1 / 15

Update on model development Meteo-France

Update on model development Meteo-France. CLOUDNET workshop - Exeter 5-6/04/2004. François Bouyssel. Summary. Model outputs for CLOUDNET database Modifications in the cloudiness and radiation schemes should become operational soon (beginning of May) Perspectives.

alea-rowland
Download Presentation

Update on model development Meteo-France

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

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

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

  3. Model variables for CLOUDNET database 1) Model • 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 2) New fields will be provided soon (May 2004) • T2m, q2m, U10m, V10m • 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 schemes

  5. Introduction • Diagnostic schemes : • - Precipitation (stratiform, convective) • - Cloud condensates (liquid and solid) • - Cloudiness • Cloud condensates and cloudiness  inputs of radiation scheme q_liquid q_ice Radiation (SW, LW) Neb Change in ARPEGEsince 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 Weaknesses of the current situation (Oper) : • Too much 0/1 cloudiness fraction • Not enough q_ice content Modifications (Mod) : • Modification in Xu & Randall cloudiness formulation • Convertion coefficient of potential water vapor excess to cloud condensate (as) dependent on q_sat • New tunings

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

  9. q_liquid q_ice Neb Oper : Mod :

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

  11. Oper : Mod :

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

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

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

  15. Perspectives • New physical package in development for ARPEGE •  Pronostic TKE scheme •  Pronostic microphysics •  New convection scheme (deep and shallow) • 2km AROME prototyp in development • 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?

More Related