DEMETER

1

DEMETER Development of a European Multi-model
Ensemble System for Seasonal to Interannual
Prediction
Tim Palmer Renate Hagedorn Francisco Doblas-Reyes
2
Outline

• Hindcast production
• ? Summary of all models
• ? Estimate of ERA-40 production

Verification ? Automatic diagnostics on web
? First multi-model results
3
DEMETER
ERA40
EU and WMO programmes
4
DEMETER Hindcast production
9 member ensembles, 6 month hindcasts, 4
hindcasts per year ERA-40 initial conditions
SST and wind perturbations
Main focus 1987-1998 (1969-1986)
No SST Pert
No WP
SST Pert
- SST Pert
SST Pert
WP
- SST Pert
- WP
5
DEMETER Hindcast production
ERA-40 10 years and 7 months
ECMWF 104 2 42 hindcasts
LODYC 104 1 41 hindcasts
UKMO 94 2 38 hindcasts
CNRM 84 2 34 hindcasts
MPI 64 1 25 hc
09/86
04/97
11/86
02/97
02/95
02/96
11/92
6
Estimate of ERA-40 Production
Stream 2 Stream 3 Stream 1
7
Verification System
www.ecmwf.int/research/demeter/verification
8
Bias
9
Value
10
Anomaly Correlation Coefficient
11
Multi-model DEMETER hindcasts
ACC for Niño3 SST for Multimodel, ECMWF, MetFr,
MetOf, and LODYC
12
Multi-model DEMETER hindcasts
Tropical RPSS (JJA) for Multimodel, ECMWF, MetFr,
MetOf, and LODYC
SST
Precipitation
13
Multi-model DEMETER hindcasts
Value (Tropics, JJA) for Multimodel, ECMWF,
MetFr, MetOf, and LODYC
SST
Precipitation
Anomgt?
Anomgt?
Anomgt0
Anomgt0
14
Summary

• 5 DEMETER models are archiving into MARS
• ? Hindcasts from 1987 1996 are available
• ? Full DEMETER data set (1969-1998) not
  available
• before end of 2003
• ? free (!) online (!) data retrieval very
  likely to be
• installed and working at the end of 2002

• Wide range of diagnostic plots freely accessible
  on the
• DEMETER web site www.ecmwf.int/research/verif
  ication

• First results demonstrate value of multi-model
  approach