Ulrich Pflüger & Ulrich Damrath Current state of COSMO-EU and COSMO-DE verification using Analysis, SYNOP- and upper air observations Ulrich Pflüger & Ulrich Damrath
Outline Verification against analysis Verification against SYNOPs Traditional verification - known problems Conditional verification Verification against upper air observations Some time series A problem using observations Verification against SYNOP-observations Warning: Be prepared to see a lot of red and blue lines!
Verification against analysis All levels All forecast times with an increment of 12 hours All elements on pressure levels Comparison with GME
Verification against analysis: mslp
Verification against analysis: RH 850 hPa
Verification against SYNOPs temperature 06 UTC
Verification against SYNOPs temperature 12 UTC
Verification against SYNOPs temperature 18 UTC
Verification against SYNOPs maximum temperature 06-18 UTC
Verification against SYNOPs pressure bias 06 UTC
Example for conditional verification Forecasted and observed values of surface level pressure over the region of Germany during DJF 2005/2006 (RMSE and STDV) Forecasted and observed values of surface level pressure over the region of Germany during DJF 2005/2006 observed and forecasted values lower than 1020 hPa (RMSE and STDV) Forecasted and observed values of surface level pressure over the region of Germany during DJF 2005/2006 observed and forecasted values higher than 1020 hPa (RMSE and STDV)
Conditional verification Surface weather elements Conditions concerning cloud cover pressure temperature Criteria observation below/above mean observation forecast below/above mean observation
Conditional verification (no condition, winter)
Conditional verification (high cloud covers, winter)
Conditional verification (low cloud covers, winter)
Conditional verification (high temperatures, winter)
Conditional verification (low temperatures, winter)
Conditional verification (no condition, summer)
Conditional verification (high temperatures, summer)
Conditional verification (low temperatures, summer)
RMSE Rel.Hum./Temperature (LM Area) 2005 2006 2007 2005 2006 2007
RMSE Wind Speed/Geopotential (LM Area) 2005 2006 2007 2005 2006 2007
BIAS Rel.Humidity/Temperature (LM Area) 2005 2006 2007 2005 2006 2007
Comparison: Temperature BIAS/RMSE Summer 2006/2007 in LM Area
Comparison: Temperature BIAS/RMSE Summer 2007 in COSMO-DE/LM Area COSMO-DE Area Summer 2007 BIAS RMSE LM Area Summer 2007 BIAS RMSE
Comparison: Temperature BIAS/RMSE June 2007 COSMO-DE/EU
Comparison: Temperature BIAS/RMSE July 2007 COSMO-DE/EU
Comparison: Temperature BIAS/RMSE August 2007 COSMO-DE/EU
Comparison: BIAS/RMSE of COSMO-EU Temperature, Winddirection/speed against Radiosonde and Windprofiler Data from Lindenberg 00 UTC 12 UTC BIAS RMSE BIAS RMSE BIAS RMSE BIAS RMSE BIAS RMSE BIAS RMSE
Summary Verification against analysis confirms some problems that can be shown with verification against SYNOPs Verification against SYNOPs Problems with pressure bias indicate the need of a SSO-scheme Systematic errors of temperature forecasts can be partial explained by conditional verification Verification against upper air observations Effects of pseudotemps and introduction of GME/40km can be seen clearly Cold bias of temperature within the boundary layer is a COSMO-law, especially during winter Some systematic differences between COSMO-EU and -DE exist for the boundary layer Be careful when using new observation systems to verify a model!