Calculation about theta tendency

[wrf_fanatic]

Dear Sir or Madam,
I checked Registry.EM_COMMOM file and found that there are some variables about potential temperature. They are: h_diabatic, RTHFTEN, RTHRATEN, RTHCUTEN, RTHSHTEN, RTHBLTEN.

'H_diabatic' is described as 'MICROPHYSICS LATENT HEATING' while others are described as 'THETA TENDENCY DUE TO XX SCHEME'. Their units are all 'K/s'.

If i want to calculate local potential temperature tendency, is it correct to add up all these variables straightly without extra process? I am concerned about that there might be extra calculation especially the 'h_diabatic', which is described differently with the others.

I also found that RTHFTEN, which is 'TOTAL ADVECTIVE POTENTIAL TEMPERATURE TENDENCY', is zero at all grid points at all time steps.

It would be nice if you could offer me some suggestion!

Thank you!

 

[Ming Chen]

Hi,
Please see my answers below:

(1) If i want to calculate local potential temperature tendency, is it correct to add up all these variables straightly without extra process? I am concerned about that there might be extra calculation especially the 'h_diabatic', which is described differently with the others.

It is correct that you need to add these tendencies. RTHFTEN is a small term of advective temperature tendency, which you should also include

(2) I also found that RTHFTEN, which is 'TOTAL ADVECTIVE POTENTIAL TEMPERATURE TENDENCY', is zero at all grid points at all time steps.
RTHFTEN is only available for certain cumulus scheme. You need to go to module_big_step_utilities_em.F to remove the if test for cumulus schemes
or activate one of those schemes to have this array.