recent experiences with the inm multi-model eps scheme
Post on 11-Jan-2016
29 Views
Preview:
DESCRIPTION
TRANSCRIPT
Recent Experiences with the INM Multi-model EPS scheme
García-Moya, J.A., Callado, A., Santos, C., Santos, D., Simarro, J., B Orfila.
Modelling Area – Spanish Met Service INMEWGLAN/SREPS meeting
Federal Office of Meteorology and Climatology MeteoSwiss
9-12 October 2006
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
OutlineIntroductionSREPS system at INMMonitoring and postprocessingVerification against observation vs
Verification against analysisFurther Work and Future of SREPSConclusions
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Introduction
Triggering and Consolidating INM SREPS
NWP plan, (April 1999)SAMEX. (Summer 2000)Global boundaries; LAMs. 2000-2004Cray X1E. (2001-2005)Gathering the team
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Ensemble for Short Range
Surface parameters are the most important ones for weather forecast.Forecast of extreme events (convective precip, gales,…) is probabilistic.Short Range Ensemble prediction can help to forecast these events.Forecast risk (Palmer, ECMWF Seminar 2002) is the goal for both Medium- and, also, Short-Range Prediction.
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
What do we need?
Enough computer power.Research
Following recommendations of the workshops.
Technical difficulties.Large storage system.Database software (MARS like ECMWF).Post-processing and graphics software.Enough staff for maintenance and monitoring.Verification software.
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
SREPS at INM
72 hours forecast four times a day (00, 06, 12 y 18 UTC).Characteristics:
5 models.4 boundary conditions.4 last ensembles (HH, HH-6, HH-12, HH-18).
20 member ensemble every 6 hoursTime-lagged Super-Ensemble of 80 members every 6 hours.
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Multi-model
Hirlam (http://hirlam.org).
HRM from DWD (German Weather Service).
MM5 (http://box.mmm.ucar.edu/mm5/).
UM from UKMO (Great Britain Weather Service).
LM (Lokal Model) from COSMO consortium.
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Multi-Boundaries
From different global deterministic models:ECMWFUM from UKMO (Great Britain Weather Service)
AVN from NCEPGME from DWD (German Weather Service)
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
The team
José A. García-Moya.Carlos Santos (Hirlam, verification & graphics, web server).Daniel Santos (MM5, Bayesian Model Average).Alfons Callado (UM & grib software).Juan Simarro (HRM, LM and Vertical interpolation software).
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Thanks to…
MetOfficeKen Mylne, Jorge Bornemann
DWDDetlev Majewski, Michael Gertz
ECMWFMetview Team
COSMOChiara Marsigli, Ulrich Schättler
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Current Ensemble
72 hours forecast twice a day (00 & 12 UTC).Characteristics:
5 models.4 boundary conditions.
20 member ensemble every 12 hours
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
HP Computer Cray X1e
16 nodes, 8 MSP’s each ( ~2.4 Tf peak perf.)
Deterministic ForecastSREPSClimatic runs
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Post-processing
Integration areas 0.25 latxlon, 40 levelsInterpolation to a common area
~ North Atlantic + EuropeGrid 380x184, 0.25º
SoftwareEnhanced PC + LinuxECMWF Metview + Local developments
OutputsDeterministicEnsemble probabilistic
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Monitoring in real time
Intranet web serverDeterministic outputs
Models X BCs tables Maps for each couple (model,BCs)
Ensemble probabilistic outputsProbability maps: 6h accumulated precipitation, 10m wind speed, 24h 2m temperature trendEnsemble mean & Spread mapsEPSgrams (work in progress)
Verification: Deterministic & ProbabilisticAgainst ECMWF analysisAgainst observations
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Monit 2: all models X bcs
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Monit 3: All Prob 24h 2m T trend
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Monit 4: Spread - Emean maps
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Case Study 2006061000
More than 15 mm/6 hours
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
VerificationThe 2006 first half (6months) verification results against both references observations and ECMWF analysis are available.
Calibration: with synoptic variables Z500, T500, PmslResponse to binary events: reliability and resolution of surface variables: 10m surface wind, 6h and 24h accumulated precipitation
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Verification exerciseInterpolation to a common area
~ North Atlantic + North Africa + EuropeLat-lon Grid 380x184, 0.25º
~180 days (Jan1 to Jun30 2006).Two different references:
Analysis: ECMWF (6h and 24h det fc for Acc. Prec.)Observations: TEMP & SYNOP
Verification software ~ ECMWF Metview + Local developments
Deterministic scoresSynoptic variables: Bias & RMSE for each member & Ens Mean
Probabilistic ensemble scoresSynoptic variables: CalibrationSurface variables: Response to binary events
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Probabilistic ensemble scores
Ensemble calibration:Synoptic variables:
Z500, T500, Pmsl
Scores:Rank histogramsSpread-skill
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Rank histograms: examples
Large spreadSmall spread
Over predictionUnder prediction
Well calibrated
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Z500
Verification exercise:~ North Atlantic + North Africa + Europe, Lat-lon Grid 380x184, 0.25º~180 days (Jan1 to Jun30 2006).Analysis: ECMWF (6h and 24h det fc for Acc. Prec.)Observations: TEMP & SYNOP
Synoptic variables (here Z500) spread-skill & rank histograms against observations, show the ensemble is under-dispersive, a bit under-forecastingThe same against ECMWF analysis is very good
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Probabilistic ensemble scores
Response to binary events:Surface variables:
10m surface wind (10,15,20m/s thresholds)6h accumulated precipitation (1,5,10,20mm thresholds)24h accumulated precipitation (1,5,10,20mm thresholds)
Scores:Reliability, sharpness (H+24, H+48)ROC, Relative Value (H+24, H+48)BSS, ROCA with forecast length
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
24hAccPrec ROC & ROCA
Surface variables against observations show medium/quite good reliability and good resolution, degrading with threshold (clearly) and forecast length Here is shown 24h Accumulated precipitation performance in HH+30 forecasts: reliability with sharpness, ROC and ROCA, Brier Skill Score, Relative economic value.Verification against ECMWF analysis is much better
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Further work
The ensemble performance could be improved with some post-processing, today under development (Flattery method):
Bias correctionCalibration using Bayesian Model Averaging (BMA)
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
ROAD MAP
2003-2004 Research to find best ensemble for the Short Range
Jun 04 – Jun 05 Building Multimodel System
Jun 05-Dec 05 Mummubn/16 members
Daily run non-operational
Mar 06 Mummub 16/16 members
Once a day
Jun 06 Mummub20 members
Twice a day
July 06 Obs verfication
September 06 40 member lagged Super-
ensemble
Twice a day
October 06 BMA Calibration
January 07 Broadcast products Experimental
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
FUTURE ISSUES
Aladin and WRF as additional forecasting modelsMulti analysis from HIRLAM 3DVAR model and first guess from global model forecastsAlternative methods for multiple initial conditions Verification against observations (high resolution precipitation network over Europe)More post-process software (clustering)Statistical downscaling applied to SREPS outputsConvergence with GLAMEPS and regional THORPEXData policy aspects
OCTOBER 2006 EWGLAM/SRNWP Meetings ZURICH
Conclusions
A Multi-model-Multi-boundaries Short Range Ensemble Prediction System (MMSREPS), is preoperational at INMVerification results (2006 first half), against both observations and ECMWF analysis have been obtainedThese first results look promising:
Verification against ECMWF analysis shows very good resultsVerification against observations shows quite good results
Ensemble is under-dispersive Good response to binary events
Future of INM SREPS is still open
top related