What is the equation and program for calculating vertical velocity in WRF?

[mirabelle]

Hello, I am using WRF version 3.7.1.
I want to calculate the vertical velocity equation by this equation.
Could you please tell me if this is consistent with the equations used in WRF?
Which subroutine calculates each term?
Is it possible to directly output these sub-variables in wrfout?

 

[kwerner]

Hi,
Take a look at the WRF Technical Note, which includes all the equations used in the model. I would then recommend looking at the Registry/Registry.EM_COMMON file and searching for some of the key words in your terms to find the correct variable name. You can then search the code to find where that variable is used. You will likely notice that they are calculated in multiple files/subroutines, so you'll want to match the file to the schemes you're using (e.g., physics routines that may calculate these).

If the variables are not already being output, there are a couple methods you can use to output them. Take a look at this section of the WRF Users' Guide.

 

[mirabelle]

Hi,
Take a look at the WRF Technical Note, which includes all the equations used in the model. I would then recommend looking at the Registry/Registry.EM_COMMON file and searching for some of the key words in your terms to find the correct variable name. You can then search the code to find where that variable is used. You will likely notice that they are calculated in multiple files/subroutines, so you'll want to match the file to the schemes you're using (e.g., physics routines that may calculate these).

If the variables are not already being output, there are a couple methods you can use to output them. Take a look at this section of the WRF Users' Guide.

Thanks for your kind reply. I realized that calculate w need several variables. But I can not find this from wrfout or Registry.EM_COMMON file:
ρ（density of the dry air）
Fw ( forcing terms arising from model spherical projections)
μd0 and μ (Basic state and perturbation of the mass of a dry air column)
can you tell me how to get these variable?

 

[kwerner]

I believe the variable for the density of dry air is "RHO."

Base state of the mass of dry air is "mub," and the perturbation is "mu."

I'm not sure about the spherical forcing terms. I'll ask someone who may know and get back to you about that one.

 

[mirabelle]

I believe the variable for the density of dry air is "RHO."

Base state of the mass of dry air is "mub," and the perturbation is "mu."

I'm not sure about the spherical forcing terms. I'll ask someone who may know and get back to you about that one.

Thank you.
I have another question.
I want to calculate the buoyancy term g*ude/ud, where μd=μd0+μde， μd0 is the base dry air column, and μde is the perturbation.
This calculation should be performed in 3D dimensions, but mu and mub are 2D variables.
How can I convert mu and mub into 3D variables?

 

[kwerner]

I've heard back from my colleague, who suggested for the spherical forcing terms, you should look at the map factors and curvature terms in the Tech Note. As for converting variables to 3d terms, try taking a look at some of the existing 3d terms, and look in the code to see how they are calculated.