Abstract.
Pyrocumulonimbus
clouds
(pyroCbs)
generated
by
intense
wildfires
can
serve
as
a
direct
pathway
for
the
injection
of
aerosols
and
gaseous
pollutants
into
lower
stratosphere,
resulting
in
significant
chemical,
radiative,
dynamical
changes.
Canada
experienced
an
extremely
severe
wildfire
season
2023,
with
total
area
burned
that
substantially
exceeded
those
previous
events
known
to
have
impacted
stratosphere
(such
2020
Australian
fires).
This
also
had
record-high
pyroCb
activity,
which
raises
question
whether
2023
Canadian
event
resulted
stratospheric
perturbations.
Here,
we
investigate
this
anomalous
using
retrievals
from
two
satellite
instruments,
ACE-FTS
(Atmospheric
Chemistry
Experiment
–
Fourier
Transform
Spectrometer)
OMPS
LP
(Ozone
Mapping
Profile
Suite
Limb
Profiler),
determine
vertical
extents
smoke
along
chemical
signatures
biomass
burning.
These
data
show
primarily
reached
upper
troposphere
but
only
nominal
amount
managed
penetrate
tropopause.
Only
one
occultation
captured
elevated
concentrations
burning
products
on
July
30th,
back
forward
trajectories
place
source
fire
Yukon.
However,
aerosol
measurements
indicate
any
made
it
past
tropopause
did
not
last
long
enough
significantly
perturb
composition.
While
work
focuses
given
extensive
area,
pyroCbs
at
other
longitudes
(e.g.
Siberia)
are
compositional
analysis.
results
highlight
despite
formation
many
major
wildfires,
capable
penetrating
rare;
turn
means
even
massive
is
necessarily
indicator
effects.
Reviews of Geophysics,
Год журнала:
2024,
Номер
62(4)
Опубликована: Окт. 21, 2024
Abstract
Age
of
stratospheric
air
is
a
well
established
metric
for
the
transport
circulation.
Rooted
in
robust
theoretical
framework,
this
approach
offers
benefit
being
deducible
from
observations
trace
gases.
Given
potential
climate‐induced
changes,
observational
constraints
on
circulation
are
crucial.
In
past
two
decades,
scientific
progress
has
been
made
three
main
areas:
(a)
Enhanced
process
understanding
and
development
diagnostics
led
to
better
quantification
individual
processes
model
deficits.
(b)
The
global
age
climatology
now
constrained
by
thanks
improved
quality
quantity
data,
including
satellite
through
consistent
calculation
methods.
(c)
It
understood
that
models
predict
decrease
age,
is,
an
accelerating
circulation,
response
forcing
greenhouse
gases
ozone
depleting
substances.
Observational
records
confirm
long‐term
forced
trends
mean
lower
stratosphere.
However,
mid‐stratosphere,
uncertainties
too
large
or
disprove
predictions.
Continuous
monitoring
further
methods
derive
those
tracers
will
be
crucial
constrain
variability
observations.
Future
work
as
important
due
its
enhance
composition
address
climate
biases,
assess
impacts
proposed
geoengineering
Atmospheric measurement techniques,
Год журнала:
2025,
Номер
18(3), С. 569 - 602
Опубликована: Фев. 3, 2025
Abstract.
Launched
aboard
the
Canadian
SCISAT
satellite
in
August
2003,
Measurement
of
Aerosol
Extinction
Stratosphere
and
Troposphere
Retrieved
by
Occultation
(MAESTRO)
instrument
has
been
measuring
solar
absorption
spectra
ultraviolet
(UV)
visible
part
spectrum
for
more
than
20
years.
The
UV-channel
measurements
from
MAESTRO
are
used
to
retrieve
profiles
ozone
short-wavelength
end
Chappuis
band
(UV-ozone)
NO2,
while
made
a
separate
(Vis-ozone)
product.
latest
NO2
profile
products,
version
4.5,
have
released,
they
initially
cover
period
February
2004
December
2023,
although
will
continue
be
updated.
4.5
retrieval
algorithm
represents
an
improvement
previous
versions,
with
changes
including
updated
pressure
temperature
input
information,
improved
high-Sun
reference
calculation,
Rayleigh
scattering
modelling,
change
Twomey–Tikhonov
inversion
Chahine
relaxation
technique.
Due
buildup
unknown
contaminant,
UV-ozone
products
only
viable
up
June
2009
UV-ozone.
This
study
presents
comparisons
coincident
(both
spatially
temporally)
ensemble
11
other
limb-viewing
instruments.
In
stratosphere,
Vis-ozone
product
was
found
possess
small
high
bias,
stratosphere-averaged
relative
differences
between
2.3
%
8.2
%,
good
agreement
comparison
datasets
overall.
A
similar
albeit
slightly
poorer
agreement,
is
average
stratospheric
ranging
2.8
11.9
%.
For
general
range
40
km.
Within
this
range,
low
bias
most
agree
within
27.2
ranges
8.5
43.4
Geophysical Research Letters,
Год журнала:
2025,
Номер
52(9)
Опубликована: Май 10, 2025
Abstract
In
January
2020,
tropopause‐level
ozone
in
the
austral
mid‐latitudes
was
highest
ever
observed
available
Microwave
Limb
Sounder
data
record
since
2004.
Two
extreme
events
preceded
this
anomaly:
Australian
Black
Summer
fires
and
2019
sudden
stratospheric
warming
(SSW),
raising
question
of
how
these
disruptions
influenced
Southern
Hemisphere
ozone.
Here,
we
investigate
dynamical
chemical
contributions
to
anomaly
using
a
chemistry‐climate
model
satellite
observations.
We
find
that
downward
transport
polar
ozone‐enriched
air
due
SSW
later
spread
equatorward.
Such
together
with
photochemical
production
from
emissions
wildfires
(fueled
by
dry
hot
conditions
previously
attributed
SSW)
increased
up
30
ppb,
as
dominant
factor
(around
80%).
While
is
well‐recognized,
our
results
highlight
SSWs
can
greatly
influence
mid‐latitude
through
effects.
Atmospheric chemistry and physics,
Год журнала:
2025,
Номер
25(10), С. 5199 - 5213
Опубликована: Май 21, 2025
Abstract.
According
to
satellite
measurements
from
multiple
instruments,
water
vapour
(H2O)
concentrations,
in
most
regions
of
the
stratosphere,
have
been
increasing
at
a
statistically
significant
rate
∼1
%–5
%
per
decade
since
early
2000s.
Previous
studies
estimated
stratospheric
H2O
trends,
but
none
simultaneously
quantified
contributions
all
main
sources
(temperature
variations
tropical
tropopause
region,
changes
Brewer–Dobson
circulation,
and
methane
(CH4)
concentrations
oxidation)
latitudes.
Atmospheric
Chemistry
Experiment–Fourier
Transform
Spectrometer
(ACE-FTS)
are
used
estimate
altitude-/latitude-dependent
trends
2004–2021
due
these
sources.
Results
indicate
that
rising
temperatures
region
play
role
increases,
accounting
for
%–4
lower
mid-stratosphere
mid-latitudes
below
∼20
km.
By
regressing
ACE-FTS
N2O
it
is
found
that,
mid-stratosphere,
general
circulation
led
both
increases
decreases
on
order
1
%–2
depending
altitude/latitude
region.
Making
use
measured
modelled
CH4
increase
oxidation
calculated
be
above
∼30
km
Northern
Hemisphere
throughout
stratosphere
Southern
Hemisphere.
After
sources,
there
still
mid-latitude
exhibit
residual
decade.
unaccounted-for
could
potentially
explained
by
upper-tropospheric
molecular
hydrogen.
Atmospheric measurement techniques,
Год журнала:
2024,
Номер
17(8), С. 2429 - 2449
Опубликована: Апрель 23, 2024
Abstract.
The
Atmospheric
Chemistry
Experiment
Fourier
Transform
Spectrometer
(ACE-FTS)
is
currently
providing
the
only
measurements
of
vertically
resolved
chlorodifluoromethane
(HCFC-22)
from
space.
This
study
assesses
ACE-FTS
HCFC-22
v5.2
product
in
upper
troposphere
and
lower
stratosphere,
as
well
simulations
a
39-year
specified
dynamics
run
Canadian
Middle
Atmosphere
Model
(CMAM39)
same
region.
In
general,
observations
tend
to
agree
with
subsampled
CMAM39
data
within
±5
%,
except
for
between
∼
15
25
km
extratropical
regions
where
exhibits
negative
bias
5
%–30
%
near
6
tropics
−15
%.
When
comparing
against
correlative
satellite,
aircraft,
balloon
data,
typically
low
on
order
0
%–10
±15
km.
ACE-FTS,
CMAM39,
surface
flask
NOAA
Global
Monitoring
Laboratory's
air-sampling
network
all
exhibit
consistent
tropospheric
trends
ranging
6.8
7.8
ppt
yr−1
(within
95
confidence)
2004–2012
3.1
4.7
2012–2018.
Interhemispheric
differences
(IHDs)
were
also
derived
using
NOAA,
three
yielded
correlated
(r≥0.42)
IHD
time
series,
results
indicating
that
values
decreased
at
rate
2.2
±
1.1
per
decade
2004
2018.
Journal of Quantitative Spectroscopy and Radiative Transfer,
Год журнала:
2024,
Номер
325, С. 109088 - 109088
Опубликована: Июнь 18, 2024
The
Atmospheric
Chemistry
Experiment
(ACE)
is
a
satellite
mission
that
has
been
in
orbit
since
2003.
primary
instrument
on
ACE
Fourier
transform
spectrometer
(FTS)
records
infrared
atmospheric
transmittance
spectra
the
limb
geometry
using
Sun
as
light
source.
Version
5
of
ACE-FTS
data
processing
contains
improved
volume
mixing
ratio
(VMR)
profiles
for
46
molecules
and
24
isotopologues,
including
HFC-32
(CH2F2)
HOCl
new
routine
products.
VMR
trends
each
are
reported
regions
interest.
Specifically,
longevity
provided
an
opportunity
to
monitor
effectiveness
Montreal
Protocol
Substances
Deplete
Ozone
Layer.
It
observed
chlorofluorocarbons
(CFCs)
declining,
hydrochlorofluorocarbons
(HCFCs)
no
longer
increasing,
but
hydrofluorocarbons
(HFCs)
still
increasing
rapidly.
Greenhouse
gases
such
carbon
dioxide
also
monitored
comparisons
with
National
Oceanic
Administration
(NOAA)
Advanced
Global
Gases
(AGAGE)
measurements
made.
Journal of Geophysical Research Atmospheres,
Год журнала:
2025,
Номер
130(9)
Опубликована: Май 6, 2025
Abstract
Carbonyl
sulfide
(OCS)
is
an
important
atmospheric
sulfur
species
that
plays
a
dominant
role
in
the
formation
of
(nonvolcanic)
stratospheric
sulfate
aerosol
middle
stratosphere.
Major
uncertainties
surface
sources
and
sinks
inconsistent
model
representation
vertical
transport
limit
understanding
OCS
distribution,
particularly
sparsely
sampled
upper
atmosphere.
During
2022
Asian
Summer
Monsoon
Chemical
CLimate
Impact
Project
(ACCLIP)
campaign,
situ
measurements
Upper
Troposphere
Lower
Stratosphere
(UTLS)
at
eastern
edge
summer
monsoon
anticyclone
(ASM),
showed
significant
enhancements
(>750
ppt)
near
tropopause
from
convectively
influenced
air
parcels.
Here,
we
compare
these
novel
UTLS
with
long‐term
satellite
observations
regional
to
broaden
trends
its
by
ASM.
Trajectory
analysis
identifies
northern
China
as
main
source
region
for
deep
convective
lofting
OCS‐enriched
parcels
demonstrates
ASM
entrainment
UTLS,
allowing
evaluation
global
predictions
OCS's
influence.
The
ACCLIP
data
set
provides
vital
validation
limited
vertically
resolved
anthropogenic
emissions,
which
serves
enhance
our
budget.
