Lightning flash counts are coming zero

[Subhojit Ghosal Chowdhury]

Dear all,

               I am trying to simulate a lightning event using WRF-4.2.1 with fast sbm micro physics scheme. While the same set up was working well for WRF-3.8.1, but here in new version CG & IC lightning flashes are always coming zero. I have attached used name list here. I will be highly obliged if you can help regarding this matter.

Regards

Subhojit

[Mary Barth]

Hello Subhojit,

I looked at your namelist.input file and would like to offer a few
suggestions.

I see you are running 2 domains, one at dx=10km and one at dx=2km. Since
the outer domain requires a cumulus parameterization scheme, it is best
to use lightning_option 11 for the outer domain.

I see that the time_step = 30 seconds and the lightning_dt = 5 seconds.
I suggest changing lightning_dt to either 30 seconds or 60 seconds.

Be sure that cellcount_method is set for the inner domain (check the
namelist.output file). It looks like you chose the default but the WRF
and WRF-chem user guide does not say which option is the default. It
appears that you have large domains in which many storms could occur. I
recommend using the cellcount_method = 1.

- Mary

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Mary Barth Phone: 303-497-8186
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National Center for Atmospheric Research
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[Mary Barth]

Hi Subhojit,

I suggest setting the debug_level=100 and look at the rsl.out file where you would expect to have lightning.

I looked at differences in the lightning driver routine between WRFV3 and WRFV4 and there are some. I didn't make these changes so I'm not as familiar with them. It would be good to check how the model is going through on the checks (if lightning_option..., for example). There's also one bit of code I'm not sure about and will ask the WRF folks in MMM about it.

Cheers,
Mary

On 8/26/22 4:05 AM, Subhojit Ghosal Chowdhury wrote:

Hello Mary, I have changed the name list according to your suggestions. Though CG & IC flash count values are coming for domain1, still zero for domain 2. Can you suggest, what modifications are needed now? I have attached the name list here. 

Regards

Subhojit

On Thu, Aug 25, 2022 at 2:11 PM Subhojit Ghosal Chowdhury <ghosals...@gmail.com> wrote:

Thank you for the suggestions Mary. I will implement these.

Regards

Subhojt

--

Subhojit Ghoshal Chowdhury

Ph.D Scholar

Centre for Atmospheric Sciences 

Indian Institute of Technology Delhi

--

Subhojit Ghoshal Chowdhury

Ph.D Scholar

Centre for Atmospheric Sciences 

Indian Institute of Technology Delhi

[Subhojit Ghosal Chowdhury]

Hello Mary, I have changed the name list according to your suggestions. Though CG & IC flash count values are coming for domain1, still zero for domain 2. Can you suggest, what modifications are needed now? I have attached the name list here. 

Regards

Subhojit

On Thu, Aug 25, 2022 at 2:11 PM Subhojit Ghosal Chowdhury <ghosals...@gmail.com> wrote:

Thank you for the suggestions Mary. I will implement these.

Regards

Subhojt

On Thu, Aug 25, 2022 at 3:58 AM Mary Barth <bar...@ucar.edu> wrote:

--

Subhojit Ghoshal Chowdhury

Ph.D Scholar

Centre for Atmospheric Sciences 

Indian Institute of Technology Delhi

[Subhojit Ghosal Chowdhury]

Thank you for the suggestions Mary. I will implement these.

Regards

Subhojt

On Thu, Aug 25, 2022 at 3:58 AM Mary Barth <bar...@ucar.edu> wrote: