Abstract.
We
review
how
the
international
modelling
community,
encompassing
Integrated
Assessment
models,
global
and
regional
Earth
system
climate
impact
have
worked
together
over
past
few
decades,
to
advance
understanding
of
change
its
impacts
on
society
environment,
support
policy.
then
recommend
a
number
priority
research
areas
for
coming
~6
years
(i.e.
until
~2030),
timescale
that
matches
newly
starting
activities
encompasses
IPCC
7th
Report
(AR7)
2nd
UNFCCC
Global
Stocktake.
Progress
in
these
will
significantly
our
increase
quality
utility
science
emphasize
need
continued
improvement
of,
ability
simulate,
coupled
change.
There
is
an
urgent
investigate
plausible
pathways
emission
scenarios
realize
Paris
Climate
Targets,
including
overshoot
1.5
°C
2
targets,
before
later
returning
them.
System
models
(ESMs)
be
capable
thoroughly
assessing
such
warming
overshoots,
particular,
efficacy
negative
CO2
actions
reducing
atmospheric
driving
cooling.
An
improved
assessment
long-term
consequences
stabilizing
at
or
above
pre-industrial
temperatures
also
required.
ESMs
run
CO2-emission
mode,
more
fully
represent
-
carbon
cycle
feedbacks.
Regional
downscaling
should
use
forcing
data
from
simulations,
so
projections
are
as
realistic
possible.
accurate
simulation
observed
record
remains
key
requirement
does
metrics,
Effective
Sensitivity.
For
adaptation,
guidance
potential
changes
extremes
modes
variability
develop
in,
demand.
Such
improvements
most
likely
realized
through
combination
increased
model
resolution
parameterizations.
propose
deeper
collaboration
across
efforts
targeting
process
realism
coupling,
enhanced
resolution,
parameterization
improvement,
data-driven
Machine
Learning
methods.
With
respect
sampling
future
uncertainty,
between
approaches
large
ensembles
those
focussed
statistical
emulation
attention
paid
High
Impact
Low
Likelihood
(HILL)
outcomes.
In
risk
exceeding
critical
tipping
points
during
overshoot.
comprehensive
change,
arising
directly
specific
mitigation
actions,
it
important
detailed,
disaggregated
information
Models
(IAMs)
used
generate
available
models.
Conversely,
methods
developed
incorporate
societal
responses
into
scenario
development.
Finally,
new
data,
scientific
advances,
proposed
this
article
not
possible
without
development
maintenance
robust,
globally
connected
infrastructure
ecosystem.
This
must
easily
accessible
useable
all
communities
world,
allowing
community
engaged
developing
delivering
knowledge
Earth s Future,
Journal Year:
2025,
Volume and Issue:
13(5)
Published: May 1, 2025
Abstract
This
study
addresses
computational
challenges
in
high‐resolution,
large‐domain,
process‐based
flood
quantile
estimation,
focusing
on
Japan's
future
risks
at
150
m
resolution.
Using
the
Aggregating
Grid
Event
(AGE)
method,
Rainfall‐Runoff‐Inundation
(RRI)
model,
and
Peaks‐Over‐Threshold
(POT)
approach,
it
incorporates
2,160‐year
precipitation
data
from
a
5‐km
dynamically
downscaled
ensemble
(d4PDF
DDSJP)
across
three
climate
stages
(historical,
+2°C,
+4°C).
The
AGE
method
identified
critical
events
for
estimations
POT
was
employed
to
estimate
100‐year
discharge
(Q100)
over
2.2
million
river
grid
cells.
Key
findings
include:
(a)
Nationwide,
is
projected
increase
1.16
times
(+2°C)
1.37
(+4°C),
with
equivalent
return
periods
reduced
45
years
23
(+4°C).
Northern
regions
(Hokkaido
Tohoku)
are
particularly
climate‐sensitive,
exceeding
national
averages
Q100
increases.
(b)
Small
basins
transition
zones
plains
mountains
exhibit
higher
ratios,
necessitating
targeted
prevention
measures.
(c)
Flash
expected
rise,
most
seeing
flashiness
increases
of
10%
20%
Southern
Japan
faces
further
flash
intensification,
while
under
+4°C
stage
anticipates
emerging
related
floods.
underscores
urgency
adaptive
management
strategies
mitigate
increasing
risks,
offering
foundation
informed
policymaking
public‐engaged
mitigation.
Simulation
opens
pathways
research
cascading
disaster
scenarios
+2°C
climates.
Abstract.
We
review
how
the
international
modelling
community,
encompassing
Integrated
Assessment
models,
global
and
regional
Earth
system
climate
impact
have
worked
together
over
past
few
decades,
to
advance
understanding
of
change
its
impacts
on
society
environment,
support
policy.
then
recommend
a
number
priority
research
areas
for
coming
~6
years
(i.e.
until
~2030),
timescale
that
matches
newly
starting
activities
encompasses
IPCC
7th
Report
(AR7)
2nd
UNFCCC
Global
Stocktake.
Progress
in
these
will
significantly
our
increase
quality
utility
science
emphasize
need
continued
improvement
of,
ability
simulate,
coupled
change.
There
is
an
urgent
investigate
plausible
pathways
emission
scenarios
realize
Paris
Climate
Targets,
including
overshoot
1.5
°C
2
targets,
before
later
returning
them.
System
models
(ESMs)
be
capable
thoroughly
assessing
such
warming
overshoots,
particular,
efficacy
negative
CO2
actions
reducing
atmospheric
driving
cooling.
An
improved
assessment
long-term
consequences
stabilizing
at
or
above
pre-industrial
temperatures
also
required.
ESMs
run
CO2-emission
mode,
more
fully
represent
-
carbon
cycle
feedbacks.
Regional
downscaling
should
use
forcing
data
from
simulations,
so
projections
are
as
realistic
possible.
accurate
simulation
observed
record
remains
key
requirement
does
metrics,
Effective
Sensitivity.
For
adaptation,
guidance
potential
changes
extremes
modes
variability
develop
in,
demand.
Such
improvements
most
likely
realized
through
combination
increased
model
resolution
parameterizations.
propose
deeper
collaboration
across
efforts
targeting
process
realism
coupling,
enhanced
resolution,
parameterization
improvement,
data-driven
Machine
Learning
methods.
With
respect
sampling
future
uncertainty,
between
approaches
large
ensembles
those
focussed
statistical
emulation
attention
paid
High
Impact
Low
Likelihood
(HILL)
outcomes.
In
risk
exceeding
critical
tipping
points
during
overshoot.
comprehensive
change,
arising
directly
specific
mitigation
actions,
it
important
detailed,
disaggregated
information
Models
(IAMs)
used
generate
available
models.
Conversely,
methods
developed
incorporate
societal
responses
into
scenario
development.
Finally,
new
data,
scientific
advances,
proposed
this
article
not
possible
without
development
maintenance
robust,
globally
connected
infrastructure
ecosystem.
This
must
easily
accessible
useable
all
communities
world,
allowing
community
engaged
developing
delivering
knowledge
