5 February 2018
@NIES

Climate Projection and Scenarios

Kiyoshi Takahashi
Center for Social and Environmental Systems Research

National Institute for Environmental Studies

An Integrated Assessment Framework
for Considering Climate Change
Climate System

Climate change
impacts•Temperature rise•Sea level rise
•Precipitation change

Feedbacks

Environmental
impacts

EnhancedgreenhouseeffectAtmospheric
Concentrations•Carbon dioxide•Methane•Nitrous oxide•Aerosols

Human &Natural Systems•Floods and droughts•Biodiversity•Animal and plant health

Anthropogenicemissions

Non-climatechange
stresses

Socio-EconomicDevelopment Paths•Main drivers arepopulation,energy,economic growth,
technology and land use

IPCC,2001

An Integrated Assessment Framework
for Considering Climate Change
Climate System

Climate changestresses•Temperature rise•Sea level rise
•Precipitation change

Feedbacks

Human &Natural Systems•Floods and droughts•Biodiversity•Animal and plant health
Environmental
impacts

Adaptation

Atmospheric
Concentrations•Carbon dioxide•Methane•Nitrous oxide•Aerosols

Mitigation

Enhancedgreenhouse effectNon-climatechange
stresses

Socio-Economic
Development Paths•Main drivers are
population,energy,economic growth,
technology and land use

Anthropogenicemissions

IPCC,2001

(IPCC 2013, Fig. SPM.1a)

Each of the last three decades has been successively warmerat the Earth’s surface than any preceding decade since 1850.
In the Northern Hemisphere, 1983–2012 was likely the warmest
30-year period of the last 1400 years (medium confidence).

(IPCC 2013, Fig. SPM.1b)

Warming in the climate system is unequivocal

(ppm)(Million km2)

Summer Arctic
Sea Ice Extent

Global Mean Sea Level(mm)

Global Mean
Temperature Change(℃)

Carbon Dioxide

GHGs, Temperatures and Sea level
have rapidly risen since the 20th Century

1900

2000
(IPCC WG1 AR5）

6

Observed Impacts

IPCC,2014

Attribution of the observed climate changeBlack: observed

Red: Simulatedwith Natural(Solar+Volcanic)+Anthropogenic(GHGs etc.)

forcings
Blue: Simulated
only with Naturalforcings

It is extremely likely (> 95%) that human influence
has been the dominant cause of the observed
warming since the mid-20th century.

(IPCC WG1 AR5）8

(IPCC 2013, Fig. SPM.7a)

Global surface temperature change for the endof the 21st century is likely to exceed 1.5°C
relative to 1850 for all scenarios

Projected Temperature Change in the 21st century(RCP2.6 and RCP8.5)

IPCC,2014

(IPCC 2013, Fig. SPM.9)

Global mean sea level will continue torise during the 21st century

Past and Future Trends of Extreme Events
Phenomena anddirection of trend

Changes occurred(typically 1950~)

Human
contribution

Likelihood of futurechanges (Late 21C)

Warmer/fewer cold
days/nights

Very likely

Very likely

Virtually certain

Warmer/more hotdays/nights

Very likely

Very likely

Virtually certain

More/longer heatwaves

Likely in someregions

LikelyVery likely

More/more intense
heavy precipitation
eventsLikely more landwith increases
than decreases

Mediumconfidence

Very likely over most
mid-latitude land
and wet tropics

More/longer drought Likely inregions

some Low confidence

LikelyIncreases in intense
tropical cyclones

Low confidence

Low confidence

More likely than notMore extreme highsea level

LikelyLikelyVery likely
12(IPCC WG1 AR5）

Co-development of climate scenarios for impact assessment- Examples of what we can provide -• Utilization of CMIP5 climate projections– Experience in coordination of the scenarios used inS-8 project (MoEJ-funded project forcomprehensive projection of climate change
impacts in Japan).
– Web database system for efficient handling of theCMIP5 data

• Provision of climate projections originallyconducted in Japan after the CMIP5 process– MoEJ’s climate projections for supporting
adaptation planning– MEXT’s large-ensemble experiments• d4PDF/d2PDF

Experience in scenario development for the S-8 project• S-8: Assessment ofclimate change impacts
and adaptation strategy onwhole Japan and local
government (funded byMoEJ)• The report which compiled
research findings were
published in March 2014.
– http://www.nies.go.jp/s8_proj
ect/symposium/20141110_s
8english.pdf

Choice of climate scenarios in the S-8 project• Emission scenario– For considering uncertainty
range, we chose RCP8.5 andRCP2.6.
– Considering on the availability ofdynamical downscaling data, we
also chose RCP4.5.

• Climate model– Among the CMIP5 models, wechose two Japanese models(MIROC5 and MRI-CGCM3.0).
– Additionally, two more GCMs （GFDL CM3 and HadGEM2-ES）
were chosen.
• Among the models withcomparatively higher ability toreproduce 20c climate, we chose
two models that could let us
consider uncertainty range oftemperature increase andprecipitation change around Japanisland.

Projected temperature change around Japan

Projected precipitation change rate around JapanGFDL CM3; HadGEM2-ES; MIROC5; MRI-CGCM3 andother 15 GCMs (RCP8.5)

Web-based climate scenario database system• Data archived– Present data (GSWP2) and future projections (CMIP3 and CMIP5; monthly anddaily)• Tools– Basic data processing (interpolation and regional trimming) and visualization

MoEJ’s climate projections to supportadaptation planning• Background and objective

Example: Temperature increase around
Japan island in this century.

– To support the development of
the first national adaptation plandue in this summer• Features of the projections– GCM（MRI-AGCM60;60km）→RCM（MRI-NHRCM20;20km）• Contribution of JMA/MRI– Present (1984-2004) and future
period (2080-2100)– Four GHG emission scenarios（RCP2.6/4.5/6.0/8.5）– Three different ΔSST patterns
based on CMIP5 data as aboundary condition– Three different physics
schemes

Both GCM outputs covering whole the world
and RCM outputs exclusively for studies on
Japan are publicized.

d4PDF by SOUSEI program funded by MEXT••••

The d4PDF consists of outputs fromglobal warming simulations by a AGCM
and from regional downscaling
simulations covering the Japan area bya RCM with horizontal grid spacing of
60 km and 20 km, respectively.
The climate of the latter half of the 20th
century is simulated for 6000 years(3000 years for the Japan area), andthe climate 4 K warmer than the preindustrial climate is simulated for 5400
years, to see the effect of globalwarming.
From large ensemble simulations,probabilistic future changes in extreme
events are available directly without
using any statistical models.
The simulation outputs are open to thepublic, which is intended to be utilized
for impact assessment studies andadaptation planning for global warming.

http://www.miroc-gcm.jp/~pub/d4PDF/

CORDEX South Asia, East Asia and Central Asia

• CORDEX– Coordinated Regional
Climate Downscaling
Experiment– 14 region domains
including S.Asia, E.Asia,and C.Asia.
– Intercomparison ofdynamical downscaling
simulations conductedby regional climate
models about 20km
spatial resolution

http://cordex.org/

Various uncertainties in impact projection
Uncertainty in GHG / socio-economic scenario

Climate projection
Naturalvariability

Impactprojection
Impactprojection

Impactmodel
uncertainty

Climatemodel
uncertainty

GHG
emission
uncertainty

Uncertainty in methods
for developing
climate scenarios

Climatescenario
uncertainty

Socio-economicscenario
uncertainty

Thank you• Kiyoshi Takahashi• National Institute for Environmental Studies• ktakaha@nies.go.jp