It
is
now
well
established
that
the
Arctic
warming
at
a
faster
rate
than
global
average.
This
warming,
which
has
been
accompanied
by
dramatic
decline
in
sea
ice,
linked
to
cooling
over
Eurasian
subcontinent
recent
decades,
most
dramatically
during
period
1998–2012.
counterintuitive
impact
under
given
land
regions
should
warm
more
ocean
(and
average).
Some
studies
have
proposed
causal
teleconnection
from
ice
retreat
wintertime
cooling;
other
argue
mainly
driven
internal
variability
and
relationship
coincidental.
Overall,
there
an
impression
of
strong
disagreement
between
those
holding
“ice-driven”
versus
“internal
variability”
viewpoints.
Here,
we
offer
alternative
framing
showing
views
can
be
compatible.
Key
this
viewing
through
lens
dynamics
(linked
primarily
with
small
contribution
ice;
cools
Eurasia)
thermodynamics
retreat;
warms
Eurasia).
approach,
combined
recognition
uncertainty
hypothesized
mechanisms
themselves,
allow
both
viewpoints
others)
co-exist
contribute
our
understanding
cooling.
A
simple
autoregressive
model
shows
magnitude
consistent
variability,
some
periods
being
susceptible
others.
Rather
posit
“yes-or-no”
cooling,
constructive
way
forward
consider
whether
trend
was
likely
observed
loss,
as
sources
low-frequency
variability.
Taken
are
factors
affect
likelihood
regional
presence
ongoing
warming.
Journal of Geophysical Research Atmospheres,
Год журнала:
2023,
Номер
128(6)
Опубликована: Март 8, 2023
Abstract
Ural
blocking
(UB)
is
a
prominent
mode
of
variability
the
Northern
Hemisphere
atmospheric
circulation,
particularly
in
fall.
It
can
persist
for
several
days
and
exert
lagged
influence
on
wintertime
NH
providing
predictability
at
subseasonal
time
scale.
Using
two
models,
we
explore
how
early
winter
circulation
responds
to
2‐week
persistent
UB
anomaly
imposed
November.
Experiments
are
carried
out
with
different
configurations
Barents‐Kara
(BK)
sea‐ice
concentration
examine
whether
it
plays
role
impacts
variability.
In
both
followed
by
weakening
stratospheric
polar
vortex
negative
phase
North
Atlantic
Oscillation
(NAO),
which
lasts
up
2
months
after
forcing
released.
Interestingly,
response
more
under
low
BK
conditions,
that
is,
sea
ice
modulates
UB.
Additional
experiments
prescribed
anomalies
alone
suggest
exerts
limited
The
involves
persists
longer
ice,
explains
configuration.
Our
study
highlights
November
robust
precursor
NAO/polar
stratosphere
anomalies,
this
may
be
relevant
context
declining
Arctic
extent.
Provided
climate
models
accurately
capture
teleconnection,
has
potential
improve
predictions
climate.
Weather and Climate Dynamics,
Год журнала:
2023,
Номер
4(1), С. 95 - 114
Опубликована: Янв. 18, 2023
Abstract.
It
is
now
well
established
that
the
Arctic
warming
at
a
faster
rate
than
global
average.
This
warming,
which
has
been
accompanied
by
dramatic
decline
in
sea
ice,
linked
to
cooling
over
Eurasian
subcontinent
recent
decades,
most
dramatically
during
period
1998–2012.
counter-intuitive
impact
under
given
land
regions
should
warm
more
ocean
(and
average).
Some
studies
have
proposed
causal
teleconnection
from
sea-ice
retreat
wintertime
cooling;
other
argue
mainly
driven
internal
variability.
Overall,
there
an
impression
of
strong
disagreement
between
those
holding
“ice-driven”
versus
“internal
variability”
viewpoints.
Here,
we
offer
alternative
framing
showing
ice
and
variability
views
can
be
compatible.
Key
this
viewing
through
lens
dynamics
(linked
primarily
with
some
potential
contribution
ice;
cools
Eurasia)
thermodynamics
retreat;
warms
Eurasia).
approach,
combined
recognition
uncertainty
hypothesized
mechanisms
themselves,
allows
both
viewpoints
others)
co-exist
contribute
our
understanding
cooling.
A
simple
autoregressive
model
shows
magnitude
consistent
variability,
periods
exhibiting
stronger
others,
either
chance
or
forced
changes.
Rather
posit
“yes-or-no”
relationship
cooling,
constructive
way
forward
consider
whether
trend
was
likely
observed
loss,
as
sources
low-frequency
Taken
are
factors
affect
likelihood
regional
presence
ongoing
warming.
Weather and Climate Dynamics,
Год журнала:
2022,
Номер
3(3), С. 951 - 975
Опубликована: Авг. 17, 2022
Abstract.
The
extent
to
which
interannual
variability
in
Arctic
sea
ice
influences
the
mid-latitude
circulation
has
been
extensively
debated.
While
observational
data
support
existence
of
a
teleconnection
between
November
Barents–Kara
region
and
subsequent
winter
North
Atlantic
Oscillation,
climate
models
do
not
consistently
reproduce
such
link,
with
only
very
weak
inter-model
consensus.
We
show,
using
EC-Earth3
model,
that
while
an
ensemble
coupled
simulations
shows
no
evidence
teleconnection,
inclusion
stochastic
parameterizations
ocean
component
results
emergence
robust
comparable
magnitude
observed.
exact
mechanisms
causing
this
remain
unclear,
we
argue
it
can
be
accounted
for
by
improved
ice–ocean–atmosphere
coupling
due
perturbations,
aim
represent
effect
unresolved
variability.
In
particular,
consensus
may
large
model
biases
surface
coupling,
being
one
possible
remedy.
Communications Earth & Environment,
Год журнала:
2024,
Номер
5(1)
Опубликована: Авг. 2, 2024
The
Arctic
has
experienced
a
rapid
sea
ice
loss
in
the
Barents
and
Kara
Seas
winter
over
satellite
era.
Such
been
modulated
by
anthropogenic
forcing
internal
variability,
but
precise
estimate
of
their
relative
contribution
remains
unclear.
Here,
using
large
ensemble
simulations
machine-learning
techniques,
we
successfully
reproduce
wintertime
Barents-Kara
trends
as
joint
impact
variability
components.
Over
whole
period,
contributes
about
70%
to
loss,
with
contributing
remainder.
However,
is
more
important
explaining
varying
shorter
periods
(~20
years),
including
accelerated
up
2017,
consistent
an
extreme,
unforced
atmospheric
circulation
dipole
trend
Euro-Atlantic
sector.
Overall,
this
study
highlights
that
plays
role
shaping
recent
than
previously
thought,
implications
for
projections
use
machine
learning
methods
future
attribution
studies.
Internal
period
though
primary
influence,
according
analyzed
machine-learning.
Journal of Geophysical Research Atmospheres,
Год журнала:
2023,
Номер
128(17)
Опубликована: Сен. 2, 2023
Abstract
To
analyze
links
among
key
processes
that
contribute
to
Arctic‐midlatitude
teleconnections
we
apply
causal
discovery
based
on
graphical
models
known
as
graphs.
First,
calculate
the
dependencies
from
observations
during
1980–2021.
Observations
show
several
robust
connections
early
late
winter,
such
atmospheric
blocking
within
central
Asia
via
Ural
and
Siberian
High,
North
Atlantic
Oscillation
phase
polar
vortex
(PV).
The
PV
is
affected
by
poleward
eddy
heat
flux
at
100
hPa,
which
also
directly
connected
with
Aleutian
Low.
We
then
evaluate
climate
participating
in
Coupled
Model
Intercomparison
Project
Phase
6
(CMIP6)
comparing
their
graphs
those
derived
observations.
Compared
observations,
CMIP6
historical
future
simulations
do
not
robustly
capture
arising
Arctic
sea
ice
variability.
This
highlights
role
of
internal
variability
modulating
teleconnections.
However,
find
distinct
patterns
are
simulated
most
analyzed
models.
For
example,
both
model
observed
Asia.
But
contrary
a
link
between
temperature
cover
over
Barents
Kara
seas.
analysis
changes
reveals
connection
Low
hPa
expected
become
more
toward
end
21st
century
than
past.
Abstract.
It
is
now
well
established
that
the
Arctic
warming
at
a
faster
rate
than
global
average.
This
warming,
which
has
been
accompanied
by
dramatic
decline
in
sea
ice,
linked
to
cooling
over
Eurasian
subcontinent
recent
decades,
most
dramatically
during
period
1998–2012.
counterintuitive
impact
under
given
land
regions
should
warm
more
ocean
(and
average).
Some
studies
have
proposed
causal
teleconnection
from
ice
retreat
wintertime
cooling;
other
argue
mainly
driven
internal
variability
and
relationship
coincidental.
Overall,
there
an
impression
of
strong
disagreement
between
those
holding
“ice-driven”
versus
“internal
variability”
viewpoints.
Here,
we
offer
alternative
framing
showing
views
can
be
compatible.
Key
this
viewing
through
lens
dynamics
(linked
primarily
with
small
contribution
ice;
cools
Eurasia)
thermodynamics
retreat;
warms
Eurasia).
approach,
combined
recognition
uncertainty
hypothesized
mechanisms
themselves,
allow
both
viewpoints
others)
co-exist
contribute
our
understanding
cooling.
A
simple
autoregressive
model
shows
magnitude
consistent
variability,
some
periods
being
susceptible
others.
Rather
posit
“yes-or-no”
cooling,
constructive
way
forward
consider
whether
trend
was
likely
observed
loss,
as
sources
low-frequency
variability.
Taken
are
factors
affect
likelihood
regional
presence
ongoing
warming.
Arctic and Antarctic Research,
Год журнала:
2022,
Номер
68(3), С. 234 - 247
Опубликована: Сен. 27, 2022
The
ongoing
decrease
in
the
ice
coveren
is
one
of
main
consequences
global
climate
change.
Barents
Sea,
as
part
North
European
basin,
an
area
that
first
to
react
these
changes.
According
AARI
database,
before
start
current
century
extent
winter
season
varied
from
600·10
3
km
2
900·10
different
years,
while
over
past
20
years
lower
border
has
dropped
350·10
.
At
same
time,
summer
decreased
more
than
times.
aim
article
study
statistical
structure
longterm
variability
on
basis
latest
data,
order
identify
patterns
change
characteristic
individual
areas
Sea
decades.
research
methods
include
basic
statistics,
linear
trend,
stationary
assessment,
autocorrelation
and
correlation
coefficient.
work
contains
numerical
estimates
trend
component
for
all
parts
water
area.
maximum
contribution
due
northeastern
region
comprises
63
%.
seasonal
fluctuations
are
southeastern
region,
with
almost
complete
freezing
(up
99
%,
northeast)
clearing
absence
old
ice.
least
connection
other
(R
less
0.25)
its
characteristics
depends
a
greater
not
only
circulation
cold
Arctic
waters
entry
warm
Atlantic
water,
but
also
river
runoff.
north-eastern
characterized
by
capacity
retaining
“memory”
previous
state
5
which
indicates
highest
inertia
factors
making
extent.
speed
reducing
because
melting
estimated
at
1.76·10
/month,
rate
increase
result
growth
1.26·10
/month.
Accordingly,
melts
faster
it
time
grow,
leads
Geophysical Research Letters,
Год журнала:
2023,
Номер
50(8)
Опубликована: Апрель 23, 2023
Abstract
The
causality
of
the
link
between
Autumn
Barents‐Kara
(BK)
sea
ice
and
winter
North
Atlantic
Oscillation
(NAO)
is
uncertain,
given
teleconnections
stemming
from
tropics
may
influence
both
extra‐tropics
Arctic.
We
explore
relationship
tropical
rainfall
BK
in
autumn,
by
nudging
to
follow
observed
variability
otherwise
free
running
ensemble
simulations.
Tropical
forcing
alone
can
skillfully
reproduce
a
significant
fraction
interannual
NAO
late
autumn.
also
show
that
strongly
related
simulated
ice.
As
result,
we
are
able
some
autumn
However,
only
during
strong
1997
El
Niño
clear
influences
at
high
latitudes
found.
Large
ensembles
required
detect
forced
models
latitudes.
Abstract.
A
seminal
study
by
Hoskins
and
Karoly
(1981)
explored
the
atmospheric
circulation
response
to
tropospheric
heating
perturbations
at
low
mid
latitudes.
Here
we
revisit
extend
their
investigating
temperature
low,
high
latitude
surface
using
an
idealised
moist,
gray
radiation
model.
Our
results
corroborate
previous
findings
showing
that
latitudes
are
balanced
different
mean
responses
-
upward
motion
horizontal
advection,
respectively.
Transient
eddy
heat
flux
divergence
plays
increasingly
important
role
with
latitude,
becoming
main
However,
this
mechanism
is
less
efficient
balancing
than
leading
greater
reliance
on
additional
contribution
from
radiative
cooling.
These
dynamical
adjustments
promote
stronger
lower
warming
for
compared
latitudes,
suggesting
a
which
sea
ice
loss
promotes
polar-amplified
signal
of
climate
change.