Running the COSMO-Model

Transcription

1 Running the COSMO-Model Ulrich Schättler, Ulrich Blahak, Alberto de Lozar Deutscher Wetterdienst BU Research and Development Department for Numerical Modelling

2 Up to now Up to now you know how to use the run-scripts and start a job You can prepare the initial and boundary data for a run of the COSMO- Model 2

3 Coming up next Now you will try to modify the Namelist Input for the COSMO-Model Chapter 3 of the Tutorial explains some of the most important Namelist variables and gives some background LMGRID: The Model Domain RUNCTL: Parameters to control the run of the COSMO-Model DYNCTL: Settings for the dynamics PHYCTL: DIACTL: Settings for the physical parameterizations Settings for the diagnostics IOCTL, GRIBIN, GRIBOUT: Settings for I/O The cosmo_170323_5.04e-directory contains two examples of run-scripts run_cosmo_eu: for 7 km applications run_cosmo_de: for higher resolutions (about 2-3 km) 3

4 Specifying the Directories and other Stuff You have to set the script variables at the beginning: NPX=10, NPY=12 depending on the domain size DATE= start date of the forecast FORM=api2 the format of the output BASE=/e/uwork/trngxyz/ for example INIDIR=$BASE/COSMO_7_input BD_DIR=$BASE/COSMO_7_input OBSDIR not needed OUTPUT=$BASE/COSMO_7_output RESTAR not needed 4

5 Specifying the Domain: /LMGRID/ You have to set the same variables as in the INT2LM group /LMGRID/ startlat_tot, startlon_tot: coordinates of the lower left grid point in rotated (!) coordinates pollat, pollon: geographical coordinates of the rotated North Pole dlon, dlat: resolution ( ~ 7 km; ~ 2.8 km) ie_tot, je_tot, ke_tot: size of the model grid in grid points And the values have to be exactly the same as in INT2LM! 5

6 Parameters to Control the Run: /RUNCTL/ Date and range of simulation: ydate_ini, hstart, hstop, Time step, number of boundary lines, dt=66: for Runge-Kutta and resolution of degrees nboundlines=3: for Runge-Kutta number of processors (set by script variable NPX, NPY): 10x12 or 10x24 Choose components you want to run lphys physical parameterizations ldiagnos diagnostics luseobs assimilation luse_rttov synthetic satellite images lartif_data artificial (idealized) test runs 6

7 Settings for the Dynamics: /DYNCTL/ Select dynamical core: l2tls=.true. (Runge-Kutta) or.false. (Leapfrog) The next variables are only for the Runge-Kutta dynamical core: irunge_kutta = 1 irk_order = 3 iadv_order = 3 (5 for higher resolution) y_scalar_advect = BOTT2_STRANG itype_fast_waves = 2 rlwidth = 85000: the width of the relaxation layer should extend about grid points. A rule of thumb is: resolution in meters * # grid points There are more namelist variables for the dynamics. See the Tutorial for some more and the COSMO User Guide for a complete list of variables. 7

8 Settings for the Physics: /PHYCTL/ For every parameterization is a logical switch to turn it on / off: lgsp, lrad, ltur, lconv, lsoil, llake, lseaice, lsso Note that llake has to be.false. for the cases you run during the exercises. Every parameterization then has some more variables for fine-tuning itype_gscp, itype_conv: to choose a special variant See the COSMO User Guide for a complete list of variables. 8

9 Settings for the I/O Basic settings: /IOCTL/ lbdclim ngribout yform_read= apix Settings for input of data /GRIBIN/ ydirini, ydirbd: hincbound=3 lchkini, lchkbd: to choose the climate mode number of output blocks (see below) format to read data set by script variables increment of boundaries if.true., write ASCII file YUCHKDAT lan_xxx=.true.: to choose whether a variable is taken from the INT2LM (or an external analysis) (.TRUE.) or from a data assimilation cycle (.FALSE.) If this setting is wrong it might result in an error message: Not all variables / levels could be read 9

10 Settings for the I/O (II) Settings for output /GRIBOUT/: there can be more than one group hcomb = 0.0,78.0,1.0 start, stop, increment for writing results ydir set by script variable yform_write= grb1 ( api2, ncdf ) 10

11 Settings for the Diagnostics: /DIACTL/ To produce some diagnostic (ASCII) output for a quick monitoring of the forecast: nomeanval, nincmeanval: print some mean values to YUPRMASS, YUPRHUMI lgplong, lgpshort n0gp=0, hincgp=1.0 to produce meteograph output (M_* files) stationlist_tot = 0, 0, 46.7, 6.2, RODGAU, 53, 59, 0.0, 0.0, MY_STATION 11

12 Now try to run the COSMO- Model for your specified area 12

13 Thank you very much for your attention 13