Summary of WG3 activitiesPhysical Aspects

Federico Grazzini ARPA Emilia- RomagnaServizio Idro Meteo Clima (SIMC)

WG3 activities

• Boundary layer (5 wp)• Radiation (1wp)• Deep convection and grid scale precip (3 wp)• Lower boundary conditions (3 wp)• Diagnostic (2 wp)

http://cosmo-model.cscs.ch/content/tasks/workGroups/wg3/workPlans.priv/workPlan2008.htm

PBL

Revision of 2Tm diagnostic (implemented in version 4.3) Revision of the surface transfer scheme New concept for a roughness layer extension of the current turbulence

scheme Introduction of the mixed water/ice phase in the moist turbolent scheme and

stat. condensation scheme(Raschendorfer, DWD)

Test and implementation of Lott and Miller sub-grid scale orography scheme (SSO) (Schulz,DWD)

Revised parameter (turlen, SGS cloud) settings in the COSMO-DE boundary layer (TKE) scheme (Seifert, DWD)

Hovmöller diagramms or precipiation rate1 May to 9 June 2008

• In the operational COSMO-DE almost no diurnal cycle, the afternoon maximum is very weak.

• Clear improvement in the model behavior using the modified PBL parameters. Reduced nocturnal drizzle, better afternoon maximum

Courtesy of A. Seifert

Radiation

A new parameterization for ice cloud radiative properties has been developed and tested and introduced in the model (Bozzo, Univ. Bologna)

A new scheme accounting for topographic effect on radiation (Buzzi, MeteoSwiss)

A scheme to account for solar zenith angle in cloud overlap treatment (Di Giuseppe, ARPA-SIM)

CONVECTION Implementation of Tiedtke ECMWF scheme (Mercogliano, CIRA)

Diagnostic of COSMO convective scheme (Grazzini, ARPA-SIM)

Modification of the Tiedtke(89) convection scheme: coexistence of cloud ice/water, changes in convective cloud condensate detrainment, changes in the RH env threshold for evaporation (implemented in version 4.4 Mironov, DWD)

Example 11 June 2007

avg 2.8 mm avg 3.9 mm avg 1.9 mmmax 44 mm max 274 mm max 27 mmavg 3.1 mmmax 60 mm

observation control new scheme

accumulated precipitation in mm

Courtesy of A. Seifert

SURFACE PROCESSES

Improving the multi-layer soil model TERRA (Vogel, DWD)

Implementation of mosaic approach (Ament, MeteoSwiss)

Impact of different Leaf area index specification (Di Giuseppe, ARPA-SIM)

Competence to be transferred to the new PP COLOBOC

DIAGNOSTIC

Diagnostic tools to analyse and understand the main forecast errors of the COSMO model focussing on the interaction between PBL and surface (Bonafè, ARPA-SIM)

Courtesy of G. Bonafè and G. Vogel

Courtesy of G. Bonafè and G. Vogel

Courtesy of G. Bonafè and G. Vogel

Courtesy of G. Bonafè and G. Vogel

Courtesy of G. Bonafè and G. Vogel

Courtesy of G. Bonafè and G. Vogel

Courtesy of G. Bonafè and G. Vogel

Issues

• More robust diagnostic, possibly on different areas/domains

• Exchange of model data or diagnostic recipes?• There should be a stronger feedback between research

activities and operational implementations…..• A step toward simplification: a reference version ?