NOx and NH3 of the FCHIST

[wrunyu]

Hi all,
I'm using the FCHIST mode of the CESM 2.1.3 and I'm using the model to run sensitivities for NOx and NH3. I have two problems:
1.The model output results are in mol/mol, how should I convert them to ug/m-3.(especially NOY，noy = total nitrogen (N+NO+NO2+NO3+2N2O5+HNO3+HO2NO2+ORGNOY+NH4NO3))
2.There are no direct results for ammonium aerosol and nitrate aerosols in the run results, which commands should I add to output the results.
Looking forward to your reply.

Regards,
Runyu

 

[nusbaume]

Hi Runyu,

I am moving your post to the CAM-Chem forum, as they will be the group who can most likely answer your questions.

Hope that helps, and have a good weekend!

Jesse

 

[Danny Leung]

Hi wrunyu-

1. If you have a chemical tracer X (for your case X = NOy) in the molar mixing ratio with a unit of mol X / mol air, you can first convert it to the mass mixing ratio by
X (kg X / kg air) = X (mol X / mol air) * molarmass_X (kg X/mol X) / molarmass_air (kg air/mol air)
where molarmass_air = 28.96 g air / mol air is a typical value.
One you have X (kg X / kg air) as mass mixing ratio, you can convert X to mass concentration (μg X / m3 air) by
X (μg X / m3 air) = X (kg X / kg air) * density_air (kg air / m3 air) * 10^9 (μg X / kg X)
where density_air can be obtained by using history outputs of temperature and pressure with the ideal gas law, or alternatively you can directly output air density (RHO_CLUBB) as a CAM history variable.

2. Right, to my knowledge there are no simulations of the ammonium and nitrate aerosols in the default CAM-Chem. You will need to download the source code for a version of CAM-Chem coupled with the MOSAIC and then run your simulation again. See instruction on this page: Use MOSAIC scheme in CESM/CAM-chem - CAM-Chem - wiki.ucar.edu

Hope this helps!
Danny

 

[rrbuchholz]

Hi wrunyu,

Danny answered your questions well. He is correct about the default aerosol simulation - some expanded information from Louisa Emmons:

Ammonium aerosol is simulated in a very simplified manner (in the default) primarily to keep track of the deposition of nitrogen to the land model. It is called 'NH4'. Nitrate aerosols are not simulated in CESM2.1.3.

Best,
Rebecca

 

[wrunyu]

Hi wrunyu-

1. If you have a chemical tracer X (for your case X = NOy) in the molar mixing ratio with a unit of mol X / mol air, you can first convert it to the mass mixing ratio by
X (kg X / kg air) = X (mol X / mol air) * molarmass_X (kg X/mol X) / molarmass_air (kg air/mol air)
where molarmass_air = 28.96 g air / mol air is a typical value.
One you have X (kg X / kg air) as mass mixing ratio, you can convert X to mass concentration (μg X / m3 air) by
X (μg X / m3 air) = X (kg X / kg air) * density_air (kg air / m3 air) * 10^9 (μg X / kg X)
where density_air can be obtained by using history outputs of temperature and pressure with the ideal gas law, or alternatively you can directly output air density (RHO_CLUBB) as a CAM history variable.

2. Right, to my knowledge there are no simulations of the ammonium and nitrate aerosols in the default CAM-Chem. You will need to download the source code for a version of CAM-Chem coupled with the MOSAIC and then run your simulation again. See instruction on this page: Use MOSAIC scheme in CESM/CAM-chem - CAM-Chem - wiki.ucar.edu

Hope this helps!
Danny

Hi Danny，
Thank you very much for your reply.This has been of great help to me. I will follow the ideas you provided. Have a nice day!

Regards,
Runyu

 

[wrunyu]

Hi wrunyu,

Danny answered your questions well. He is correct about the default aerosol simulation - some expanded information from Louisa Emmons:


Best,
Rebecca

Hi Rebecca
Thank you very much for your reply. I would like to ask: can the MOSAIC coupling with CAM-Chem be realized in the CESM 2.1.3 model? Have a nice day!

Regards,
Runyu

 

[wrunyu]

Hi Runyu,

I am moving your post to the CAM-Chem forum, as they will be the group who can most likely answer your questions.

Hope that helps, and have a good weekend!

Jesse

Hi Jesse
Thank you very much. I got a response to my question. Have a nice day!

Regards,
Runyu

 

[wrunyu]

Hi wrunyu-

1. If you have a chemical tracer X (for your case X = NOy) in the molar mixing ratio with a unit of mol X / mol air, you can first convert it to the mass mixing ratio by
X (kg X / kg air) = X (mol X / mol air) * molarmass_X (kg X/mol X) / molarmass_air (kg air/mol air)
where molarmass_air = 28.96 g air / mol air is a typical value.
One you have X (kg X / kg air) as mass mixing ratio, you can convert X to mass concentration (μg X / m3 air) by
X (μg X / m3 air) = X (kg X / kg air) * density_air (kg air / m3 air) * 10^9 (μg X / kg X)
where density_air can be obtained by using history outputs of temperature and pressure with the ideal gas law, or alternatively you can directly output air density (RHO_CLUBB) as a CAM history variable.

2. Right, to my knowledge there are no simulations of the ammonium and nitrate aerosols in the default CAM-Chem. You will need to download the source code for a version of CAM-Chem coupled with the MOSAIC and then run your simulation again. See instruction on this page: Use MOSAIC scheme in CESM/CAM-chem - CAM-Chem - wiki.ucar.edu

Hope this helps!
Danny

Hi Danny,

I tried to follow the web page steps to download. Because of the network settings, I can't use the code “git clone GitHub - ESCOMP/CAM: Community Atmosphere Model -b zz_cam6_3_018_mosaic0.3 your_mosaic_directory”. I manually downloaded it from the webpage and extracted it to “/home/wrunyu2023/cesm2.1.3/components/cam”. When I run the code “. /manage_externals/checkout_externals” the output appears as shown below. I didn't know how to fix it, so I built the FCHIST case directly. But I run the code “. /case.build”, an error was reported.I checked the error reported in atm.bldlog: ImportError: cannot import name get_standard_makefile_args.I would very much like to seek your help.If you have a solution for this, I would appreciate it.

Regards,
Runyu

 

[rrbuchholz]

Hi wrunyu,

Hi Rebecca
Thank you very much for your reply. I would like to ask: can the MOSAIC coupling with CAM-Chem be realized in the CESM 2.1.3 model? Have a nice day!

Regards,
Runyu

I believe the branch is only available on that specific tag of the model (CESM Version 2.0). There are some hard-coded aspects that would need to be updated in more recent versions.

Best,
Rebecca

 

[Danny Leung]

Hi Danny,

I tried to follow the web page steps to download. Because of the network settings, I can't use the code “git clone GitHub - ESCOMP/CAM: Community Atmosphere Model -b zz_cam6_3_018_mosaic0.3 your_mosaic_directory”. I manually downloaded it from the webpage and extracted it to “/home/wrunyu2023/cesm2.1.3/components/cam”. When I run the code “. /manage_externals/checkout_externals” the output appears as shown below. I didn't know how to fix it, so I built the FCHIST case directly. But I run the code “. /case.build”, an error was reported.I checked the error reported in atm.bldlog: ImportError: cannot import name get_standard_makefile_args.I would very much like to seek your help.If you have a solution for this, I would appreciate it.

Regards,
Runyu

Hi Runyu-
I think as Rebecca said, you cannot just copy the source code of the cam component to your CESM2.1.3 to replace your cam; there will be some software engineering needed because of the MOSAIC and because of the version differences (this CAM6.3.018 tag is closer to a CESM2.2 tag).
Danny