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 to A global score for COSMO models - recommendations from “The Score Meeting of 20th August 2007 in Zurich” Ulrich Damrath

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

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

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

U. Damrath: Long term time series of forecast quality of COSMO-EU - COSMO GM, Offenbach 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/S 0 x100

U. Damrath: Long term time series of forecast quality of COSMO-EU - COSMO GM, Offenbach 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]

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

U. Damrath: Long term time series of forecast quality of COSMO-EU - COSMO GM, Offenbach Persistence one day before forecast day Cloud cover wind and temperature 6h-sums: precipitation Verification frequency Forecast day

U. Damrath: Long term time series of forecast quality of COSMO-EU - COSMO GM, Offenbach Verification frequency Forecast day Persistence day before forecast day

U. Damrath: Long term time series of forecast quality of COSMO-EU - COSMO GM, Offenbach 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!

U. Damrath: Long term time series of forecast quality of COSMO-EU - COSMO GM, Offenbach 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!

U. Damrath: Long term time series of forecast quality of COSMO-EU - COSMO GM, Offenbach Final definition of the score - 3 Sum over all elements: Equal weights for all elements! COSMO-index COSI = S/S 0 x100: This is not defined up to now because there is no agreement concerning the date for S 0. But it seems to be no major problem..

U. Damrath: Long term time series of forecast quality of COSMO-EU - COSMO GM, Offenbach German list: Helgoland St Peter-Ording Schleswig Fehmarn Arkona Norderney Bremerhaven Cuxhaven Hamburg Fuhlsbuettel Boltenhagen Rostock-Warnemuende Greifswald Emden-Flugplatz Bremen Neuruppin Angermuende Muenster/Osnabrueck Diepholz Hannover Braunschweig Magdeburg Potsdam Berlin-Tegel Berlin-Tempelhof Berlin-Schoenefeld Lindenberg Duesseldorf Kahler Asten Brocken Artern Leipzig-Schkeuditz Oschatz Dresden-Klotzsche Cottbus Goerlitz Aachen Nuerburg-Barweiler Koeln/Bonn Giessen Wasserkuppe Meiningen Erfurt-Bindersleben Neuhaus a.R Gera-Leumnitz Chemnitz Fichtelberg Trier-Petrisberg Hahn Frankfurt/M.-Flughafen Wuerzburg Hof Weiden Saarbruecken-Ensheim Stuttgart-Echterdingen Nuernberg Regensburg Straubing Lahr Stoetten Augsburg Muenchen, Flughafen Fuerstenzell Konstanz Kempten Hohenpeissenberg

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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