Introduction of TOUGOU theme C-Integrated Climate ProjectionIntegrated Research Program for Advancing Climate Models

Izuru TAKAYABU, Masayoshi ISHII, Toshiyuki NAKAEGAWA,Hidetaka SASAKI (MRI) and Kazuhisa TSUBOKI (ISSE)

V５.5 2017/08/17

In Japan, not only the citizens, but also cats keep high interest on
extreme weather’s increase perhaps caused by the climate change…

Background of the design of TOUGOU
program• International– IPCC AR6 reports are scheduled to be published in2021.
• Shake hands among WGI. II. and III are strongly
recommended in AR6 scoping meeting and also in IPCC
46th meeting.
– WGI: The physical science basis– WGII: Impacts, adaptation and vulnerability– WGIII: Mitigation of climate change– Paris agreement has been engaged in Dec. 2015.

Background of the design of TOUGOU
program• Domestic– Nov. 2015: “National Plan for Adaptation to the Impacts ofClimate Change” has been decided by the Cabinet.

• Vision of society: By promoting adaptation measures to climatechange impacts, to build a secure, safe and sustainable societythat is able to minimizing and avoiding damage for life of citizens,properties, economics, and natural environment due to its impacts,
and to be resilient against damage.
–  A-PLAT (Climate change adaptation platform) has been prepared.

– May 2016: “Global Warming Adaptation Plan” has been
decided by the Cabinet, following to Paris agreement.
•  APAN (the Asia Pacific Adaptation Network)

The targets of TOUGOU theme C are• To arrange the authorized climate change
projection data around Japan Islands.
• To prepare a high accuracy, local scale climatechange data, especially of extreme events.
– Heavy precipitation events in summer monsoon
season– Tropical cyclones

Why we need the authorized data
Producers

CMIP5/6

Climateresearchers

ESD
DDS(Downscale)users
Deliverdata
demandDown-scalers
Authorized data

Agriculture
HealthHydrology
Ecology

CitizensTV
Local
governmenti

Impact study
researchers

End Users

funding

MEXT, MAFF, MOE, JMA ・・・（Relevant government authorities）

How to prepare the authorized data
We have to consider…

• How to handle the variety of the scenarios.
• Compare pros and cons of ESD and DDS.
• Clarify the position of MRI-AGCM/NHRCM DS
system in CMIP5 model results.
• Crossing boundary between the ministries andproduce a dataset family usable for theclimate change impact study researchers
To respond to the various demand from users,
we arrange the projection data by considering its
temporal and space scale.

Next, on heavy precipitation …
Change of Baiu precipitation behavior

ΔＳＳＴ

HFA_rcp85
CMIP5 mean
ΔSST pattaern

mm/dNormalize by ΔSAT

Change to
CMIP3 mean
ΔSST patternand calc.
When we change SST pattern from CMIP5 to
CMIP3, precipitation around Japan Isls., andtropical NW Pacific increase Which explain the difference in theprecipitation pattern between CMIP3 and 5Calc.
done byCMIP3condition

Change of Baiu precipitation behavior

The effect of Air Sea coupling

JJA meanprecip.
UV850hP(Chenge)b) 20km semicoupleda) 20km AGCM

10-20N, 110-140E

b-a

When we use the air-sea interaction,
Precipitation in• Tropical NW Pacific• Around Japan Isls.
Increase Difference between CMIP
models decrease× 20km AGCM (YS)
● 20km Semi-coupled (YS)
× 60km AGCM (YS)
● 60km Semi-coupled (YS)
○ CMIP5 AOGCM

Rainfall distribution of NHRCM05/02
Potential of high resolution（Courtesy of Morimoto andWideareaNakakita 2017) (DPRI)
model. Here 5km and 2km gridmodel results are comparedHIROSHIMA flood (Aug. 2014)

Story line approach(by PGWD)
Water content (g/kg)

Stability

Here we use δx=500m model andcatch the heavy precipitation event
6hourly
precipitation
patterns ofHIROSHIMA floodcase.
 Control experiment.

All ensemble cases We adopt all thesecalculations to build anensemblePrecipitation amounts change

Area averaged precipitation amount change areshown in the figure.
Horizontal axis : precipitation of present condition



Vertical axis: Precipitation of the future condition.

Blue dots: Stability not changed.

(mm)積算降水6h

将来実験 赤( と)中立実験 青( の)領域平均

Area mean precipitation (6 hour)

Red dots: Stability and WV has changed to the futurecondition
現在実験の領域平均6h積算降水 (mm)Finally, Tropical Cyclones…

Change of all TC occurrence frequency

Knutson et al. (2015) [HiRAM+ hurricane model]

d4PDFの4℃上昇実験

Sugi et al. (2016) [多種MRI-AGCM3.2]

Roberts et al. (2015) [MetOffice GA3.0]

The common results are,• Decrease  WNP,SIO, SPA• Increase  Around Hawaii

Courtesy of Yoshida, 2017

Occurrence frequency change of Cat-4/5 TC
Knutson et al. (2015) [HiRAM+ hurricane model]

Present study

Sugi et al. (2016) [多種MRI-AGCM3.2]

Common results here are,* Decrease  NWP, SPA* Increase  From south of Japan
Isls. to Hawaii Isls.
We cannot discuss on the details
of TC by using only GCM. Thus, weuse high resolution regional model.
Courtesy of Yoshida, 2017

Story line approach (by PGWD)

ALL and NAT exps. of Haiyan
20km

5km1km
NAT： SST and stability is set to 150 years ago.
ALL： Calc. has been done in present condition.

(Takayabu et al., 2015 ERL)

Difference of strength of typhoon
Haiyan between ALL and NAT exps.
MCP become
lower in ALL

2.89 ± 2.06m/s

15/16

NAT

-6.44 ± 4.98hPa
15/16

最大風速が大きいALL
Results of 1km grid WRF model (16 ensembles)(Takayabu et al., 2015 ERL)

Difference of storm surge among ALLand NAT exps.
Max 3.8m （mean: 2.19m）

NAT

Strom surge height around
Tacloban increase about 20% in
ALL cases, compared to NAT cases.

Max 4.27m （mean: 2.60m）

ALL(Takayabu et al., 2015 ERL)The targets of TOUGOU theme C are• To arrange the authorized climate change
projection data around Japan Islands.
• To prepare a high accuracy, local scale climatechange pattern data.
– Especially extreme events such as heavy
precipitation and tropical cyclones.

• We also aim at co-working with foreigncountries.