Reducing Aerosol Forcing Uncertainty by Combining Models With Satellite and Within‐The‐Atmosphere Observations: A Three‐Way Street
Reviews of Geophysics,
Год журнала:
2023,
Номер
61(2)
Опубликована: Май 4, 2023
Abstract
Aerosol
forcing
uncertainty
represents
the
largest
climate
overall.
Its
magnitude
has
remained
virtually
undiminished
over
past
20
years
despite
considerable
advances
in
understanding
most
of
key
contributing
elements.
Recent
work
produced
modest
increases
only
confidence
estimate
itself.
This
review
summarizes
contributions
toward
reducing
aerosol
made
by
satellite
observations,
measurements
taken
within
atmosphere,
as
well
modeling
and
data
assimilation.
We
adopt
a
more
measurement‐oriented
perspective
than
reviews
subject
assessing
strengths
limitations
each;
gaps
possible
ways
to
fill
them
are
considered.
Currently
planned
programs
supporting
advanced,
global‐scale
surface‐based
aerosol,
cloud,
precursor
gas
modeling,
intensive
field
campaigns
aimed
at
characterizing
underlying
physical
chemical
processes
involved,
all
essential.
But
addition,
new
efforts
needed:
(a)
obtain
systematic
aircraft
situ
capturing
multi‐variate
probability
distribution
functions
particle
optical,
microphysical,
properties
(and
associated
estimates),
co‐variability
with
meteorology,
for
major
airmass
types;
(b)
conceive,
develop,
implement
suborbital
(aircraft
plus
surface‐based)
program
systematically
quantifying
cloud‐scale
microphysics,
cloud
optical
properties,
cloud‐related
vertical
velocities
aerosol‐cloud
interactions;
(c)
focus
much
research
on
integrating
unique
measurements,
reduce
persistent
forcing.
Язык: Английский
Lightning declines over shipping lanes following regulation of fuel sulfur emissions
Atmospheric chemistry and physics,
Год журнала:
2025,
Номер
25(5), С. 2937 - 2946
Опубликована: Март 11, 2025
Abstract.
Aerosol
interactions
with
clouds
represent
a
significant
uncertainty
in
our
understanding
of
the
Earth
system.
Deep
convective
may
respond
to
aerosol
perturbations
several
ways
that
have
proven
difficult
elucidate
observations.
Here,
we
leverage
two
busiest
maritime
shipping
lanes
world,
which
emit
particles
and
their
precursors
into
an
otherwise
relatively
clean
tropical
marine
boundary
layer,
make
headway
on
influence
deep
clouds.
The
recent
7-fold
change
allowable
fuel
sulfur
by
International
Maritime
Organization
allows
us
test
sensitivity
lightning
changes
ship
plume
number-size
distributions.
We
find
that,
across
range
atmospheric
thermodynamic
conditions,
previously
documented
enhancement
over
has
fallen
40
%.
is
therefore
at
least
partially
aerosol-mediated,
conclusion
supported
observations
droplet
number
cloud
base,
show
similar
decline
lane.
These
results
fundamental
implications
for
aerosol–cloud
interactions,
suggesting
are
impacted
distribution
remote
environment.
Язык: Английский
Aerosol trends dominate over global warming-induced cloud feedback in driving recent changes in marine low clouds
Research Square (Research Square),
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 13, 2025
Abstract
Over
the
past
two
decades,
anthropogenic
emission
reductions
and
global
warming
have
impacted
marine
low
clouds
through
aerosol-cloud
interactions
(ACI)
cloud
feedback,
yet
their
quantitative
contributions
remain
unclear.
This
study
employs
a
deep
learning
model
(CNN
Met−Nd)
Community
Earth
System
Model
version
2
(CESM2)
to
disentangle
these
effects.
CNN
Met−Nd
reveals
that
aerosol-driven
changes
in
droplet
number
concentration
dominate
near-global
shortwave
radiative
effect
(ΔCRE),
contributing
0.42
±
0.08
Wm⁻²
per
20
years,
compared
0.05
0.37
from
feedback.
CESM2
effectively
reproduces
predominant
influence
of
aerosol
on
ΔCRE
by
CNN
Met−Nd,
lending
us
confidence
for
stronger
estimate
effective
forcing
due
ACI
(ERF
aci)
-1.29
since
preindustrial
era.
These
findings
highlight
critical
role
shaping
trends
its
broader
climate
implications,
especially
under
ongoing
reduction
efforts.
Язык: Английский
Improving prediction of marine low clouds using cloud droplet number concentration in a convolutional neural network
Authorea (Authorea),
Год журнала:
2024,
Номер
unknown
Опубликована: Июль 17, 2024
Marine
low
clouds
significantly
cool
the
climate,
but
predicting
these
remains
challenging:
response
of
to
various
factors
is
highly
non-linear.
Previous
studies
usually
overlook
effects
cloud
droplet
number
concentration
(Nd)
and
non-local
information
target
grids.
To
address
challenges,
we
introduce
a
convolutional
neural
network
model
(CNNMet-Nd)
that
uses
both
local
includes
Nd
as
cloud-controlling
factor
enhance
predictive
ability
cover,
albedo,
radiative
(CRE)
for
global
marine
clouds.
CNNMet-Nd
demonstrates
superior
performance,
explaining
over
70%
variance
in
three
variables
instantaneous
scenes
1°×1°,
notable
improvement
past
efforts.
also
accurately
replicates
geographical
patterns
trends
from
2003
2022.
In
contrast,
similar
without
input
(CNNMet)
fails
predict
mean
properties
effectively,
underscoring
critical
role
Nd.
Further
comparisons
with
an
artificial
(ANNMet-Nd)
model,
which
same
inputs
considering
spatial
dependence,
show
CNNMet-Nd's
performance
R2
values
CRE
being
0.16,
0.11,
0.18
higher,
respectively.
This
highlights
importance
incorporating
into
predictions
climate
parameterizations.
Язык: Английский
Aggressive Aerosol Mitigation Policies Reduce Chances of Keeping Global Warming to Below 2C
Earth s Future,
Год журнала:
2024,
Номер
12(7)
Опубликована: Июль 1, 2024
Abstract
Aerosol
increases
over
the
20th
century
delayed
rate
at
which
Earth
warmed
as
a
result
of
in
greenhouse
gases
(GHGs).
Aggressive
aerosol
mitigation
policies
arrested
radiative
forcing
from
∼1980
to
∼2010.
Recent
evidence
supports
decreases
magnitude
since
then.
Using
approximate
partial
perturbation
(APRP)
method,
future
shortwave
effective
changes
are
isolated
other
an
18‐member
ensemble
ScenarioMIP
projections
phase
6
Coupled
Model
Intercomparison
Project
(CMIP6).
APRP‐derived
near‐term
(2020–2050)
trends
correlated
with
published
model
emulation
values
but
30%–50%
weaker.
Differences
likely
explained
by
location
shifts
aerosol‐impacting
emissions
and
their
resultant
influences
on
susceptible
clouds.
Despite
weaker
changes,
implementation
aggressive
cleanup
will
have
major
impact
global
warming
rates
2020–2050.
forcings
used
together
impulse
response
estimate
temperature
trends.
Strong
GHGs,
SSP1‐2.6,
prevents
exceeding
2C
preindustrial
strong
this
scenario
probability
2050
near
zero
without
6%
cleanup.
When
same
is
applied
more
GHG
(i.e.,
SSP2‐4.5),
than
doubles
reaching
30%
80%.
It
thus
critical
quantify
simulate
impacts
next
few
decades.
Язык: Английский
Aggressive aerosol mitigation policies reduce chances of keeping global warming to below 2C
Authorea (Authorea),
Год журнала:
2023,
Номер
unknown
Опубликована: Ноя. 9, 2023
Aerosol
increases
over
the
20th
century
delayed
rate
at
which
Earth
warmed
as
a
result
of
in
greenhouse
gases
(GHGs).
Aggressive
aerosol
mitigation
policies
arrested
radiative
forcing
from
~1980
to
~2010.
Recent
evidence
supports
decreases
magnitude
since
then.
Using
approximate
partial
perturbation
(APRP)
method,
future
shortwave
effective
changes
are
isolated
other
an
18-member
ensemble
ScenarioMIP
projections
phase
6
Coupled
Model
Intercomparison
Project
(CMIP6).
APRP-derived
near-term
(2020-2050)
trends
correlated
with
published
model
emulation
values
but
30-50%
weaker.
Differences
likely
explained
by
location
shifts
aerosol-impacting
emissions
and
their
resultant
influences
on
susceptible
clouds.
Despite
weaker
changes,
implementation
aggressive
cleanup
will
have
major
impact
global
warming
rates
2020-2050.
forcings
used
together
impulse
response
estimate
temperature
trends.
Strong
GHGs,
SSP1-2.6,
prevents
exceeding
2C
preindustrial
strong
this
scenario
probability
2050
near
zero
without
6%
cleanup.
When
same
is
applied
more
GHG
(i.e.,
SSP2-4.5),
than
doubles
reaching
30%
80%.
It
thus
critical
quantify
simulate
impacts
next
few
decades.
Язык: Английский
Improving Prediction of Marine Low Clouds Using Cloud Droplet Number Concentration in a Convolutional Neural Network
Journal of Geophysical Research Machine Learning and Computation,
Год журнала:
2024,
Номер
1(4)
Опубликована: Ноя. 30, 2024
Abstract
Marine
low
clouds
play
a
crucial
role
in
cooling
the
climate,
but
accurately
predicting
them
remains
challenging
due
to
their
highly
non‐linear
response
various
factors.
Previous
studies
usually
overlook
effects
of
cloud
droplet
number
concentration
(N
d
)
and
non‐local
information
target
grids.
To
address
these
challenges,
we
introduce
convolutional
neural
network
model
(CNN
Met‐Nd
that
uses
both
local
includes
N
as
cloud‐controlling
factor
enhance
predictive
ability
daily
cover,
albedo,
radiative
(CRE)
for
global
marine
clouds.
CNN
demonstrates
superior
performance,
explaining
over
70%
variance
three
variables
scenes
1°
×
1°,
notable
improvement
past
efforts.
also
replicates
geographical
patterns
trends
from
2003
2022.
In
contrast,
similar
without
Met
struggles
predict
long‐term
properties
effectively.
Permutation
importance
analysis
further
highlights
critical
Met‐N
's
success.
Further
comparisons
with
an
artificial
(ANN
model,
which
same
inputs
considering
spatial
dependence,
show
performance
R
2
values
CRE
being
0.16,
0.12,
0.18
higher,
respectively.
This
incorporating
information,
at
least
on
scale,
into
predictions
climate
parameterizations.
Язык: Английский