CLD3 - already available in WRF Solar EPS?

[and_hoc]

As I am currently running WRF Solar EPS with the newest WRF v4.4, I was wondering, if it is possible to already use the CLD3 option in this version. On the WRF Solar EPS website it is already listed, as well as mentioned in the Final Report on Probabilistic Cloud Optimized Day-Ahead Forecasting
System Based on WRF-Solar (https://www.nrel.gov/docs/fy22osti/81904.pdf).

In the release notes I found the following statement: " [...] An Update to this, plus the cloud-fraction scheme 'icloud = 3' to better match observations." But 'icloud = 3' is not compatible with the Deng shallow cumulus convection sheme. So I was wondering, is this even the mentioned CLD3 option? And if so, what would be the recommended namelist setting in order to use it?

 

[jimenez]

yes, you can. These are the options related to that scheme:
pert_cld3 = .false. ! Activates perturbations to clouds generated with icloud = 3
pert_cld3_qv = 0.0
pert_cld3_t = 0.0

so you can set pert_cld3 = .true. and pert_cld3_qv and pert_cld3_t = 1.0

Remember that to activate WRF-Solar EPS you need to set
multi_perturb = 1

And if adding the perturbations hurts performance you can modify the default spdt entry:
spdt = -1.0 ! Frequency to update the stochastic perturbations [minutes]. A negative value indicates for every time step

Also set the entry nens to a different value for each ensemble member since this number controls the random number generation.

All these options go into the stoch block of the WRF namelist

See the README.namelist file in the run directory for a complete list of the namelist settings related to WRF-Solar EPS
Pedro.

 

[and_hoc]

Thanks! That actually helps a lot!

 

[viviq18]

yes, you can. These are the options related to that scheme:
pert_cld3 = .false. ! Activates perturbations to clouds generated with icloud = 3
pert_cld3_qv = 0.0
pert_cld3_t = 0.0

so you can set pert_cld3 = .true. and pert_cld3_qv and pert_cld3_t = 1.0

Remember that to activate WRF-Solar EPS you need to set
multi_perturb = 1

And if adding the perturbations hurts performance you can modify the default spdt entry:
spdt = -1.0 ! Frequency to update the stochastic perturbations [minutes]. A negative value indicates for every time step

Also set the entry nens to a different value for each ensemble member since this number controls the random number generation.

All these options go into the stoch block of the WRF namelist

See the README.namelist file in the run directory for a complete list of the namelist settings related to WRF-Solar EPS
Pedro.

hi
I'm sorry to bother you, I'm a newbie. I want to know if the nens option has to be changed ten times if I want to generate 10 ensemble members.Again, I am equally interested in what the difference between what nens=1 or 10 means.Looking forward to your reply！