Calculation of PMF_H2O in the ELMO module

CMAQ
1

I found a discrepancy between AH2OI + AH2OJ from ACONC outputs and PMF_H2O from AELMO outputs. My understanding is that ELMO’s PMF variables should represent sum of I and J modes. Both ACONC and AELMO output files show the units of these variables to be ug m-3, so I assume the discrepancy is not due to a unit conversion.
Then, I found that in ELMO_PROC.F:

             ! Map PMF_H2O - Fine-Mode Particle Water
             CASE ( ID_PMF_H2O )
               N_VARS = 1
               CALL INIT_ELMO_COEFFS( IDG, N_VARS, 'FINE' )
               CALL SET_ELMO_COEFF_MAP( IDG, 1, 'AERO', 'AH2O', 1.0/19.0 )

Indeed, AH2OI + AH2OJ from ACONC and PMF_H2O from AELMO differ by a factor of 19.
I wonder what this factor of 19 represent. Could anyone please clarify this?

2

Thanks Bonyoung,

The factor should be 1.0 as you point out. I believe I made a typo here in using the function call for ID_PMF_HP and failing to update the last input parameter.

-Ben

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