# \#cmaq-isam

**URL:** https://forum.cmascenter.org/tag/cmaq-isam/66.md

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## [ISAM mass imbalance in output](https://forum.cmascenter.org/t/isam-mass-imbalance-in-output/6242)

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**Author:** [@calvinhowes](https://forum.cmascenter.org/u/calvinhowes)\
**Replies:** 7\
**Last updated:** [September 21, 2026, 12:03pm UTC](https://forum.cmascenter.org/t/isam-mass-imbalance-in-output/6242 "2026-09-21T12:03:07Z")

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I’m running into a mass balance issue using ISAM. When I run CMAQ with a tagged emissions stream in ISAM, I’m finding that there is a discrepancy for aerosol species in the sum of total streams vs. the output in the ACO…

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## [PM10 from ISAM results](https://forum.cmascenter.org/t/pm10-from-isam-results/6084)

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**Author:** [@nosha\_assare](https://forum.cmascenter.org/u/nosha_assare)\
**Replies:** 1\
**Last updated:** [November 29, 2025, 11:50am UTC](https://forum.cmascenter.org/t/pm10-from-isam-results/6084 "2025-11-29T11:50:03Z")

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\*Hi All, I’ve run cmaq-ISAM v5.4, and when I look into PM10 ISAM results, I noticed that the coarse mode PM is not tracked properly and almost all PM10 contribution comes from PM2.5. I am not sure if I made any mistake …

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## [The ISAM marking area is re-running every day](https://forum.cmascenter.org/t/the-isam-marking-area-is-re-running-every-day/5950)

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**Author:** [@zxcRuan](https://forum.cmascenter.org/u/zxcRuan)\
**Replies:** 4\
**Last updated:** [August 28, 2025, 1:07am UTC](https://forum.cmascenter.org/t/the-isam-marking-area-is-re-running-every-day/5950 "2025-08-28T01:07:14Z")

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I am currently applying CMAQv5.3.2 for nested operation. When running source resolution with ISAM, the result of running 36 kilometers is fine. When running 12 kilometers of ISAM with the same script, after modifying the…

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## [Biogenic emissions using BIES](https://forum.cmascenter.org/t/biogenic-emissions-using-bies/5935)

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**Author:** [@Sam](https://forum.cmascenter.org/u/Sam)\
**Replies:** 3\
**Last updated:** [July 25, 2025, 12:07am UTC](https://forum.cmascenter.org/t/biogenic-emissions-using-bies/5935 "2025-07-25T00:07:41Z")

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I am using CMAQ 5.4 with ISAM for source apportionment. I used BIES for inline biogenic emissions but in the output, I am noticing that the biogenic emissions are very small. I am tracking POM in my ISAM control file for…

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## [Questions in CMAQ-ISAM output](https://forum.cmascenter.org/t/questions-in-cmaq-isam-output/5891)

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**Author:** [@Bailey](https://forum.cmascenter.org/u/Bailey)\
**Replies:** 1\
**Last updated:** [July 15, 2025, 3:52pm UTC](https://forum.cmascenter.org/t/questions-in-cmaq-isam-output/5891 "2025-07-15T15:52:58Z")

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Hello teachers, I encountered a problem while processing the ISAM output file. I have enabled the ISAM source apportionment function in the CMAQ 5.3.2 version. The ISAM control file has been uploaded. I would like to kn…