Abstract.
Understanding
the
spatiotemporal
characteristics
of
long-
and
short-term
exposure
to
ground
ozone
is
crucial
for
improving
environmental
management
health
studies.
However,
such
studies
have
been
constrained
by
availability
high-resolution
data.
To
address
this,
we
characterized
ground-level
variations
risks
across
multiple
spatial
(pixel,
county,
region,
national)
temporal
(daily,
monthly,
seasonal,
annual)
scales
using
daily
1-km
data
from
2000
2020,
derived
satellite
LST
via
a
machine-learning
method.
The
model
provided
reliable
estimates,
validated
through
rigorous
cross-validation
direct
comparison
with
external
measurements.
Our
long-term
estimates
revealed
seasonal
shifts
in
high-exposure
centers:
spring
eastern
China,
summer
North
China
Plain
(NCP),
autumn
Pearl
River
Delta
(PRD).
A
non-monotonous
trend
was
observed,
levels
rising
2001–2007
at
rate
0.47
μg/m3/year,
declining
after
2008
(-0.58
μg/m3/year),
increasing
significantly
2016–2020
(1.16
accompanied
regional
fluctuations.
Notably,
increased
0.63
μg/m3/year
NCP
during
second
phase,
6.38
PRD
third
phase.
Exposure
over
100
μg/m3
shifted
June
May,
exceeding
160
were
primarily
seen
NCP,
showing
an
expanding
trend.
day-to-day
analysis
highlights
influence
meteorological
factors
on
extreme
events.
These
findings
emphasize
need
stronger
mitigation
efforts.
Environmental Science & Technology,
Год журнала:
2024,
Номер
58(36), С. 15938 - 15948
Опубликована: Авг. 28, 2024
Accurately
mapping
ground-level
ozone
concentrations
at
high
spatiotemporal
resolution
(daily,
1
km)
is
essential
for
evaluating
human
exposure
and
conducting
public
health
assessments.
This
requires
identifying
understanding
a
proxy
that
well-correlated
with
variation
available
high-resolution
data.
study
introduces
modeling
method
utilizing
the
XGBoost
algorithm
satellite-derived
land
surface
temperature
(LST)
as
primary
predictor.
Focusing
on
China
in
2019,
our
model
achieved
cross-validation
Sustainability,
Год журнала:
2023,
Номер
16(1), С. 123 - 123
Опубликована: Дек. 22, 2023
Surface
ozone
pollution
in
China
has
been
persistently
becoming
worse
recent
years;
therefore,
it
is
of
great
importance
to
accurately
estimate
and
explore
the
spatiotemporal
variations
surface
East
China.
By
using
S5P-TROPOMI-observed
NO2,
HCHO
data
(7
km
×
3.5
km),
other
surface-ozone-influencing
factors,
including
VOCs,
meteorological
data,
NOX
emission
inventory,
NDVI,
DEM,
population,
land
use
cover,
hourly
situ
observations,
an
extreme
gradient
boosting
model
was
used
daily
0.05°
gridded
maximum
average
8
h
(MDA8)
during
2019–2021.
Four
estimation
models
were
established
by
combining
NO2
from
S5P-TROPOMI
observations
CAMS
reanalysis
data.
The
sample-based
validation
R2
values
these
four
all
larger
than
0.92,
while
their
site-based
0.82.
results
revealed
that
coverage
ratio
highest
(100%),
second
(96.26%).
Furthermore,
MDA8
two
averaged
produce
final
dataset.
It
indicated
O3
2019–2021
susceptible
anthropogenic
precursors
such
as
VOCs
(22.55%)
(8.97%),
well
factors
(27.35%)
wind
direction,
temperature,
speed.
Subsequently,
patterns
analyzed.
Ozone
mainly
concentrated
North
Plain
(NCP),
Pearl
River
Delta
(PRD),
Yangtze
(YRD).
Among
three
regions,
NCP
occurs
June
(summer),
YRD
May
(spring),
PRD
April
(spring)
September
(autumn).
In
addition,
concentration
decreased
3.74%
2020
compared
2019,
which
may
have
influenced
COVID-19
epidemic
implementation
policy
synergistic
management
PM2.5
pollution.
regions
mostly
affected
(−2~−8%),
Middle
Lower
(−6~−10%),
(−4~−10%).
Overall,
estimated
2019
2021
provides
a
promising
source
analysis
basis
for
related
researchers.
Meanwhile,
reveals
spatial
temporal
main
influencing
good
control
pollution,
also
technical
support
sustainable
development
environment
Applied Sciences,
Год журнала:
2024,
Номер
14(12), С. 5026 - 5026
Опубликована: Июнь 9, 2024
Over
the
past
decade,
surface
ozone
has
emerged
as
a
significant
air
pollutant
in
China,
especially
North
China
Plain
(NCP).
For
effective
management
NCP,
it
is
crucial
to
accurately
estimate
levels
and
identify
primary
influencing
factors
for
pollution
this
region.
This
study
utilized
precursors
such
volatile
organic
compounds
(VOCs)
nitrogen
oxides
(NOX),
meteorological
data,
land
cover,
normalized
difference
vegetation
index
(NDVI),
terrain,
population
data
build
an
extreme
gradient
boosting
(XGBoost)-based
estimation
model
NCP
during
2019
2021.
Four
models
were
developed
using
different
NO2
formaldehyde
(HCHO)
datasets
from
Sentinel-5
TROPOMI
observations
Copernicus
Atmosphere
Monitoring
Service
(CAMS)
reanalysis
data.
Site-based
validation
results
of
these
four
showed
high
accuracy
with
R2
values
above
0.86.
Among
models,
two
higher
spatial
coverage
ratio
selected,
their
averaged
produce
final
products.
The
indicated
that
VOCs
NOX
main
pollutants
causing
relative
contributions
accounted
more
than
23.34%
10.23%,
respectively,
while
HCHO
also
played
role,
contributing
over
5.64%.
Additionally,
had
notable
impact,
28.63%
pollution,
each
individual
factor
2.38%.
distribution
identified
Hebei–Shandong–Henan
junction
hotspot,
peak
occurring
summer,
particularly
June.
Therefore,
hotspot
region
promoting
reduction
NOx
can
play
important
role
mitigation
O3
improvement
quality
Authorea (Authorea),
Год журнала:
2024,
Номер
unknown
Опубликована: Июль 14, 2024
Surface
ozone
(O3)
has
become
a
primary
pollutant
affecting
urban
air
quality
and
public
health
in
China.To
address
this
concern,
we
developed
nation-wide
surface
maximum
daily
average
8-h
(MDA8)
O3
concentration
dataset
for
China
(ChinaHighO3)
at
10-km
resolution
since
2013
which
been
widely
employed
wide
range
studies.To
meet
the
increasing
demand
its
usage,
have
made
significant
enhancements,
including
development
of
more
advanced
deep
learning
model
incorporation
major
source
updates,
such
as
1
km
downward
solar
radiation
temperature
directly
from
satellite
retrievals.Additionally,
extend
temporal
coverage
dating
back
to
2000,
increase
spatial
km,
most
importantly,
notably
improve
data
(with
5%
cross-validation
coefficient
determination
an
11.2%
decrease
root-mean-square
error
compared
previous
dataset).Using
substantially
improved
new
product,
analyzed
found
some
dynamic
diverse
patterns
national
levels
over
past
two
decades.The
annual
mean
shown
relative
stability
2000
2015,
followed
by
sharp
increase,
reaching
peak
values
2019,
subsequently
declining.Additionally,
observed
large
difference
13%
peak-season
concentrations
between
rural
regions
China.This
disparity
significantly
increased
particularly
Beijing-Tianjin-Hebei
Pearl
River
Delta
regions.Notably,
nearly
all
population
across
(>
99.5%)
resided
areas
exposed
pollution
exceeding
World
Health
Organization
(WHO)
recommended
long-term
guideline
(AQG)
level
[peak-season
MDA8
>
60
μg/m
3
]
2000.Moreover,
short-term
population-risk
exposure
showed
trend
1.19%
(p
<
0.001)
days
WHO's
AQG
(daily
=
100
)
per
year
during
22-year
period
considered
here.The
overall
upward
(0.93
±
0.19
/yr,
p
led
exceptionally
rate
964
(95%
confidence
interval:
492,
1303)
premature
deaths
2000-2021
China.Urgent
action
is
required
develop
comprehensive
strategies
aimed
mitigating
enhanced
future.