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Obtain sunshine hours and RH using wrf

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rajitha_AIT

New member
Hello. Im a new user to WRF for climate variables

I was able to find out that the WRF V4.0 can output useful climate variables such as Min, Max, and Mean T2 as well as Rainfall flux using wrfxtrm stream. However, I am still unable to figure out how to obtain sunshine hours (Hours of SWDOWN > 120 W m-2) and RH.

I am aware that previous versions (prior to WRF V3.6) had to be compiled with clWRF to obtain these variables with clwrf_sunshine as given below.

output_diagnostics = 1 ! Activates extreme values computation (0; deactivates [default])
clwrf_sunshine = 1 ! Activates sunshine computation (0; deactivates [default])
clwrf_gust_wind = 1 ! Activates gust wind computation (0; deactivates [default])
clwrf_accum_precip = 1 ! Activates accumulated precipitation computation (0; deactivates [default])
clwrf_ts_pbl = 1 ! Activates additional time-series variables (0; deactivates [default])
timesteps1_movaccum = 13 ! Number of time steps +1 for the time-moving accumulation of precipitation (example for a DT=150; moving accumulations of 30 minutes)
fixtimeaccum = 3600 ! Time of the fixed precipitation accumulation in seconds (1 hour)

I am still trying to figure out how to get the same variables using WRF V4.0. Any hints or suggestions would be highly appreciated. :)

Thanks in advance.
 
Hi,
This inquiry has been moved to the "Special Running Options" section of the forum. Someone will get to your question soon.
 
Hi,
To get RH, you can use the pressure level diagnostic output option: https://www2.mmm.ucar.edu/wrf/users/docs/user_guide_v4/v4.1/users_guide_chap5.html#output_diags

As for sunshine hours, unfortunately that is not a built-in option, but you could probably write some code to ask it to output those values, perhaps giving it a different variable name, or only having the values above the particular threshold print out.
 
Hi

Thanks a lot for the prompt reply. I will try the suggestion you recommended for computing RH. Also for obtaining sunshine hours, I guess WRF-CORDEX is an option which I have tried successfully.

Wondering why sunshine hour diagnostic which was available in previous WRF versions under clWRF was removed completely. :(

Anyways, thanks again for your reply. Hope others will be also benefited by this information. In conclusion:

'WRFV4 cannot output sunshine hours as an inherent output by the model itself. Best option so far is to try WRF-CORDEX which is available for WRFV4.0'

Cheers
Rajitha
 
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