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Update on model development Meteo-France Meteo-France CLOUDNET workshop - Exeter 5-6/04/2004 François Bouyssel.

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Presentation on theme: "Update on model development Meteo-France Meteo-France CLOUDNET workshop - Exeter 5-6/04/2004 François Bouyssel."— Presentation transcript:

1 Update on model development Meteo-France Meteo-France CLOUDNET workshop - Exeter 5-6/04/2004 François Bouyssel

2 Summary Model outputs for CLOUDNET database Model outputs for CLOUDNET database Modifications in the cloudiness and radiation schemes should become operational soon (beginning of May) Modifications in the cloudiness and radiation schemes should become operational soon (beginning of May) Perspectives Perspectives

3 Model variables for CLOUDNET database Global model : ARPEGE (stretched mesh ~ 25 km over west Europe) Global model : ARPEGE (stretched mesh ~ 25 km over west Europe) 36h forecasts based on 00h UTC produce hourly outputs for CLOUDNET sites (nearest grid point)  fluxes, variables 1) Model 2) New fields will be provided soon (May 2004) T 2m, q 2m, U 10m, V 10m Altitude Dynamical and thermal roughness lengths Albedo Boundary layer height Downward solar and thermal fluxes 3) Currently delivered once a month  real time (?)

4 Changes in the cloudiness and radiation cloudiness and radiationschemes

5 Diagnostic schemes : Diagnostic schemes : - Precipitation (stratiform, convective) - Cloud condensates (liquid and solid) - Cloudiness Introduction Cloud condensates and cloudiness  inputs of radiation scheme Cloud condensates and cloudiness  inputs of radiation scheme q_liquid q_ice Radiation (SW, LW) Neb Change in ARPEGE since 14th April 2003

6 Malcolm Brooks, University of Reading. – R.M.S. – Norwich, 2003 Pre April~14 April~14 onwards

7 Modifications in the new cloudiness scheme Too much 0/1 cloudiness fraction Too much 0/1 cloudiness fraction Weaknesses of the current situation (Oper) : Not enough q_ice content Not enough q_ice content Modification in Xu & Randall cloudiness formulation Modification in Xu & Randall cloudiness formulation Modifications (Mod) : Convertion coefficient of potential water vapor excess to cloud condensate (  s ) dependent on q_sat Convertion coefficient of potential water vapor excess to cloud condensate (  s ) dependent on q_sat New tunings New tunings

8 Comparison of cloud condensates and cloudiness (Oper versus Mod) Cloud condensates Cloudiness

9 q_liquid q_iceNeb Mod : Oper :

10 Mod : Oper : SSMI climatology July 87-88-89 SSMI Q_ice Q_liquid Q_total

11 Oper : Mod :

12 Radiation schemes Very robust and efficient code (cost ratio with FMR around 20 !!) Very robust and efficient code (cost ratio with FMR around 20 !!) Called every time step : full consistency for cloud/radiation interactions Called every time step : full consistency for cloud/radiation interactions Improved in February 2003 : LW exchanges between atmosphere and surface Improved in February 2003 : LW exchanges between atmosphere and surface 1) Operationnel one (SW & LW) (Geleyn and Hollingsworth 1979) 2) Fouquart (SW), Morcrette(LW), Radiation : FMR (Morcrette 1989) Full radiation part called every 3 hours (SW transmissivities, LW fluxes) Full radiation part called every 3 hours (SW transmissivities, LW fluxes) LW spectrum divided into 6 spectral regions LW spectrum divided into 6 spectral regions SW spectrum divided into 2 spectral regions SW spectrum divided into 2 spectral regions

13 Comparison of LW radiation schemes with low level cloud (zoom near the surface)

14 Impact of FMR15 Global tendency of Qv Oper Mod Mod+FMR15 Zonal tendency of Qv

15 Perspectives New physical package in development for ARPEGE New physical package in development for ARPEGE  Pronostic TKE scheme  Pronostic microphysics  New convection scheme (deep and shallow) 2km AROME prototyp in development 2km AROME prototyp in development Wish to enlarge the use of CLOUDNET data : Wish to enlarge the use of CLOUDNET data :  Validation of research development  Which data could be used and associated error bars? Cloud fraction, LWP, IWP, Cloud base, PBL height,...  Is it possible to use programs to produce « quicklooks » graphics?


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