Authorea (Authorea),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Feb. 20, 2023
Trends
in
tropospheric
ozone,
an
important
air
pollutant
and
short-lived
climate
forcer
(SLCF),
are
estimated
using
available
surface
ozonesonde
profile
data
for
1993-2019.
Using
a
coherent
methodology,
observed
trends
compared
to
modeled
(1995-2015)
from
the
Arctic
Monitoring
Assessment
Programme
SLCF
2021
assessment.
Statistically
significant
increases
ozone
at
coastal
sites,
notably
during
winter,
concurrent
decreasing
carbon
monoxide,
generally
captured
by
multi-model
median
(MMM)
trends.
Wintertime
also
free
troposphere
most
but
tend
be
overestimated
MMMs.
Springtime
northern
Alaska
not
simulated
while
negative
springtime
Scandinavia
always
reproduced.
Possible
reasons
changes
model
behavior
discussed,
including
precursor
emissions,
changing
sinks,
variability
large-scale
meteorology.
ATMOSPHERE-OCEAN,
Journal Year:
2024,
Volume and Issue:
unknown, P. 1 - 12
Published: Nov. 14, 2024
In
this
study,
we
performed,
for
the
first
time,
a
detailed
analysis
of
cloudiness
in
Québec
using
station
based
observations
and
evaluated
trustworthiness
various
satellite
reanalysis
cloud
cover
products.
We
found
only
12
stations
with
observational
time
series
long
enough
providing
robust
due
to
issues
related
observing
methods
recording
information
during
1990s.
Our
results
showed
that
can
be
fairly
cloudy
throughout
year
annual
mean
fraction
ranging
between
0.5
0.7
autumn
being
cloudiest
season
at
most
locations.
also
significantly
increasing
trend
winter
over
1982–2012
(∼2–6%
per
decade
depending
on
location).
Among
products
product
(i.e.
AVHRR)
performed
best
representing
observed
including
wintertime
trend.
Two
ERA5
NARR)
well
indicated
by
high
correlations,
relatively
lower
biases
smaller
root
square
errors.
However,
did
not
capture
seasonal
trends.
All
larger
except
JRA-25
product.
During
warmer
months,
however,
largest
followed
MERRA-2
had
correlation
means
highest
errors
all
seasons.
Furthermore,
two
skill
scores,
ERA5,
AVHRR
NARR
better
than
MERRA-2.
Based
these
conclude
useful
resources
(as
proxies)
along
understanding
term
changes
region
potentially
evaluating
regional
climate
model
simulations.
SSRN Electronic Journal,
Journal Year:
2022,
Volume and Issue:
unknown
Published: Jan. 1, 2022
Highlights
•
Present
and
future
global
PM
2.5
O
3
-related
premature
mortality
is
estimated.
The
present
day
estimated
to
be
5.4
million.
Bias
correction
increases
7.7
Emission
reductions
alone
decreases
by
up
57%
in
2050.
Aging
population
a
factor
of
2.
Atmospheric measurement techniques,
Journal Year:
2022,
Volume and Issue:
15(22), P. 6837 - 6863
Published: Nov. 24, 2022
Abstract.
Measurements
of
Pollution
In
The
Troposphere
(MOPITT)
is
an
instrument
on
NASA's
Terra
satellite
that
has
measured
tropospheric
carbon
monoxide
(CO)
from
early
2000
to
the
present
day.
Validation
data
instruments
like
MOPITT
often
conducted
using
ground-based
measurements
ensure
continued
accuracy
space-based
instrument's
and
its
scientific
results.
Previous
validation
studies
generally
found
a
larger
bias
in
poleward
60∘
N.
this
study,
we
use
2006
2019
Bruker
IFS
125HR
Fourier
Transform
Infrared
spectrometer
(FTIR)
located
at
Polar
Environment
Atmospheric
Research
Laboratory
(PEARL)
Eureka,
Nunavut,
Canada,
validate
version
8
(V8)
retrievals.
These
comparisons
utilize
mid-
near-infrared
FTIR
made
as
part
Network
for
Detection
Composition
Change
(NDACC)
Total
Carbon
Column
Observing
(TCCON),
respectively.
All
retrievals
within
radius
110
km
(1∘)
PEARL
Ridge
24
h
time
interval
are
used
study.
retrieval
products
include
those
(NIR)
channel,
thermal
infrared
(TIR)
joint
product
(TIR–NIR)
channels.
Each
channel's
detector
4
pixels.
We
calculated
pixel-to-pixel
biases
each
pixel,
which
were
vary
based
season
surface
type
(land
or
water).
systematic
pixel
1
over
land
than
other
pixels,
can
reach
up
20
ppb.
small-region
approximation
method
find
filtering
criteria.
then
apply
filters
dataset
minimize
number
outliers
dataset.
sensitivity
examined
Canadian
high
Arctic.
follow
methodologies
recommended
by
NDACC
TCCON
comparison
between
total
column
averaging
kernels
weight
take
into
account
different
vertical
sensitivities
measurements.
modified
Taylor
diagram
results
water
with
Our
show
overall
consistency
When
compared
FTIR,
NIR
have
positive
3
%–10
%
depending
pixel.
values
negative
TIR
product,
−5
0
%.
TIR–NIR
differences
−4
7
drift
(in
units
yr−1)
relative
varies
product.
NIR,
drifts
vs.
smaller
NDACC;
however,
scenario
reversed
products.
Overall,
study
aims
provide
detailed
Authorea (Authorea),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Feb. 20, 2023
Trends
in
tropospheric
ozone,
an
important
air
pollutant
and
short-lived
climate
forcer
(SLCF),
are
estimated
using
available
surface
ozonesonde
profile
data
for
1993-2019.
Using
a
coherent
methodology,
observed
trends
compared
to
modeled
(1995-2015)
from
the
Arctic
Monitoring
Assessment
Programme
SLCF
2021
assessment.
Statistically
significant
increases
ozone
at
coastal
sites,
notably
during
winter,
concurrent
decreasing
carbon
monoxide,
generally
captured
by
multi-model
median
(MMM)
trends.
Wintertime
also
free
troposphere
most
but
tend
be
overestimated
MMMs.
Springtime
northern
Alaska
not
simulated
while
negative
springtime
Scandinavia
always
reproduced.
Possible
reasons
changes
model
behavior
discussed,
including
precursor
emissions,
changing
sinks,
variability
large-scale
meteorology.
