within
a
megacity,
although
urbanization-induced
land
use
cause
thermodynamic
perturbations
facilitate
development
PBL,
increases
emissions
outweigh
this
impact,
resulting
net
increase
aerosol
concentration.
Moreover,
radiative
modify
heating
upper
layers
reducing
surface
heat
flux,
suppressing
exacerbating
Summary
presented
13
with
various
geographic
elucidated
influencing
processes.
To
understand
complicated
interactions,
long-term
observations
meteorology
properties
multi-layers
need
be
implemented.
Earth and Space Science,
Journal Year:
2019,
Volume and Issue:
6(5), P. 887 - 901
Published: April 30, 2019
Abstract
The
observed
relationships
between
boundary
layer
height
(BLH)
and
PM
2.5
on
a
national
scale
remain
unclear
due
to
the
dearth
of
observations.
Here
we
investigated
this
relationship
from
unique
perspective
thermodynamic
stability
in
planetary
(PBL),
using
summertime
(June–August)
soundings
China
for
period
2014
2017.
For
all
three
times
(0800,
1400,
2000
Beijing
time
[BJT]),
positive
(negative)
concentrations
anomalies
were
found
correlate
with
negative
(positive)
BLHs
relative
daily
means.
correlation
was
strongest
at
1400
BJT,
followed
by
BJT
0800
BJT.
Overall,
nonuniformly
anticorrelate
BLH
across
anticorrelation
occurred
North
Plain
sharp
contrast
much
weaker
other
regions
characterized
less
polluted
regions.
averaged
neutral
layers
higher
than
that
convective
(CBLs).
CBL,
where
strongest,
conducive
dissipating
more
aerosol
heavily
area
layer.
CBL
formed
under
low
cloud
cover,
surface
humidity,
strong
wind
speed
favorable
dispersion
aerosol,
stable
happen
highest
cover.
Also,
seen
.
findings
call
attention
thermodynamical
condition
PBL
should
be
considered
when
examining
aerosol‐PBL
interactions.
Journal of Geophysical Research Atmospheres,
Journal Year:
2019,
Volume and Issue:
124(16), P. 9609 - 9623
Published: July 29, 2019
Abstract
Previous
studies
have
reported
boundary
layer
features
related
to
air
pollution.
However,
few
comprehensively
evaluated
the
characteristics
and
mechanisms
of
vertical
wind
in
formation
evolution
heavy
particulate
matter
pollution
episodes
(EP)
Hong
Kong.
In
this
study,
we
analyzed
(PM)
pollutions
over
Kong
their
relationships
with
profiles
using
high‐time‐resolution
Doppler
lidar
measurements
hourly
meteorological
quality
observations.
We
identified
nine
EPs
show
that
events
were
closely
coupled
various
planetary
(PBL).
Our
analysis
suggests
strong
speed
shear
at
certain
heights
PBL
had
a
positive
correlation
surface
PM
during
most
superregional
transboundary
EPs.
The
maximum
transport
height
extends
from
about
2.0
km
or
even
higher;
these
differed
among
regional
At
peak
concentrations
EPs,
10
significant
negative
heights/mixing
heights,
while
averaged
was
significantly
positively
correlated.
These
different
mixing
mainly
driven
by
conditions
under
weather
systems
high
pressure,
cold
fronts,
dust
storms,
typhoons.
This
work
provides
scientific
evidence
pollutions.
Journal of Geophysical Research Atmospheres,
Journal Year:
2019,
Volume and Issue:
124(4), P. 2210 - 2234
Published: Feb. 8, 2019
Abstract
The
knowledge
of
mesoscale
convective
system
(MCS)
in
the
Asian
monsoon
region
remains
still
deficient
due
to
limited
available
data
and
less
powerful
algorithms.
Here,
using
from
Advanced
Himawari
Imager
onboard
Himawari‐8
(HW8),
an
improved
algorithm
combining
area
overlapping
with
Kalman
filter
is
developed,
which
captures
much
smaller
MCSs
that
are
unavailable
otherwise.
Several
influential
factors
like
rate
splitting/merging
method,
initial
state
variable
all
were
appreciated,
handled
explicitly.
occurrence
frequency,
moving
trajectory
two
types
MCS,
including
ordinary
MCS
superconvective
system,
has
been
comprehensively
examined
for
warm
season
(April
September)
2016.
Comparison
analyses
ground
precipitation
radar
measurements
confirm
good
performance
our
algorithm.
In
particular,
direction
strongly
depends
on
latitudes,
so
does
horizontal
velocity.
Compared
over
ocean,
frequency
dominates
land
or
along
coasts
tropics,
where
strong
moisture
flux
convergence
frequently
observed
low
troposphere.
addition,
detected
eastern
China
can
roughly
capture
meridional
propagation
time,
corresponds
well
belts
linked
Meiyu
front
systems.
systems
dominate
Bay
Bengal
South
Sea
large‐scale
circulation.
Our
findings
provide
new
insights
spatiotemporal
patterns
during
region.
