# Vertical Allocation of CMAQ emissions

**URL:** <https://forum.cmascenter.org/t/vertical-allocation-of-cmaq-emissions/4128>\
**Category:** CMAQ\
**Created:** [May 20, 2023, 1:52pm UTC](https://forum.cmascenter.org/t/vertical-allocation-of-cmaq-emissions/4128 "2023-05-20T13:52:26Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Yiyue](https://avatars.discourse-cdn.com/v4/letter/y/977dab/32.png) [@Yiyue](https://forum.cmascenter.org/u/Yiyue)\
**Post date:** [May 20, 2023, 1:52pm UTC](https://forum.cmascenter.org/t/vertical-allocation-of-cmaq-emissions/4128/1 "2023-05-20T13:52:26Z")

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Hi all,

I’m converting CMAQ-ready-to-use emission files to wrfchemi\* files. I have 34 layers for my WRF/Chem emission, but there’s only 1 layer in the CMAQ emission. I think I need to do vertical allocation for them, but just don’t know how to do that. Does anyone have advice for me? I’ll highly appreciate that!

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**Author:** ![lizadams](https://avatars.discourse-cdn.com/v4/letter/l/49beb7/32.png) [@lizadams](https://forum.cmascenter.org/u/lizadams)\
**Post date:** [May 30, 2023, 2:52pm UTC](https://forum.cmascenter.org/t/vertical-allocation-of-cmaq-emissions/4128/2 "2023-05-30T14:52:26Z")

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Do you have both gridded and point source emission files that you are trying to use? If you have point source files with stack information then we do not have a tool for recomputing plume rise in WRF-CHEM.

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**Author:** ![bigboy1](https://avatars.discourse-cdn.com/v4/letter/b/c68b51/32.png) [@bigboy1](https://forum.cmascenter.org/u/bigboy1)\
**Post date:** [June 16, 2024, 3:30am UTC](https://forum.cmascenter.org/t/vertical-allocation-of-cmaq-emissions/4128/3 "2024-06-16T03:30:46Z")

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Hello! Did you fix this, I had the same situation, using CMAQ to simulate a layer of one. I don’t know how to modify it to simulate vertical multi-layers.

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**Author:** ![james.beidler](https://avatars.discourse-cdn.com/v4/letter/j/6f9a4e/32.png) [@james.beidler](https://forum.cmascenter.org/u/james.beidler)\
**Post date:** [June 17, 2024, 12:57pm UTC](https://forum.cmascenter.org/t/vertical-allocation-of-cmaq-emissions/4128/4 "2024-06-17T12:57:46Z")

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2D CMAQ-ready emissions files can be vertically layered with the SMOKE tool layalloc, provided that you have a set of MET\_CRO\_3D files on the corresponding grid and your target layer allocation fractions.

[https://www.cmascenter.org/smoke/documentation/5.0/html/ch03s03s08.html](https://www.cmascenter.org/smoke/documentation/5.0/html/ch03s03s08.html)

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**Author:** ![bigboy1](https://avatars.discourse-cdn.com/v4/letter/b/c68b51/32.png) [@bigboy1](https://forum.cmascenter.org/u/bigboy1)\
**Post date:** [June 23, 2024, 3:19am UTC](https://forum.cmascenter.org/t/vertical-allocation-of-cmaq-emissions/4128/5 "2024-06-23T03:19:23Z")

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First of all, thanks for your reply！Do you mean that you need to relocate the 2D emissions file to 3D? The original model setup used MCIP to generate METCRO3D, and when I read 29 layers of contaminant data using python, I found that they changed very little, is that reasonable?