#### Yuting_Deng

##### New member

Recently I have some questions adding variables to the fast_sbm file, the density (rho_phy) unit in this file is [kg m-3], and rhocgs unit should be [g m-3] because there is a statement 'rhocgs(I,K,J)=rho_phy(I,K,J)*0.001' in this file.

Now the problems are coming, an example: QG(I,K,J)=QG(I,K,J)+(1./RHOCGS(I,K,J))*COL*chem_new(I,K,J,KR)*XG(KRR)*XG(KRR)*3, I extrapolate from the entire file that the chen_new's unit is [g-1 cm-3], XG's unit is g, and the unit of QG is [kg kg-1], if the unit of rhocgs is [g cm-3] then the resulting unit correspond.

However, the next statement "QNG(I,K,J)=QNG(I,K,J)+COL*chen_new(I,K,J,KR)*XG(KRR)*3/rhocgs(I,K,J)*1000", the unit of QNG is [kg-1,] now we still assume that the unit of rhocgs is [g cm-3], if we want to do that, it should multiply by 10^-3 instead of 10^3. Interstingly, even assuming that the unit of rhocgs is [g m-3], the result is still incorrect.

I have been troubled by this question for a long time and expecting an explanation.

screenshots of module_mp_fast_sbm.F:

screenshots of module_microphysics_driver.F:

Now the problems are coming, an example: QG(I,K,J)=QG(I,K,J)+(1./RHOCGS(I,K,J))*COL*chem_new(I,K,J,KR)*XG(KRR)*XG(KRR)*3, I extrapolate from the entire file that the chen_new's unit is [g-1 cm-3], XG's unit is g, and the unit of QG is [kg kg-1], if the unit of rhocgs is [g cm-3] then the resulting unit correspond.

However, the next statement "QNG(I,K,J)=QNG(I,K,J)+COL*chen_new(I,K,J,KR)*XG(KRR)*3/rhocgs(I,K,J)*1000", the unit of QNG is [kg-1,] now we still assume that the unit of rhocgs is [g cm-3], if we want to do that, it should multiply by 10^-3 instead of 10^3. Interstingly, even assuming that the unit of rhocgs is [g m-3], the result is still incorrect.

I have been troubled by this question for a long time and expecting an explanation.

screenshots of module_mp_fast_sbm.F:

screenshots of module_microphysics_driver.F:

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