The detail information of compounds in MEGANv3.2

MEGAN
1

Hi everyone
I want to plot the Monoterpenes and Sesquiterpenes in the MEGANv3.2 output. But there are no Monoterpenes and Sesquiterpenes compounds list like one in MEGANv2.1. The only information I can find is:

1717397789108
17173977891081733×978 238 KB

Does anyone know the detailed compounds of the Monoterpenes and Sesquiterpenes in MEGANv3.2?
Thanks

2

Do you mean you want to write out emissions for those 19 classes from MEGAN 3.2? Are you running MEGAN 3.2 independently or running it within CMAQ? If you’re running MEGAN as part of CMAQ then there is no output file with those 19 classes. The only diagnostic output is the speciated emissions that are used with CMAQ (with DESID).

If you’re running MEGAN 3.2 independently then those files are created from the MEGVEA step.

If you want the full breakdown of all species then you will need to add code to create another IOAPI output file in the mgn2mech program.

3

Hi willison.jeff
Thank you for your reply. I run MEGAN 3.2 independently.
I want to know individual compounds in each MEGAN 3.2 compound class, but I can’t find this information.
Thanks again

4

I might misunderstand the question (and it might be a question for the MEGANv3.2 developers who are not active on this forum), but I think you could look at the following file from the CMAQ source code to obtain a list of all the native MEGANv3.2 species (e.g. “myrcene”, “ocymene_al”, etc.) that map to the CB6 species “TERP”, “APIN”, and “SESQ” to get a sense of which of the native MEGANv3.2 species are monoterpenes and sesquiterpenes

CCTM/src/biog/megan3/MAP_CV2CB6_AE7.EXT

For example, lines 52 - 57

  DATA  SPMH_NAM_CB6_AE7( 4)     , SPMH_MAP_CB6_AE7( 4)
 &    / 'pinene_a     ', 3           /
  DATA  MECH_NAM_CB6_AE7( 4)     , MECH_MAP_CB6_AE7( 4)
 &    / 'APIN      ', 35           /

show that the native MEGANv3.2 species “pinene_a” maps to CB6 species “APIN” which is a monoterpene.

Lines 59 - 330, 808 - 813, 843 - 848, 878 - 883, and 941 - 946 list 45+ other native MEGANv3.2 species that map to CB6 species “TERP”.

Lines 332 - 645 list 35+ native MEGANv3.2 species that map to CB6 species “SESQ”

There may be a more concise depiction of the mapping (similar to the image you included in your first post) somewhere else, but the data in the piece of code linked above should be a good starting point.

5

As @hogrefe.christian has pointed out, those mappings are in the .EXT files that get used by MGN2MECH. If you want the result of those mappings then you’ll have to edit that program to make a new output file. If I’m understanding correctly I think what you want are the speciated species before they’re lumped to a mechanism, which is the tmper field:

   !-----------------------------------------------------------------------
   !.....3) Conversion from speciated species to MECHANISM species
   !-----------------------------------------------------------------------

    DO s = 1, n_spca_spc
       tmper(s,:,:) = tmper(s,:,:) * nmol2mol
          ! WRITE TO IOAPI FILE HERE
    ENDDO
6

Hi hogrefe.christian
Thank you very much.

7

Hi willison.jeff
Thank you very much.