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Federal Department of Home Affairs FDHA Federal Office of Meteorology and Climatology Meteo. Swiss

Federal Department of Home Affairs FDHA Federal Office of Meteorology and Climatology Meteo. Swiss Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier COSMO-GM, Roma, 5. 9. 2011

Agenda • Motivation • Status of the ARPA-SIM collaboration • Domain and orography filtering

Agenda • Motivation • Status of the ARPA-SIM collaboration • Domain and orography filtering • Namelist choices • Some results • Summary • Future COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 2

Motivation for COSMO-1 • Operational target is for 2015 • Why increase the grid

Motivation for COSMO-1 • Operational target is for 2015 • Why increase the grid resolution? - improve representation of forcing (e. g. topography, land use) - better capture non-linear interaction between different scales (e. g. convection) - improve use of observing systems in the assimilation step • Focus mainly on Alpine region and Alpine specific problems COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 3

Target: COSMO-1 suite in 2015 IFS boundary conditions 10 km grid size, 140 layers

Target: COSMO-1 suite in 2015 IFS boundary conditions 10 km grid size, 140 layers 4 x daily 8 x daily COSMO-1 + 24 hours forecasts 1 km grid size, 100 layers 1040 x 700 grid points COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 4

Status of the ARPA-SIM collaboration √ Common domain • Test if a common configuration

Status of the ARPA-SIM collaboration √ Common domain • Test if a common configuration can be used and a common evaluation of results operated • Nesting strategy compare C-1 in C-7 with C-1 in C-2 • Decrease damping in upper layers cf. Wolfgang Langhans 1) • Tune the orographic filtering to the stability of the dynamics • Investigate the sensitivity to the asymptotic turbulent length scale and the vertical level distribution 1) Convergence of numerical simulations of linear hydrostatic gravity wave, March 11, 2011 COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 6

Orography filtering (2 extremes) 4 Dx Raymond filter + XSO 1) 750 m COSMO-1

Orography filtering (2 extremes) 4 Dx Raymond filter + XSO 1) 750 m COSMO-1 COSMO-2 COSMO-7 1) e. Xtra filter only for masked high Rhône V. Steps of Orography COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Rhine Guy de Morsier 7

Gradient of orography a) NO filter, max. 36°, mean 6° b) Std filter, max.

Gradient of orography a) NO filter, max. 36°, mean 6° b) Std filter, max. 25°, mean 4. 4° c) 400 m xso, max. 20°, mean 4. 2° a) b) d) 300 m xso, max. 18°, mean 3. 8° Compare (CH) to: COSMO-7: max. 4°, mean 1. 1°! COSMO-2: max. 15°, mean 2. 8° near Mt Blanc c) COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss d) Guy de Morsier 8

Large Alpine Domain 698 x 528 gridpoints CPU of COSMO-2 * 4 COSMO-GM, Roma

Large Alpine Domain 698 x 528 gridpoints CPU of COSMO-2 * 4 COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss 300 m filter: max. gr. 18° C-1 with 750 m filter: 25° COSMO-2: 15° Guy de Morsier 10

Orographic spectra C-2 COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration

Orographic spectra C-2 COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss 3“ Guy de Morsier 11

Namelist choices Bold for C-2 operational RED = C-1 Dynamics • • • time

Namelist choices Bold for C-2 operational RED = C-1 Dynamics • • • time step (Dt=10 sec, C-2=20) advection (SL, Bott 2, l 3 dstrang, lva_impl_dyn) If possible NO horizontal diffusion divergence damping (xkd=0. 1/0. 05/0. 01) best choice: upper boundary condition (nrdtau=5/2) *Dt: e-folding time for damping at the model top Physics • turbulence (itype_turb=3) COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 12

COSMO-1 cases A. Storm Carmen 12 November 2010 with different orographic smoothing needs horizontal

COSMO-1 cases A. Storm Carmen 12 November 2010 with different orographic smoothing needs horizontal diffusion (1 slide) B. Convective case 29 May 2010 with/without horizontal diffusion different advection codes C. Stratus case of 27 October 2009 without horizontal diffusion (no slides) COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 13

A. Energy spectra CARMEN (12. 11. 2010) with hor. dif. 24 h forecast (u,

A. Energy spectra CARMEN (12. 11. 2010) with hor. dif. 24 h forecast (u, v, w) from 6 to 10 km height Similar results for smaller time steps COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 14

B. Convective case with COSMO-1 hd_corr_u_in=0. 5 NO horizontal diffusion COSMO-GM, Roma / Sept.

B. Convective case with COSMO-1 hd_corr_u_in=0. 5 NO horizontal diffusion COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 15

Test with a modified advection (U. Blahak) ~ 15 m/s ! Maximum nur noch

Test with a modified advection (U. Blahak) ~ 15 m/s ! Maximum nur noch ~ 3 m/s ! COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 16

B. Convective case with COSMO-1 Uli Blahak modif. advection NO horizontal diffusion COSMO-GM, Roma

B. Convective case with COSMO-1 Uli Blahak modif. advection NO horizontal diffusion COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 17

[ m 3 ] B. Convective case with COSMO-1 001: Uli Blahak modif. advection

[ m 3 ] B. Convective case with COSMO-1 001: Uli Blahak modif. advection 002: with horizontal diffusion 003: NO horizontal diffusion COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 18

B. Convective case with COSMO-1 Time series of Max. vertical wind Max. horizontal wind

B. Convective case with COSMO-1 Time series of Max. vertical wind Max. horizontal wind With horizontal diffusion NO horizontal diffusion (hd) COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss NO hd but with UB modif. advection Guy de Morsier 19

B. Convective case 29 May 2010 24 h forecast (u, v, w) from 6

B. Convective case 29 May 2010 24 h forecast (u, v, w) from 6 to 10 km height COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 20

Summary • Choice of the orographic filtering is not too bad considering the spectral

Summary • Choice of the orographic filtering is not too bad considering the spectral evaluation but depends on the model dynamics • Stable run can produce meaningless values (horizontal wind) at some particular time • Possible to run cases without horizontal diffusion • The advection scheme has an impact on the results ( more tests needed!) COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 21

Future • Set up an assimilation cycle for COSMO-1 • Regular runs from the

Future • Set up an assimilation cycle for COSMO-1 • Regular runs from the assimilation cycle • Evaluate against COSMO-2 • Need more test cases and/or case studies: - Convection - Stratus - Strong precipitation - Föhn COSMO-GM, Roma / Sept. 2011 / Status of the COSMO-1 configuration at Meteo. Swiss Guy de Morsier 22