Kakushin A1B1 Meeting

26th July 2007 Julia Hargreaves, James Annan, Toru Miyama, Kaoru

Tachiiri, Shigenori Murakami,

1

JUMP

• Outline of project

• Project elements

• Approximate Time Plan

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Outline of JUMP

• JUMP is Japan Uncertainty Modelling Project. Similarity to Hadley Centre’s

“QUMP” is deliberate.

• JUMP is the intersection of S5-1 and Kakushin

3

JUMP Aims

• Uncertainty in the climate projections which have made and will be made in next few years. Probabilistic prediction.

• Atmosphere, Ocean, Ice sheet, Carbon Cycle (land and ocean).

• This year - development and evaluation of methods/ strategies.

4

JUMP Aims in pictures!

100 year

prediction

300 year

prediction

Time

Change/Impact Change/Impact

Pro

ba

bili

ty

Pro

ba

bili

ty

High-res

AOVGCM

Low-res

AOVGCM

Best Estimate

Uncertainty

range

Present

day

Uncertainty estimation using a hierarchy of models

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S5-1: Consequences of Climate Change

• Physical system - Atmosphere-Ocean.

• Moving from Global to Regional, time-scale 30-100 years

• Results required soon for use in rest of S5-1 and No modelling allowed!

• Annan and Hargreaves, GRL 2006 indicated that IPCC model range in climate sensitivity consistent with uncertainty derived from data.

• People James, jules and PD Suneet Dwivedi to join in October

6

Progress so far - S5

A single GCM:Past and

Future 30 year trends

Two different Multimodel (only 3 models) fits to past trend of the GCM

produces these forecast trends

Past trend from a single GCM (inm) Future trend from a single GCM (inm)

Weighted average forecast trend (RMSE=0.43) Simple average forecast trend (RMSE=0.42)

2m tempJ.D.Annan

Test case: Using a 3 model ensemble to predict the trend of a fourth model. The 4 models are MIROC, IPSL, HADGEM and INM.

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Traceable modelling (mostly B1)

• Methods - EnKF, Particle Filter, Emulator - James and Murakami-san

• AOGCM - Miyama-san

• Atmosphere/ocean, terrestrial carbon cycle - Tachiiri-san

• Ice sheet - no one yet

• Paleo-climate, ocean biogeochemistry - jules

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Traceable modelling MIROC3.2: atmosT42;

ocean 256x192x20MIROC3.2-LITE: atmos EMBM;

ocean 90x45x35

2m Temperature

Sea Surface Temperature

T.Miyama K.Tachiiri9

Methods

Ensemble Kalman Filter

Particle Filter Emulator

efficient maybe more expensive very cheap once created

correct in linear case copes with high nonlinearity

copes with high nonlinearity

medium difficulty to create (but we have

one! )

easy to create (and we nearly have one! )

difficult to create (and we don’t have one )

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EnKF vs. PF

Red = Correct solutionJ.D.Annan

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Atmosphere-Ocean system

• AOGCM at T42 is too computationally expensive to run ensemble to equilibrium. At least 500 years required.

• T21 AGCM+slab is possible. How do we bridge the gap, and what errors incurred by doing so?

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AOGCM work in progress• AGCM-slab ENKF tuning global average heat flux

(QFLUX) to be small

• Investigation of AGCM-AOGCM differences

[2] minus [1]

[1] Coupled Model (control)

Total Air-Sea Heat flux (W/m^2)

SLAB Ocean Model

[2] Couple Model (140 years later)

annual 1% CO2 increase

Air-sea heat flux changes in coupled model

as CO2 is increased but

remains constant in Slab model

T.Miyama

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MIROC-LITE

• New model - tune physical parameters (AO) to present day physical climatology using PF or EnKF.

• Present day “physics ensemble” potentially useful for several studies:-

✴ future, paleoclimate, ice sheet, carbon cycle

✴ Time-scale 100years +

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MIROC-LITE - work in progress

• Porting model to Altix

• Assessment of present day climate

• Using ensembles to tune model physics (soon)

Convergence of different layers in

the ocean5

6

7

8

9

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19.1

19.2

19.3

19.4

Pote

ntia

l tem

pera

ture

in d

egre

e (4

50-4

000m

)

Pote

ntia

l tem

pera

ture

in d

egre

e (0

-50m

)

0-25m

450-600m

0

1

2

3

4

18.5

18.6

18.7

18.8

18.9

0 1000 2000 3000 4000 5000

Pote

ntia

l tem

pera

ture

in d

egre

e (4

50

Pote

ntia

l tem

pera

ture

in d

egre

e (0

Year

800-1100m

1500-2000m

2500-3000m

3500-4000m

-1

0

1

2

3

4

5

6

7

8

9

18.2

18.3

18.4

18.5

18.6

18.7

18.8

18.9

19.0

19.1

19.2

0 1000 2000 3000 4000 5000

Pote

ntia

l tem

pera

ture

in d

egre

e (4

80-5

100m

)

Pote

ntia

l tem

pera

ture

in d

egre

e (0

-5m

)

Year

0-5m

480-540m

950-1070m

1970-2220m

2800-3140m

3900-4300m

4700-5100m

MIROC-LITE : 90x45xL35MIROC-LITE : 60x30xL15

K.Tachiiri

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Terrestrial Carbon cycle

• Problem with precip in EMICs - precipitation is very approximate - to what extent can we get realistic vegetation?

✴ 2-way coupling physics <-> carbon cycle

• Alternative strategy - pattern scaling of GCM runs coupled to carbon cycle model.

✴ Feedback of carbon-cycle on climate is only included through changing CO2.

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Paleo-climate

• Important for validation and crucial for providing quantification of uncertainty -> probabilistic prediction.

• Work in progress

✴ GENIE (EMIC)- combined physics and ocean biogeochemistry ensemble at LGM

✴ MIROC - is climate sensitivity the same at the LGM as today?

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LoveClim MRI

MIROCNASA/GISS

ECBILT

MOM OGCM

CCC

UVIC

CC

SM

CLIMBER

HA

DC

M3

Blue dots =Andre Paul, EGU 2007Red dots =Weber et al, CP 2007

LGM - Max. N.Atlantic. Overturning

J.C.Hargreaves

Change in AMOC between LGM

and present day is surprising uncertain in GCMS. Data

indicate that the change is small

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Time-line

Year Research Results/Papers Possible IPCC/MIROC development time-scale

2007-2008 Scoping study Methods, AOGCM-AGCM analysis, physical output of MIROC-LITE code development

2008-2009 Test casesImplementation of methods in test

cases: GENIE particle filter, tuning of MIROC-LITE to present day climate,

AGCM-AOGCM ensemble

first half; tuningsecond half: ES switched off!!!!

2009-2010 ImplementationPaleo-climate study of MIROC-LITE

ensemble, Ensemble of new version of MIROC!, carbon cycle/ ice sheet in

MIROC-LITE

scenario runs due

2010-2011

Production

Uncertainty studies with most up to date versions of the models -

production of uncertainty estimates and probabilistic predictions for IPCC

last paper deadline around end 2011 for 2013 publication?

2011-2012

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Point raised by Kawamiya-san

• Maintain awareness of TRACEABILITY!

• Transfer of information between cheaper model and more expensive model.

• This is a theme of the program, which I should have included explicitly). It is something everyone is involved in

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