Usage of the newly added SMS-3DTKE PBL

Topics/questions specifically related to WRF model physics
Post Reply
sekluzia
Posts: 187
Joined: Mon Oct 15, 2018 12:42 pm

Usage of the newly added SMS-3DTKE PBL

Post by sekluzia » Thu Jun 11, 2020 1:16 pm

Dear Colleges,

Would you recommend to use the recently added (in the WRF V4.2) three dimensional scale-adaptive TKE subgrid mixing parameterization scheme (SMS-3DTKE, km_opt=5) for my all domains with spatial resolution ranging from 9 km (d01) to 333 m (d04)?

Kind regards,
Artur

kwerner
Posts: 2287
Joined: Wed Feb 14, 2018 9:21 pm

Re: Usage of the newly added SMS-3DTKE PBL

Post by kwerner » Fri Jun 12, 2020 6:53 pm

Artur,
Yes, you can use it for all domains. It's meant to be used in the LES, mesoscale, and gray-zone.
NCAR/MMM

sekluzia
Posts: 187
Joined: Mon Oct 15, 2018 12:42 pm

Re: Usage of the newly added SMS-3DTKE PBL

Post by sekluzia » Sat Jun 13, 2020 10:42 am

Thanks a lot!

vanitas456
Posts: 3
Joined: Tue Mar 23, 2021 8:36 am

Re: Usage of the newly added SMS-3DTKE PBL

Post by vanitas456 » Tue Mar 23, 2021 8:55 am

Hi,
I have some question about how to use the SMS-3D-TKE (3DTKE) scheme.

My supervisor suggest me to do some files modification before i can use the 3DTKE scheme.
Could you tell me which files did i have to modify before i can use the 3DTKE scheme? or maybe i just simply need to do bl_pbl_physics = 0, diff_opt = 2, and km_opt = 5 in the namelist.input.

Best,
Rahman

kwerner
Posts: 2287
Joined: Wed Feb 14, 2018 9:21 pm

Re: Usage of the newly added SMS-3DTKE PBL

Post by kwerner » Tue Mar 23, 2021 8:45 pm

Rahman,
If you haven't already, I would suggest following the information given in these slides. Let us know if you have additional questions.
NCAR/MMM

Ming Chen
Posts: 1456
Joined: Mon Apr 23, 2018 9:42 pm

Re: Usage of the newly added SMS-3DTKE PBL

Post by Ming Chen » Mon Mar 29, 2021 5:02 pm

SMS-3DTKE is a scale-aware PBL scheme, which is especially useful for nest cases with large differences in grid size between domains. You are right that to implement this scheme, you need to set bl_pbl_physics = 0, diff_opt = 2, and km_opt = 5.
Since this is a relatively new feature in WRF, we will appreciate if you can post results using this scheme, especially its performance compared to other 'old' PBL schemes. Thanks in advance.
WRF Help Desk

vanitas456
Posts: 3
Joined: Tue Mar 23, 2021 8:36 am

Re: Usage of the newly added SMS-3DTKE PBL

Post by vanitas456 » Wed Mar 31, 2021 11:15 pm

Thank you very much for the answers!

alainF
Posts: 37
Joined: Fri Apr 19, 2019 8:12 am

Re: Usage of the newly added SMS-3DTKE PBL

Post by alainF » Fri Apr 02, 2021 10:01 am

Hello everybody,
I have a question related to this topic :
If I set bl_pbl_physics = 0, what will happen for cumulus scheme and coarse grid size such as 25 km ? In a multi-nest simulation the parent nest can have such a large grid size. Can I still use a cumulus physics or shall I set cu_physics = 0 for ALL domains.

Thank you

Ming Chen
Posts: 1456
Joined: Mon Apr 23, 2018 9:42 pm

Re: Usage of the newly added SMS-3DTKE PBL

Post by Ming Chen » Mon Apr 05, 2021 9:39 pm

The SMS-3DTKE scheme will treat the PBL process at coarse resolution (such as 25km) in a way more similar to traditional PBL scheme. When the grid interval becomes smaller, this scheme gradually transfer to LES mode.
cumuls parameterization must be turned on for grid intervals larger than 10km, and it can be on or off for the grey zone (4-10km), and it should be off for grid intervals smaller than 3km. It does't have to be the same for all domains.
WRF Help Desk

alainF
Posts: 37
Joined: Fri Apr 19, 2019 8:12 am

Re: Usage of the newly added SMS-3DTKE PBL

Post by alainF » Sat Apr 10, 2021 8:17 am

Thank you for your answer. I have just read it.
In doubt, I kept cumulus parametrization for the coarse grid domain (25 km), for the 5 km grid size, and switched it off for the fine grid domain (1km). The results seem realistic in terms of temperature, cloud and precipitation.

Ming Chen
Posts: 1456
Joined: Mon Apr 23, 2018 9:42 pm

Re: Usage of the newly added SMS-3DTKE PBL

Post by Ming Chen » Mon Apr 12, 2021 5:15 pm

Thanks for the update.
WRF Help Desk

Post Reply

Return to “WRF Physics”