Remote Sensing,
Journal Year:
2024,
Volume and Issue:
16(10), P. 1781 - 1781
Published: May 17, 2024
Using
CloudSat/CALIPSO
satellite
data
and
ERA5
reanalysis
from
2006
to
2010,
the
effects
of
aerosols
on
ice-
mixed-phase,
single-layer,
non-precipitating
clouds
over
Tibetan
Plateau
during
nighttime
in
MAM
(March
May),
JJA
(June
August),
SON
(September
November),
DJF
(December
February)
seasons
were
examined.
The
results
indicated
following:
(1)
macrophysical
microphysical
characteristics
mixed-phase
exhibit
a
nonlinear
trend
with
increasing
aerosol
optical
depth
(AOD).
When
logarithm
AOD
(lnAOD)
was
≤−4.0,
nights,
cloud
thickness
ice
particle
effective
radius
ice-phase
clouds,
water
path
number
concentration
liquid
fraction
all
decreased;
top
height,
droplet
concentration,
decreased.
lnAOD
>−4.0,
base
fraction,
increased;
increased.
(2)
Under
condition
excluding
meteorological
factors,
including
U-component
wind,
V-component
pressure
vertical
velocity,
temperature,
relative
humidity
at
atmospheric
heights
near
average
within
cloud,
as
well
precipitable
vapor,
convective
available
potential
energy,
surface
pressure.
During
nights.
an
increase
may
have
led
decrease
layers,
reduction
values.
In
contrast,
when
contribute
elevated
for
clouds.
changes
various
be
influenced
by
both
factors.
Journal of Geophysical Research Atmospheres,
Journal Year:
2024,
Volume and Issue:
129(13)
Published: July 4, 2024
Abstract
Entrainment
and
detrainment
rates
(
ε
δ
)
constitute
the
most
critical
free
parameters
in
mass
flux
schemes
commonly
employed
for
cumulus
parameterizations.
Recently,
Zhu
et
al.
(2021)
introduced
a
new
approach
that
utilizes
aircraft
observations
to
simultaneously
estimate
clouds,
overcoming
limitation
of
other
observation‐based
approaches
solely
yield
without
offering
insights
into
.
This
study
aims
comprehensively
evaluate
reliability
this
approach.
First,
evaluation
using
an
Explicit
Mixing
Parcel
Model
demonstrates
capability
back‐calculate
predetermined
based
on
physical
properties
before
after
entrainment
mixing.
Second,
large‐eddy
simulations
illustrates
yields
consistent
profiles
compared
traditional
Sensitivity
tests
indicate
weak
sensitivity
estimated
with
entrained
air
source.
A
decrease
proportion
cloudy
assumed
detrained
leads
reduction
,
while
remains
unaffected.
Finally,
appropriate
assumptions
are
discussed.
Estimating
parameterizations
involves
acquiring
ambient
more
than
500
m
away
from
cloud
edge
as
air.
Due
implicit
mean
field
approximations
approach,
determining
optimal
assumption
proves
challenging.
confirms
estimating
providing
confidence
its
application
extensive
observational
data
advancement
parameterization.
Geophysical Research Letters,
Journal Year:
2025,
Volume and Issue:
52(4)
Published: Feb. 12, 2025
Abstract
Parameterizations
of
entrainment
and
detrainment
rates
(
ε
δ
)
are
crucial
for
climate
models.
Although
satellite‐derived
estimates
available
in
the
literature,
there
has
been
a
deficiency
satellite‐based
retrievals
.
To
fill
this
gap,
recently
developed
approach
is
applied
to
satellite
observations.
The
retrieved
validated
against
aircraft
observations
confirming
reliability
Results
show
that
global
exhibit
significant
latitudinal
variations
land‐ocean
contrast,
but
no
interhemispheric
differences.
Near
equator,
relatively
low,
they
increase
with
latitude.
Both
notably
higher
over
oceans
(1.62
1.33
km
−1
,
respectively)
than
land
(0.92
0.64
respectively).
Furthermore,
data
set
can
further
develop
validate
parameterizations
Journal of Advances in Modeling Earth Systems,
Journal Year:
2024,
Volume and Issue:
16(8)
Published: Aug. 1, 2024
Abstract
Different
turbulent
entrainment‐mixing
mechanisms
between
clouds
and
environment
are
essential
to
cloud‐related
processes;
however,
accurate
representation
of
in
weather/climate
models
still
poses
a
challenge.
This
study
exploits
the
use
machine
learning
(ML)
address
this
Four
ML
(Light
Gradient
Boosting
Machine
[LGB],
eXtreme
Boosting,
Random
Forest,
Support
Vector
Regression)
examined
compared.
It
is
found
that
LGB
performs
best,
thus
selected
understand
impact
on
microphysics
using
simulation
data
from
Explicit
Mixing
Parcel
Model.
Compared
with
traditional
parameterizations,
trained
provides
more
microphysical
properties
(number
concentration
cloud
droplet
spectral
dispersion).
The
partial
dependences
predicted
features
exhibit
strong
alignment
physical
expectations,
as
determined
by
interpreting
method,
overcoming
limitations
“black
box”
scheme.
underlying
smaller
number
larger
dispersion
correspond
inhomogeneous
entrainment‐mixing.
Specifically,
after
positively
correlated
adiabatic
liquid
water
content
affected
entrainment‐mixing,
inversely
volume
mean
radius.
Spectral
negatively
dissipation
rate
relative
humidity
entrained
air.
Sensitivity
analysis
further
suggests
mainly
whereas
influenced
both
environmental
variables.
results
indicate
scheme
has
potential
enhance
models.
Geophysical Research Letters,
Journal Year:
2024,
Volume and Issue:
51(19)
Published: Oct. 1, 2024
Abstract
The
influence
of
entrainment,
a
key
process
characterized
by
the
entrainment
rate
in
cumulus
parameterization,
on
aerosol‐cloud
interactions
has
been
widely
recognized.
However,
despite
qualitative
links
established
between
and
aerosol
loading,
quantitative
relationship
based
observational
evidence
remains
elusive.
This
study
utilizes
aircraft
observations
clouds
during
two
field
campaigns
to
determine
loading.
In
both
campaigns,
is
negatively
correlated
with
It
speculated
that
increased
loading
enhances
cloud
edge
droplet
evaporation,
which
leads
buoyancy
vertical
velocity
within
cloud,
thereby
reducing
rate.
Further
analysis
shows
response
perturbations
more
significant
smaller
weak
less
pronounced
under
opposite
conditions.
These
findings
shed
new
light
improving
description
parameterizations.
Geophysical Research Letters,
Journal Year:
2024,
Volume and Issue:
51(9)
Published: May 1, 2024
Abstract
The
physical
behavior
of
a
falling
raindrop
is
governed
by
delicate
fluid
dynamics
and
thermodynamics,
oscillates
with
time.
Despite
this
time‐variant
nature,
past
observational
simulation
studies
have
aimed
to
generalize
parameterizations
for
describing
rain
microphysics
bearing
the
assumption
that
raindrops
fall
at
terminal
speeds
an
equilibrium
shape.
However,
applicability
hypothesis
in
realistic
atmosphere
inherently
turbulent
remains
open
question.
Here,
we
employ
novel
retrieval
techniques
quantify
impact
turbulence
on
using
long‐term
situ
observations
careful
assessment
wind
effect.
We
find
increasingly
deviate
from
state
as
dissipation
rate
increases,
effect
more
pronounced
large
raindrops.
present
turbulence‐invoked
microphysical
which
shed
light
complex
interactions
between
microphysics.
Frontiers in Earth Science,
Journal Year:
2024,
Volume and Issue:
12
Published: May 9, 2024
This
document
summarizes
the
physics
schemes
used
in
two
configurations
of
first
version
operational
Hurricane
Analysis
and
Forecast
System
(HAFSv1)
at
NOAA
NCEP.
The
package
HAFSv1
is
same
as
that
NCEP
global
forecast
system
(GFS)
16
except
for
an
additional
microphysics
scheme
modifications
to
sea
surface
roughness
lengths,
boundary
layer
scheme,
entrainment
rate
deep
convection
scheme.
Those
are
specifically
designed
improving
simulation
tropical
cyclones
(TCs).
mainly
differ
adopted
TC-specific
addition
model
initialization.
Experiments
made
highlight
impacts
different
on
performance.
Challenges
developmental
plans
future
versions
HAFS
discussed.
