how to set up and run wrf model. outline n how to download and compile the wrf code? n namelist n...

How to set up and run WRF model

Outline

How to download and compile the WRF code? Namelist Input and output files

How to download and compile WRF?

Download WRF source code from

http://www.wrf-model.org/users/download.html What you get is

WRFV1.TAR.gz After gunzip and untar the file, you should see a

directory WRFV1 cd to WRFV1 directory, and you should see ..

WRFV1 directory

CHANGES

Makefile

README

README_test_cases

Registry/

arch/

clean

compile

configure

dyn_eh/

External/frame/inc/main/phys/run/share/test/tool/

Type ‘configure’ to create configure.wrf file for your particular machine:

azalea2:/mmmtmp/wrfhelp/WRFV1>configurechecking for perl5... nochecking for perl... found /usr/local/bin/perl (perl)Will use NETCDF in dir: /usr/local/netcdf-------------------------------------------------------Please select from among the following supported

platforms.

1. Compaq OSF1 alpha (single-threaded) 2. Compaq OSF1 alpha SM (OpenMP) 3. Compaq OSF1 alpha DM/SM (RSL, MPICH, RSL IO,

OpenMP) 4. Compaq OSF1 alpha DM/SM (RSL, DECMPI, RSL IO,

OpenMP)

Enter selection [1-4] : 1

You’ll see:You have chosen: Compaq OSF1 alpha (single-threaded)These are the default options for this platform:--------------------------------------------------------------#OMP = OMPCPP = FC = f90CC = ccCFLAGS =FCOPTIM = -fast -O4 -inline all……--------------------------------------------------------------These will be written to the file configure.wrf here in the top-leveldirectory. If you wish to change settings, please edit that file.If you wish to change the default options, edit the file: arch/configure.defaults

Configuration successful. To build the model type compile .

After one obtains the configure.wrf file, type

compile eh_real

to compile

If compile is successful, you should have two executables built in directory main/:

real.exe

wrf.exe

And these executables are linked to ./test/eh_real/

test/eh_real directory

These are what one’d see in test/eh_real/ directory:

LANDUSE.TBL

RRTM_DATA

namelist.input

real.exe -> ../../main/real.exe

wrf.exe -> ../../main/wrf.exe

Before you run real and wrf, edit the namelist for runtime options

&namelist_01 time_step_max = 1, number of time steps to run max_dom = 1, number of domains (leave as is) dyn_opt = 3, dynamics option: 1 = leapfrog, not yet implemented 2 = Runge-Kutta 2nd order 3 = Runge-Kutta 3rd order

diff_opt = 1, diffusion option: 1 = old diffusion scheme (uses khdiv,kvdif) 2 = new diffusion scheme (uses km_opt) (stress form) km_opt = 1, eddy coefficient option 1 = constant (from khdiv kvdif) 2 = 1.5 order TKE closure 3 = Smagorinsky first order closure damp_opt = 1, upper level damping flag 0 = without damping 1 = with damping

Description of namelist_01

ISFFLX = 1, heat and moisture fluxes from the surface 1 = with fluxes from the surface 0 = no flux from the surface

IFSNOW = 0, snow-cover effects 1 = with snow-cover effect 0 = without snow-cover effect

ICLOUD = 1, cloud effect to the optical depth in radiation 1 = with cloud effect

0 = without cloud effect

Description of namelist_01

num_soil_layers = 5, number of soil layers in land surface model

spec_bdy_width= 5, number of rows for specified boundary value nudging

spec_zone = 1, number of points in specified zone (spec b.c. option)

relax_zone= 4, number of points in relaxation zone (spec b.c. option)

tile_sz_x = 0, number of points in tile x direction

tile_sz_y = 0, number of points in tile y direction

numtiles= 1, number of tiles per patch (alternative to above two)

debug_level = 0/ 50,100,200,300 values give increasing prints

Description of namelist_01

&namelist_02

grid_id = 1, domain identifier

level = 1, domain nest level

s_we = 1, start index in x (west-east) direction

e_we = 32, end index in x (west-east) direction

s_sn = 1, start index in y (south-north) direction

e_sn = 32, end index in y (south-north) direction

s_vert = 1, start index in z (vertical) direction

e_sn = 31, end index in z (vertical) direction

Description of namelist_02

Description of namelist_02

time_step_count_output = 10, history output frequency in timesteps

frames_per_outfile = 10, output times per history file

time_step_count_restart = 10, restart output frequency in timesteps

time_step_begin_restart = 0, timestep for restart run to begin

0=not a restart

time_step_sound =4, number of sound steps per timestep

&namelist_03

dx = 200, grid length in x direction

dy = 200, grid length in y direction

dt = 2., time-step for advection

ztop = 20000., the height of the model top

zdamp = 5000., damping depth from model top

dampcoef = 0.2, damping coefficient (dampcoef <= 0.25)

smdiv = 0, divergence damping (0.1 is typical)

epssm = .1, time off-centering for vertical sound waves

khdif = 0, horizontal diffusion constant (m^2/s)

kvdif = 0, vertical diffusion constant (m^2/s)

mix_cr_len = 200, the critical value of the mixing length for

isotropic and anisotropic diffusion

Description of namelist_03

radt = 0, minutes between radiation physics calls

bldt = 0, minutes between boundary-layer physics calls

cudt = 0, minutes between cumulus physics calls

julyr = 0, Julian Year for model start

julday = 1, Julian Day for model start

gmt = 0./ GMT time for model start

Description of namelist_03

&namelist_04

periodic_x = .false., periodic boundary conditions in x direction

symmetric_xs = .false., symmetric boundary conditions at x start (west)

symmetric_xe = .false., symmetric boundary conditions at x end (east)

open_xs = .false., open boundary conditions at x start (west)

open_xe = .false., open boundary conditions at x end (east)

periodic_y = .false., periodic boundary conditions in y direction

symmetric_ys = .false., symmetric boundary conditions at y start (south)

symmetric_ye = .false., symmetric boundary conditions at y end (north)

open_ys = .false., open boundary conditions at y start (south)

open_ye = .false., open boundary conditions at y end (north)

nested = .false., nested boundary conditions (inactive)

specified = .false., specified boundary conditions (inactive)

top_radiation= .false., upper radiative boundary conditions (inactive)

Description of namelist_04

chem_opt = 0, chemistry option

mp_physics microphysics option

= 0, no microphysics

= 1, Kessler scheme

= 2, Lin et al. scheme

= 3, NCEP 3-class simple ice scheme

= 4, NCEP 5-class scheme

ra_lw_physics longwave radiation option

= 0, no longwave radiation

= 1, rrtm scheme

ra_sw_physics shortwave radiation option

= 0, no shortwave radiation

= 1, Dudhia scheme

= 2, Goddard short wave

Description of namelist_04

bl_sfclay_physics surface-layer option

= 0, no surface-layer

= 1, Monin-Obukhov scheme

bl_surface_physics land-surface option

= 0, no land-surface

= 1, thermal diffusion scheme

bl_pbl_physics boundary-layer option

= 0, no boundary-layer

= 1, mrf scheme

cu_physics cumulus option

= 0, no cumulus

= 1, Kain-Fritsch scheme

= 2, Betts-Miller-Janjic scheme 

Description of namelist_04

h_mom_adv_order = 5, horizontal momentum advection order (5=5th, etc.)

v_mom_adv_order= 3, vertical momentum advection order

h_sca_adv_order= 5, horizontal scalar advection order

v_sca_adv_order= 3, vertical scalar advection order 

io_form = 1, (not active)

= 2, NetCDF format

Description of namelist_04

&namelist_05  

start_year = 2000, four digit year of starting time

start_month= 11, two digit (01-12) month of starting time

start_day = 20, two digit (01-31) day of starting time

start_hour = 12, two digit (00-23) hour of starting time

start_minute= 00, two digit (00-59) minute of starting time

start_second= 00, two digit (00-59) second of starting time 

end_year = 2000, four digit year of ending time

end_month = 11, two digit (01-12) month of ending time 

end_day = 21, two digit (01-31) day of ending time

 end_hour = 00, two digit (00-23) hour of ending time

end_minute = 00, two digit (00-59) minute of ending time 

end_second = 00, two digit (00-59) second of ending time

interval_seconds= 43200, time interval in seconds between analysis (and boundary) times

Description of namelist_05

real_data_init_type which type of real input:

= 1, WRF SI

= 2, MM5

= 3, user written routine read_generic in module_si_io.F

Description of namelist_05

WRF input files

Running real.exe turns

wrf_input.d01.yyyy-mm-dd_hh:mm:ss

to

wrfinput and wrfbdy

WRF output files

After one runs wrf.exe, WRf produces these output files:

wrfout_01_000000: history file

wrfrst_01_nnnnnn: restart file where nnnnnn is model time step

If one splits output files, one may obtain:

wrfout_01_xxxxxx

where xxxxxx is the time step at which the output file is written.