# LARGE AORGCJ\_BCO in CMAQ\_ISAM

**URL:** https://forum.cmascenter.org/t/large-aorgcj-bco-in-cmaq-isam/4413
**Category:** CMAQ
**Tags:** cmaq
**Created:** [September 19, 2023, 9:19am UTC](https://forum.cmascenter.org/t/large-aorgcj-bco-in-cmaq-isam/4413 "2023-09-19T09:19:32Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![nosha\_assare](https://avatars.discourse-cdn.com/v4/letter/n/ba8739/32.png) [@nosha\_assare](https://forum.cmascenter.org/u/nosha_assare)
#### Post date: [September 19, 2023, 9:19am UTC](https://forum.cmascenter.org/t/large-aorgcj-bco-in-cmaq-isam/4413/1 "2023-09-19T09:19:32Z")

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Hi,

I’m using CMAQ-ISAM v5.4. I’ve noticed that at certain hours, the value for PM2.5\_BCO in the CMAQ-SA file is exceptionally high (\> 10^18). However, the total PM2.5 in the AELMO files appears to be reasonable. Upon examining individual components, I identified that the anomaly stems from AORGCJ\_BCO, which also has unusually high values during those specific hours. For the rest of the hours, its value is fairly low, averaging between 0.02 and 0.1. Does anyone have insights or reasons for this discrepancy?

Thanks,  
Nosha

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### Author: ![hogrefe.christian](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@hogrefe.christian](https://forum.cmascenter.org/u/hogrefe.christian)
#### Post date: [September 19, 2023, 11:30am UTC](https://forum.cmascenter.org/t/large-aorgcj-bco-in-cmaq-isam/4413/2 "2023-09-19T11:30:27Z")

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Hi Nosha,

the unrealistic values of AORGCJ ISAM tags are a known issue in CMAQv5.4. This issue has been fixed in [CMAQv5.4.0.3](https://github.com/USEPA/CMAQ/pull/186), the updates are described [here](https://github.com/USEPA/CMAQ/pull/186) and are included in the [CMAQv5.4+ branch](https://github.com/USEPA/CMAQ/tree/5.4+). Updating your code to this release should fix the issue with the AORGCJ ISAM tags.

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### Author: ![nosha\_assare](https://avatars.discourse-cdn.com/v4/letter/n/ba8739/32.png) [@nosha\_assare](https://forum.cmascenter.org/u/nosha_assare)
#### Post date: [September 19, 2023, 1:19pm UTC](https://forum.cmascenter.org/t/large-aorgcj-bco-in-cmaq-isam/4413/3 "2023-09-19T13:19:39Z")

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@hogrefe.christian

Hi Christian,

Thank you so much for the clarification. I am gonna update the cmaq version then.

Thanks,  
Nosha