Output BVOC species mixing ratios in CAM6

[James King]

Hi all,

I'm a CESM2 novice interested in BVOC emissions. I'm planning some runs using a CESM2 build that couples CLM5 and CAM6. I know that the MEGAN model in CLM5 produces various BVOC species and that CAM6 can be set to show the MEGAN fluxes from the land to the atmosphere by adding the required fields to the namelist (e.g. MEG_ISOP for isoprene). I can also see that MOZART converts MEGAN species into its own output fields (e.g. ISOP) for which concentrations are output in %mol (mol/mol). Is there a way to output the concentrations directly as mixing ratios, or should I just calculate this manually from the output?

Cheers,

James

 

[cacraig]

I am moving this to the CAM-Chem forum as they maintain MOZART

 

[rrbuchholz]

Hi James,

My understanding is we generally use mole fraction as equivalent to volume mixing ratio, i.e. the model essentially already outputs as mixing ratios. For example a mole fraction of 10^{-6} is ppm(v) and mole fraction 10^{-9} is ppb(v).

I hope that helps.

Best,
Rebecca

 

[James King]

Hi James,

My understanding is we generally use mole fraction as equivalent to volume mixing ratio, i.e. the model essentially already outputs as mixing ratios. For example a mole fraction of 10^{-6} is ppm(v) and mole fraction 10^{-9} is ppb(v).

I hope that helps.

Best,
Rebecca

Thanks Rebecca, that makes sense.