The latest version of WRF (3.6) provides both GHI and DNI...

Thanks, GHI and DNI parameters can we get from WRF-NMM or WRF-ARW or both?

See http://www2.mmm.ucar.edu/wrf/users/wrfv3.6/updates-3.6.html

Thanks Chris, I will check.

Hi Chris,

I installed wrf-arw v3.6 and run the model for 1 day for checking the required output parameters swddir, swddni and swddif, but the parameters are not existed in wrfout file. i enabled swint_opt=1 also. still i need to make any changes to get the above paramters?.

my namelist.input:

&time_control

run_days = 1,

run_hours = 0,

run_minutes = 0,

run_seconds = 0,

start_year = 2013, 2000, 2000,

start_month = 01, 01, 01,

start_day = 01, 24, 24,

start_hour = 00, 12, 12,

start_minute = 00, 00, 00,

start_second = 00, 00, 00,

end_year = 2013, 2000, 2000,

end_month = 01, 01, 01,

end_day = 02, 25, 25,

end_hour = 00, 12, 12,

end_minute = 00, 00, 00,

end_second = 00, 00, 00,

interval_seconds = 21600

input_from_file = .true.,.true.,.true.,

history_interval = 180, 60, 60,

frames_per_outfile = 1000, 1000, 1000,

restart = .false.,

restart_interval = 5000,

io_form_history = 2

io_form_restart = 2

io_form_input = 2

io_form_boundary = 2

debug_level = 0

/

&domains

time_step = 17,

time_step_fract_num = 0,

time_step_fract_den = 1,

max_dom = 1,

e_we = 50, 112, 94,

e_sn = 50, 97, 91,

e_vert = 30, 30, 30,

p_top_requested = 5000,

num_metgrid_levels = 38,

num_metgrid_soil_levels = 4,

dx = 5600, 10000, 3333.33,

dy = 5600, 10000, 3333.33,

grid_id = 1, 2, 3,

parent_id = 0, 1, 2,

i_parent_start = 1, 31, 30,

j_parent_start = 1, 17, 30,

parent_grid_ratio = 1, 3, 3,

parent_time_step_ratio = 1, 3, 3,

feedback = 1,

smooth_option = 0

/

&physics

mp_physics = 3, 3, 3,

ra_lw_physics = 1, 1, 1,

ra_sw_physics = 1, 1, 1,

radt = 30, 30, 30,

sf_sfclay_physics = 1, 1, 1,

sf_surface_physics = 2, 2, 2,

bl_pbl_physics = 1, 1, 1,

bldt = 0, 0, 0,

swint_opt = 1,

cu_physics = 1, 1, 0,

cudt = 5, 5, 5,

isfflx = 1,

ifsnow = 1,

icloud = 1,

surface_input_source = 1,

num_soil_layers = 4,

sf_urban_physics = 0, 0, 0,

/

&fdda

/

&dynamics

w_damping = 0,

diff_opt = 1, 1, 1,

km_opt = 4, 4, 4,

diff_6th_opt = 0, 0, 0,

diff_6th_factor = 0.12, 0.12, 0.12,

base_temp = 290.

damp_opt = 0,

zdamp = 5000., 5000., 5000.,

dampcoef = 0.2, 0.2, 0.2

khdif = 0, 0, 0,

kvdif = 0, 0, 0,

non_hydrostatic = .true., .true., .true.,

moist_adv_opt = 1, 1, 1,

scalar_adv_opt = 1, 1, 1,

/

&bdy_control

spec_bdy_width = 5,

spec_zone = 1,

relax_zone = 4,

specified = .true., .false.,.false.,

nested = .false., .true., .true.,

/

&grib2

/

&namelist_quilt

nio_tasks_per_group = 0,

nio_groups = 1,

/

Waiting for your reply,

Thanks & regards,

Malleswararao M

I privately asked the developer of the new DNI/DIF algorithm in WRF to help you directly: https://www.researchgate.net/profile/Jose_Ruiz-Arias?_sg=ewwZCWKqay8ECxDhl7yb9U0zUyyrupXU6%2F4qcJWZqN6bL%2BSZVrdPSUoa0%2FHXTE4z_Yvxna66g%2BJQX8QQ21zVMSpzpbZGVROv98CsfD2N7w7X8x41Vq2T%2FMwHCItl6IEgI

Thank you Sir, but i did not get any information from the link you sent.

By default, WRFv3.6 does not save swddir, swddni and swddif in the wrfout file. To save them, edit the file Registry/Registry.EM_COMMON and search for the lines that start with "state real swddir", "state real swddni" and "state real swddif". Change the 8-th column of these lines from "rd" to "rhd" and save the file. Then you have to recompile the code as usual. However, you should make sure you clean the code before the re-compilation. That is, from the root directory of the WRF' source code:

./clean -a

./configure

./compile em_real.

Hope this helps

Thanks Joes and i will try, let you know the feedback. I have one more question, whether we can get these parameters from WRF-NMM model?

I don't really know whether WRF's people moved also this new code to de NMM branch. I did all the devel on the WRF-ARW code.

Thanks Jose, Its working fine with WRF-ARW. I extracted all the three parameters. Is there any linear relationship between SWDDIR, SWDDIF and SWDDNI for quantitative checking?. Out of three, which parameter denotes GHI and which one denotes DNI?

Waiting for your reply,

Thanks & Regards,

Malleswararao M

SWDOWN is GHI; SWDDNI is DNI; SWDDIR is direct irradiance over the horizontal surface; and SWDDIF is diffuse irradiance.

As usual, SWDOWN=SWDDIR+SWDDIF

And swddni = swddir/cos(z)

Thanks Jose and Chris for immediate reply, It helps me a lot for my work.

SWDOWN=SWDDIR+SWDDIF equation satisfied with my output , in 2nd equation, there is a small variation in calculating swddni, swddni = swddir/cos(z).

The variation may be due to the method you use to compute cos(z). If you want, you can edit again the Registry to get cos(z) directly in the wrfout. Just look for the variable COSZEN, add a "h" in the 8-th column, save and recompile as I already told you. Then you should get cos(z) as COSZEN in the wrfout.

It is already enabled in my registry, and i extracted COSZEN directly from wrfout file and checked it. i added excel sheet, you can observe the difference. If you need swddir,swddni and coszen files, i can forward you.

You shouldn't get so high difference! Double check your namelist. Are you using by chance the swint_opt? Don't use it. Also review your set up for model time step (time_step), radiation time step (radt) and saving time step (time_history). Make sure everything is coherent.

Hi Jose,

Thank you, I used swint_opt=1 in my namelist.input, time_step=17, radt=30, time_history means history_interval=180,.

Now i changed my namelist.input as without swint_opt, radt=30, time_step=17 and history_interval=60, now model is running and let you know the result.

how can we put time_step, radt and history_interval in coherent manner, is there any relation?

Thanks & Regards,

Hi Jose,

Thanks, Now the two equations are satisfied after removing swint_opt=1.

I attached the excel sheet here for the same.