Ulrich Damrath

1. Long-term trends of the quality of COSMO-EU forecast expressed as the universal score COSI and others scores for temperature 2 m and wind 10 m- related toA global score for COSMO models -recommendations from “The Score Meeting of 20th August 2007 in Zurich” Ulrich Damrath

2. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 Outlook • The COSMO-Index COSI • Time series of the index and ist parts @ DWD starting @ 2003 • Time series of RMSE-values starting @ 2000 • Time series of BIAS-values starting @ 1994

3. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 Approach Application of a score like the UK-index - basic values Continuous elements Wind Skill score for wind and continuous elements related to persistence Skill score for categorical elements related to chance

4. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 Approach Application of a score like the UK-index - final score

5. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 Scores in MOVI and UKMO • Continuous parameters: Reduction of variance RV = 1 – (RMSE prog / RMSE ref)2 where ref = persistence • Categorical parameters: ETS • ETS = (R – „chance“) / (T –“chance“) R= number of obs events correctly forecast T = number of events which were either observed or forecasted global score S like COSMO-index COSI = S/S0 x100

6. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 Parameters • total cloud amount [threshold: 0-2, 3-6, 7-8 temperature [t2m, later: tmin, tmax] • 10m- windvector • precipitation [thresholds: 0.2, 2, 10 mm/6h]

7. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 Verification frequency • Every 3h • T2m, 10m-wind and cloudiness: • @ 00, 03,…, 18, 21 UTC later on: tmin & tmax over 12h • 6h-sums: precipitation

8. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 03 06 09 12 15 18 21 24 Verification frequency • Cloud cover wind and temperature • 6h-sums: precipitation Forecast day 03 06 09 12 15 18 21 24 Persistence one day before forecast day 06 12 18 24

9. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 Final definition of the score: 1 Continouos elements, sum over 8 time steps: (start: vv=3, end: vv=24, step: 3) Equal weights for all forecast times!

10. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 Final definition of the score - 2 Categorical elements, sum over N time steps: (start: vv=vvb, end: vv=vve, step: vvs) Cloud cover: vvb=3, vve=24 vvs=3 Precipitation: vvb=6, vve=24 vvs=6 Equal weights for all forecast times and categories!

11. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 Final definition of the score - 3 Sum over all elements: Equal weights for all elements! COSMO-index COSI = S/S0 x100: This is not defined up to now because there is no agreement concerning the date for S0 . But it seems to be no major problem..

12. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 German list: 10015 Helgoland............. 10028 St Peter-Ording........ 10035 Schleswig............. 10055 Fehmarn................ 10091 Arkona................ 10113 Norderney.............. 10129 Bremerhaven........... 10131 Cuxhaven............... 10147 Hamburg Fuhlsbuettel.. 10161 Boltenhagen............ 10170 Rostock-Warnemuende.... 10184 Greifswald............. 10200 Emden-Flugplatz....... 10224 Bremen................. 10270 Neuruppin.............. 10291 Angermuende............ 10315 Muenster/Osnabrueck.... 10321 Diepholz............... 10338 Hannover............... 10348 Braunschweig........... 10361 Magdeburg.............. 10379 Potsdam................ 10382 Berlin-Tegel........... 10384 Berlin-Tempelhof....... 10385 Berlin-Schoenefeld..... 10393 Lindenberg............. 10400 Duesseldorf............ 10427 Kahler Asten........... 10453 Brocken................ 10460 Artern................. 10469 Leipzig-Schkeuditz..... 10480 Oschatz................ 10488 Dresden-Klotzsche...... 10496 Cottbus................ 10499 Goerlitz............... 10501 Aachen................. 10506 Nuerburg-Barweiler..... 10513 Koeln/Bonn............. 10532 Giessen................ 10544 Wasserkuppe............ 10548 Meiningen.............. 10554 Erfurt-Bindersleben.... 10557 Neuhaus a.R. .......... 10567 Gera-Leumnitz.......... 10577 Chemnitz............... 10578 Fichtelberg............ 10609 Trier-Petrisberg....... 10616 Hahn................... 10637 Frankfurt/M.-Flughafen. 10655 Wuerzburg.............. 10685 Hof.................... 10688 Weiden................. 10708 Saarbruecken-Ensheim... 10738 Stuttgart-Echterdingen. 10763 Nuernberg.............. 10776 Regensburg............. 10788 Straubing.............. 10805 Lahr................... 10836 Stoetten............... 10852 Augsburg............... 10870 Muenchen, Flughafen.... 10895 Fuerstenzell........... 10929 Konstanz............... 10946 Kempten................ 10962 Hohenpeissenberg.......

13. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD COSMO-EU V3.19 V 3.22 T 2m SSO

14. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Scores for day 1

15. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Scores for day 2

16. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Scores for day 3

17. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Scores for different forecast times

18. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Cloud cover for day 1

19. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Cloud cover for day 2

20. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Cloud cover for day 3

21. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Wind vector for day 1

22. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 RMSE - Wind speed for vv=12

23. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 RMSE - Wind speed for vv=24

24. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 RMSE - Wind speed for vv=36

25. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Wind vector for day 2

26. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Wind vector for day 3

27. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Temperature for day 1

28. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 RMSE - Temperature

29. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 BIAS - Temperature

30. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 RMSE - Temperature

31. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 BIAS - Temperature

32. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Temperature for day 2

33. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Temperature for day 3

34. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Precipitation for day 1

35. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Precipitation for day 2

36. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 COSI@DWD - Precipitation for day 3

37. U. Damrath: Long term time series of forecast quality of COSMO-EU -COSMO GM, Offenbach 2009 Summary • Replacement of LM with COSMO-EU lead at first to remarkable deterioration of COSI. • Main effect: worse results concerning wind which is the element that contributes most to the score (not in the sense of the weight but in the sense of it has a higher value compared to the other elements) • A lot of model changes lead to a remarkable improvement of COSI. • Changes of cloud microphysics brought essential improvement of temperature forecasts. • The new diagnostic scheme for T2m amplified this effect. • The new SSO-scheme was a jump! • Now COSI is better for all days compared with the beginning of calculation of the score.