compute column density from mixing ratio

[pybl]

Hello,

I am trying to get some hints for computing column density of molecules of interest (i.e, O3) from their mixing ratio (mol/mol).

I am using WACCM6, the mixing ratio can be found in the history files.

Thanks in advance!

 

[Rgh]

I have a same question!
I appreciate any hints!
Thanks

 

[dbailey]

I am moving this to the Chemistry forum.

 

[rrbuchholz]

Hi All,

To convert mixing ratio to total column amounts (e.g. molec./cm^2) you need to calculate a pressure weighted sum. If you have saved PDELDRY from the model, you can use this variable. Otherwise, you can calculate the model pressure differences from the surface pressure and hybrid coordinate definitions.

Here is link to an example of doing that for CO in python:
Python Resources for CAM-chem

Attached is a document that describes the process.

Hope that helps!
Best,
Rebecca

 

[Rgh]

Thank you very much Rebecca for your response.
What about getting for example O2 density in molecules/cm3? In the masterlist I can see N2_dens in molecules/cm3 directly, but for other gases like O2 I just have the concentration in mol/mol.
In this case can I use M_dens (molecules/cm3) and multiply concentrations by that to get O2 density?
Thanks