ENSEMBLES – a European project forclimate change modelling
ENSEMBLE-based Predictions of Climate Changes andtheir Impacts
Ulrich Cubasch
Meteorologisches Institut
Freie Universität BerlinGermany

Structure Review of TAR results
 New developments
 IPCC recommendations for the AR4
 ENSEMBLE – The European climatemodelling projectReview of TAR results

CCSR/NIES

The globally averaged changeof the near surface
temperature relative to theyears 1961-1990,
simulated by 3d globallycoupled ocean-atmospheremodels
MRI

The temperature change for all SRES scenarios simulated
by a simplified model representing all the 3d-models

The global temperature change for the SRES A2 scenario

CO2 emissions, concentration andtemperature evolution for variousstabilization scenarios

New developments

Probabilistic approachDecadal probability density functions (PDF) of a transient
greenhouse gas ensemble: each PDF consists of 160 NAO index
realisations.
Paeth et al, 1999 – in the TAR

Probability density functions of temperature change
simulated with the Hadley Centre model
Stott and Kettleborough, 2002

Probability density distribution of climate projection
Allen & Ingram, 2002

IPCC recommendations for theAR4

Experiment 1 (20C3M)

CO2

Forced 20th century simulation to 2000

Fix all concentrations at year 2000 values (CO2 ~ 360 ppm)

Run for 21st century to 2100

Experiment 2 (750 ppm stabilization)

CO2



Scenario A1b



Run for 21st century to 2100 (CO2 ~ 720 ppm)

Fix all concentrations at this level to 2200
A2

Experiment 3 (550 ppm stabilization)

CO2



Scenario B1

Run for 21st century to 2100 (CO2 ~ 550 ppm)

Fix all concentrations at this level to 2200
A2A1b

Experiment 4CO2



Scenario A2Run for 21st century to 2100 (CO2 ~ 860 ppm)

Experiments for IPCC AR4Approved by IPCC
Letter of S. Solomon 8.12.2003
0.

Control simulation•

Forced 20th century simulation + fixed concentrations for 21st century (20C3M)•

Beginning with 1., but then Scenario A1b for 21st century + fixed concentrations for 22nd century (750 ppmstabilization)•

Beginning with 1., Scenario B1 for 21st century + fixed concentrations for 22nd century (550 ppmstabilization)•Scenario A2 for 21st century•

1% CO2 increase per year until doubling and quadrupling, then fixing concentration (CMIP)•2*CO2 equilibrium run with a slab ocean

ENSEMBLE – The European climate
modelling project

after D. Griggs, Hadley Centre (project coordinator)

ENSEMBLES

A five year project under EC Framework Programme VI

Funding from EC of 15 million Euros

72 partners from EU, candidate countries, Switzerland, Australia, USEight Research Themes

ENSEMBLES
Strategic Objectives
Develop an ensemble prediction system based on the principal state-ofthe-art high resolution, global and regional Earth System models,validated against quality controlled, high resolution gridded datasets forEurope, to produce for the first time, an objective probabilistic estimateof uncertainty in future climate at the seasonal, decadal and longer
timescalesQuantify and reduce uncertainty in the representation of physical,
chemical, biological and human-related feedbacks in the Earth System

Maximise the exploitation of the results by linking the outputs to arange of applications, including agriculture, health, food security,energy, water resources, insurance and risk management

ENSEMBLES
Scientific Objectives 1

Build an integrated European capability to predict climate changes, andconsequent socio-economic impacts, on seasonal, decadal and longer
timescales, using a probabilistic multi-model approach to climate
scenario construction.

Assemble Earth System models including the various components andthe interactions between them.



Develop high resolution regional climate models for Europe along withquality controlled gridded climate datasets for EuropeAdvance understanding of the key processes and feedbacks that governchanges in climate, and related consequences, with particular attention
to extreme events and the possibility of abrupt climate change.

ENSEMBLESScientific Objectives 2
Develop a comprehensive approach to the validation of climate change
ensembles and the impact assessments, which includes the exploitationof seasonal to decadal predictability studies, thereby providing for the
first time a sound, quantitative measure of the confidence in futurescenariosEstimate quantitatively the predictability of climate changes andvariations, especially those associated with flood and drought, on
timescales of seasons, decades and beyond, and to provide better
estimates of the likelihood of abrupt, catastrophic climate change in thecoming century.

Provide detailed probabalistic assessments of the impacts of climatechange at high resolution over Europe.

Disseminate the knowledge gained during the project to policy makers,scientists, and the public.

ENSEMBLES Research Themes
RTNameCo-ordinators

0

Project integration, management and promotion

Dave Griggs

1

Development of the Ensemble Prediction System

James Murphy, Tim Palmer

2A

Production of seasonal to decadal hindcasts and2B

climate change scenarios (Model Engine Part 1)

Guy Brasseur, Jean-François Royer

Production of Regional Climate Scenarios for Impact

Clare Goodess, Daniela JacobAssessments (Model Engine Part 2)34Formulation of very high resolution Regional Climate

Jens Christensen,

Model Ensembles for Europe

Markku Rummukainen

Understanding the processes governing climate

Julia Slingo, Herve le Treutvariability and change, climate predictability andthe probability of extreme events
5

Independent comprehensive evaluation of theAntonio Navarra, Albert Klein Tank

ENSEMBLES simulation-prediction system against observations/analyses
6Assessments of impacts of climate change

Jean Palutikof, Andy Morse7

Scenarios and Policy Implications

Richard Tol, Roberto Roson

8

Dissemination, Education, and Training

Martin Beniston,Christos Giannakopolousinstitutemodel

GCAM

HadGEM 10 atm,1/30 oc

HadleyHadGEM new

INGVECHAM5-OPA

IPSL + UCLASTRIPSL-model

CNRM

Arpege + ISPLoc

FUB

EGMAM
T30L39 at, T42eq.ref. oc

MPIMET

ECHAM5 MA+OM1DMIECHAM5 MA+OM1NERSCBergen modelUiO

Oslo model

Models and institutes involved
in ENSEMBLES scenario
experiments

ENSEMBLES Currently at contract negotiation stage

 Project will be managed by a Management Board

under the terms of a Consortium Agreement
 Expected start date 1 April 2004?

 First meetings have already been held because of the tightdeadlines imposed by IPCC

Summary Everything is geared up and ready to go for the IPCC AR4challenge