Overview

Only IFS cycles with  TIGGE related changes are listed (changes to the previous version are in bold)

N/A means that the information is not available for the model. 

For full model update documentation please refer to the official page Changes in ECMWF model


1. Ensemble Version


Version Identifier Code40r131r1
Date of first implementation of this version

 

 

Please provide a short description of the Ensemble Prediction SystemGlobal ensemble system that simulates initial uncertainties using singular vectors and perturbations from an ensemble of data assimiliations.  Model uncertainties represented with SPPT and SKEB. Based on 51 members, run twice-a-day up to day 15,  (extended to 32 days twice weekly, on Mondays and Thursdays).Global ensemble system that simulates initial uncertainties using singular vectors and model uncertainties due to physical parameterisations using a stochastic scheme. Based on 51 members, run twice-a-day up to day 15, with at 00UTC a coupled ocean system from day 10 to day 15 (extended to 32 days once a week, on Thursdays).
Research or Operational? If not operational, are there any plans to become so?OperationalOperational
Global or Regional EPS? (See section 7 for items specific to regional EPS)GlobalGlobal
Data time of first forecast run 

Date of last forecast with this version (if applicable)

Data time of last forecast run (if applicable)

Is there a higher-resolution control forecast available? (If yes, this should be described in a separate sheet of this spreadsheet.)NoNo
Brief summary of main changes from previous version (keywords).Coupling to NEMO ocean model, 91 levels with top a 1 Pa, higher horizontal resolution, EDA initial perturbations, revised model uncertainty representationN/A - First version listed



2. Configuration of the EPS


Horizontal resolution of the model. (Where variable resolution is used, please describe in full.)TL639TL399
Horizontal configuration and resolution of the output gridTL639 L91 for day 1 to day 10 (leg 1) and TL319 L91 after day 10 (leg 2)
The resolution archived is N320 reduced gaussian grid for leg1 and N160 reduced gaussian grid for leg2.
T399 L62 for day 1 to day 10 (leg 1) and T255 L62 for T+246 to day 15 (leg 2)
The resolution archived is N200 reduced gaussian grid for leg1 and N128 reduced gaussian grid for leg2.
Number of model levels9162
Type of model levels (eg sigma)sigmasigma
Forecast length and forecast step intervalT+0h to T+360h at 6hT+0h to T+360h at 6h
Runs per day (Times in UTC)2 (00, 12)2 (00, 12)
Is there an unperturbed control forecast included? (Y/N)YY
Number of perturbed ensemble members (excluding control)5050
Integration time step20 min for leg 1 and 45 min for leg 230 min
Top of model - model section~0.01hPa~5hPa
Is model coupled to an ocean model?YesNo
If yes, please describe ocean model briefly including any ensemble perturbations appliedNEMO 1deg, 5 different ocean analyses
Additional comments




3. Initial conditions and Perturbations


Data assimilation method for control analysis4D-Var 12h window4D-Var 12h window
Resolution of model used to generate control analysisTL1279L137TL799L91
Control variables used in data assimilationN/AN/A
Ensemble initial perturbation strategySingular Vectors (Total energy norm) and ensemble of data assimilations (EDA)Singular Vectors (Total energy norm)
Optimisation time in forecast (if applicable)
T+48
Horizontal resolution of perturbations (if different from model resolution)singular vectors T42L91 and TL399L137 for EDAT42L62
Initial perturbed areaglobalExtra tropical (<30S, >30N) + up to 6 tropical areas
Are perturbations to observations employed? (Y/N)YesNo
Perturbations added to control analysis or derived directly from ensemble analysisAddedAdded
Perturbations in +/- pairs? (Y/N)YesYes
Additional commentsN/AN/A



4. Model Uncertainty Perturbations


Is model physics perturbed?  If yes, briefly describe method(s).Y. Uses Stochastically Perturbed Parameterization Tendencies (SPPT) and Stochastic Kinetic Energy Backscatter (SKEB)Y. Stochastic perturbation of physics tendency by factor in range [0.5,1.5]
Do all ensemble members use exactly the same model version, or are, for example, different parameterisation schemes used? Please describe any differences.SameSame
Is model dynamics perturbed? If yes, briefly describe method(s).NoNo
Are the above model uncertainty perturbations applied to the control forecast? NoNo
Additional commentsN/AN/A



5. Surface Boundary Perturbations


Perturbations to sea-surface temperature?  If yes, briefly describe method(s).Yes, 5 different ocean analysesNo
Perturbations to soil moisture?  If yes, briefly describe method(s).Yes, from EDANo
Perturbations to surface wind stress or roughness?  If yes, briefly describe method(s).NoNo
Any other surface perturbations?  If yes, briefly describe method(s).NoNo
Are the above surface perturbations applied to the control forecast?N/AN/A
Additional commentsN/AN/A



6. Other details of model


Description of model grids.Linear gridLinear grid
List of model levels in appropriate coordinatesOperational configurations of the ECMWF Integrated Forecasting SystemOperational configurations of the ECMWF Integrated Forecasting System
What kind of Large scale dynamics is in use (e.g. gridpoint semi-Lagrangian)? Spectral semi-lagrangianSpectral semi-lagrangian
What kind of boundary layer parametrization is in use?

Moist EDMF with Klein/Hartmann stratus/shallow convection criteria

IFS documentation

Moist EDMF with Klein/Hartmann stratus/shallow convection criteria

IFS documentation

What kind of convection parametrization is in use?

Tiedtke 89, Bechtold et al 2004 (QJ) which improved the triggering

IFS documentation

Tiedtke 89, Bechtold et al 2004 (QJ) which improved the triggering

IFS documentation

What kind of large-scale precipitation scheme is in use?IFS documentationIFS documentation
What Cloud scheme is in use?

Tiedtke 93 prognostic cloud fraction

IFS documentation

Tiedtke 93 prognostic cloud fraction

IFS documentation

What kind of land-surface scheme is in use?

HTESSEL

IFS documentation

HTESSEL

IFS documentation

How is radiation parametrized?IFS documentationIFS documentation
Other relevant details?N/AN/A



7. Regional Ensemble specifics
N/AN/A
Regional domain descriptor (lat/long of boundaries)

Normal source of boundary conditions

Are boundary conditions perturbed?

Specification of boundary conditions required.

Are boundary condition requirements compatible with any other global models or standards? If so, please describe

Are initial conditions downscaled from a global analysis or is a regional analysis used?

Is regional ensemble a downscaling of global ensemble perturbations, or are specific regional perturbations calculated?

Additional comments




8. Further Information


Scientific contactECMWF Service DeskECMWF Service Desk
URLs for Scientific documentationIFS documentationIFS documentation
Technical contact pointECMWF Service DeskECMWF Service Desk
URLs for Technical documentationIFS documentationIFS documentation
Other contact pointsECMWF Service DeskECMWF Service Desk
URLs for system documentationUser guide to ECMWF forecast productsUser guide to ECMWF forecast products
Data policy of originating centre for usage of data in TIGGEUsers of the ECMWF data sets are requested to reference the source of the data in any publication, e.g. "ECMWF ERA-40 data used in this study/project have been provided by ECMWF/have been obtained from the ECMWF Data Server".Users of the ECMWF data sets are requested to reference the source of the data in any publication, e.g. "ECMWF ERA-40 data used in this study/project have been provided by ECMWF/have been obtained from the ECMWF Data Server".



9. TIGGE Specific Information


Version Identifier Code

Date of first forecast in TIGGE

Data time of first forecast run in TIGGE

Date of last forecast in TIGGE

Data time of last forecast run in TIGGE

Is there a higher-resolution control forecast included in TIGGE? If so give tab name where it is described.Yes, there is a control forecast run at TL639 and a high resolution forecast run at TL1279Yes, there is a control forecast run at T399 and a high resolution forecast run at T799

Key reference papers for EPS

  • Buizza, R., & Palmer, T. N., 1995: The singular-vector structure of the atmospheric general circulation. J. Atmos. Sci., 52, 9, 1434-1456. 
  • Molteni,F., Buizza,R., Palmer,T.N. and Petroliagis,T., 1996: The ECMWF Ensemble Prediction System: Methodology and Validation Q.J.R Meteorol.Soc. (1996) Vol 122, pp 73-119. 
  • Buizza, R., Miller, M., & Palmer, T. N., 1999a: Stochastic representation of model uncertainties in the ECMWF Ensemble Prediction System. Q. J. R. Meteorol. Soc., 125, 2887-2908.
  • Buizza, R., Bidlot, J.-R., Wedi, N., Fuentes, M., Hamrud, M., Holt, G., & Vitart, F., 2007: The new ECMWF VAREPS (Variable Resolution Ensemble Prediction System). Q. J. Roy. Meteorol. Soc., 133, 681-695.