International Journal of Environmental Research and Public Health,
Год журнала:
2022,
Номер
19(3), С. 1718 - 1718
Опубликована: Фев. 2, 2022
In
2020,
the
first
case
of
COVID-19
was
confirmed
in
Korea,
and
social
distancing
implemented
to
prevent
its
spread.
This
reduced
movement
people,
changes
air
quality
were
expected
owing
emissions.
present
paper,
impact
traffic
volume
change
caused
by
on
Seoul,
is
examined.
Two
regression
analyses
performed
using
generalized
additive
model
(GAM),
assuming
a
Gaussian
distribution;
relationships
between
(1)
number
cases
2020–2021
rate
(2)
Seoul
from
2016
2019
analyzed.
The
results
show
that
decreased
0.00431%
per
case;
when
fell
1%,
PM10,
PM2.5,
CO,
NO2,
O3,
SO2
concentrations
0.48%,
0.94%,
0.39%,
0.74%,
0.16%,
−0.01%,
respectively.
mechanism
accounts
for
improvements
O3
during
2020–2021.
From
these
results,
majority
reduction
pollutant
appears
be
result
long-term
declining
trend
rather
than
COVID-19.
Environmental Pollution,
Год журнала:
2021,
Номер
288, С. 117783 - 117783
Опубликована: Июль 16, 2021
The
Central
Plains
Economic
Region
(CPER)
located
along
the
transport
path
to
Beijing-Tianjin-Hebei
area
has
experienced
severe
PM2.5
pollution
in
recent
years.
However,
few
modeling
studies
have
been
performed
on
sources
of
PM2.5,
especially
impacts
emission
reduction
strategies.
In
this
study,
Nested
Air
Quality
Prediction
Model
System
(NAQPMS)
with
an
online
tracer-tagging
module
was
adopted
investigate
source
sectors
and
a
series
sensitivity
tests
were
conducted
different
sector-based
mitigation
strategies
pollution.
response
surfaces
pollutants
changes
built.
results
showed
that
resident-related
sector
(resident
agriculture),
fugitive
dust,
traffic
industry
emissions
main
Zhengzhou,
contributing
49%,
19%,
15%
13%,
respectively.
Response
Henan
revealed
combined
efficiently
decreased
Zhengzhou.
reduced
only
region
barely
satisfied
national
air
quality
standard
75
μg/m3,
whereas
50%–60%
over
whole
could
reach
goal.
On
severely
polluted
days,
even
60%
these
two
insufficient
satisfy
μg/m3.
Moreover,
resulted
increase
O3
concentration.
surface
method
Zhengzhou
by
19%
COVID-19
lockdown,
which
approached
observed
21%,
indicating
be
employed
study
lockdown
This
provides
scientific
reference
for
formulation
CPER.
Remote Sensing,
Год журнала:
2023,
Номер
15(5), С. 1295 - 1295
Опубликована: Фев. 26, 2023
The
lockdowns
from
the
coronavirus
disease
of
2019
(COVID-19)
have
led
to
a
reduction
in
anthropogenic
activities
and
hence
reduced
primary
air
pollutant
emissions,
which
were
reported
helped
quality
improvements.
However,
expressed
by
index
(AQI)
did
not
improve
Shanghai,
China,
during
COVID-19
outbreak
spring
2022.
To
better
understand
reason,
we
investigated
variations
nitrogen
dioxide
(NO2),
ozone
(O3),
PM2.5
(particular
matter
with
an
aerodynamic
diameter
less
than
2.5
μm),
PM10
10
μm)
using
situ
satellite
measurements
1
March
31
June
2022
(pre-,
full-,
partial-,
post-lockdown
periods).
results
show
that
benefit
significantly
decreased
ground-level
PM2.5,
PM10,
NO2
was
offset
amplified
O3
pollution,
therefore
leading
increased
AQI.
According
backward
trajectory
analyses
multiple
linear
regression
(MLR)
model,
emissions
dominated
observed
changes
pollutants
full-lockdown
period
relative
previous
years
(2019–2021),
whereas
long-range
transport
local
meteorological
parameters
(temperature,
pressure,
wind
speed,
humidity,
precipitation)
influenced
little.
We
further
identified
chemical
mechanism
caused
increase
concentration.
pollution
oxides
(NOx)
under
VOC-limited
regime
high
background
concentrations
owing
seasonal
variations.
In
addition,
found
downtown
area,
more
sensitively
responded
lockdown
measures
they
suburbs.
These
findings
provide
new
insights
into
impact
emission
control
restrictions
on
implications
for
future.
Natural Hazards Research,
Год журнала:
2024,
Номер
4(3), С. 401 - 412
Опубликована: Сен. 1, 2024
The
country
wide
lockdown
implemented
during
27th
April
to
14th
June
2021
in
order
prevent
the
spread
of
COVID-19
second
wave
India.
Effect
restricted
resulted
improved
air
quality.
This
study
focuses
on
analyzing
spatio-temporal
distribution
analysis
major
pollutant
concentration
over
Bangalore
city
inverse
distance
weighting
(IDW)
method
is
for
spatial
quantify
concentrations
at
each
location
Urban
Bangalore.
research
considers
distinct
periods
pre-lockdown
and
pandemic
investigate
impact
reduced
human
activities
quality
city.
mainly
utilizes
pollution
data
collected
from
Central
Pollution
Control
Board
(CPCB)
monitoring
stations
across
Bangalore,
including
measurements
pollutants
such
as
PM2.5,
PM10,
O3,
NO2,
SO2,
CO.
IDW
create
high-resolution
maps
both
periods.
provides
valuable
insights
into
variations
levels
though
out
comparative
reveals
significant
changes
between
two
periods;
similarly,
temporal
weekly
average
also
witnessed
negative
anomalies
weeks.
results
indicate
substantial
reductions
lockdown,
attributed
decreased
vehicular
emissions,
industrial
activities,
construction
operations.
period
serves
a
baseline
assessing
improvements
lockdown.
modeling
approach
enhances
our
understanding
patterns
metropolitan
findings
underscore
potential
benefits
implementing
sustainable
strategies
maintain
even
after
subsides.
Atmospheric and Oceanic Science Letters,
Год журнала:
2021,
Номер
14(4), С. 100060 - 100060
Опубликована: Апрель 30, 2021
The
COVID-19
lockdowns
led
to
abrupt
reductions
in
human-related
emissions
worldwide
and
had
an
unintended
impact
on
air
quality
improvement.
However,
quantifying
this
is
difficult
as
meteorological
conditions
may
mask
the
real
effect
of
changes
observed
concentrations
pollutants.
Based
data
at
35
sites
Beijing
from
2015
2020,
a
machine
learning
technique
was
applied
decouple
impacts
meteorology
results
showed
that
("deweathered")
pollutants
(expect
for
O3)
dropped
significantly
due
lockdown
measures.
Compared
with
scenario
without
(predicted
concentrations),
values
PM2.5,
PM10,
SO2,
NO2,
CO
during
decreased
by
39.4%,
50.1%,
51.8%,
43.1%,
35.1%,
respectively.
In
addition,
significant
decline
NO2
found
background
(51%
37.8%)
rather
than
traffic
(37.1%
35.5%),
which
different
common
belief.
While
primary
reduced
period,
episodic
haze
events
still
occurred
unfavorable
conditions.
Thus,
developing
optimized
strategy
tackle
pollution
essential
future.
摘要
基于2015–2020年北京35个环境空气站和20个气象站观测资料,
应用机器学习方法
(随机森林算法)
分离了气象条件和源排放对大气污染物浓度的影响.
结果发现,
为应对疫情采取的隔离措施使北京2020年春节期间大气污染物浓度降低了35.1%–51.8%;
其中,
背景站氮氧化物和一氧化碳浓度的降幅最大,
超过了以往报道较多的交通站点.
同时,
2020年春节期间的气象条件不利于污染物扩散,
导致多次霾污染事件发生.为进一步改善北京空气质量,
未来需要优化减排策略.