CMAQ v5.3.3 DESID is not working for Standard dev

I changed the diameter and standard deviation for new sources.
They were showing changes in particle number (Aitken and accumulation number)
But when I changed Standard Deviation only. I cannot see any differences between the result before applying new sources (default).


Can you send also the lines in your new Emission Control file where you have implemented the new distributions that you have added here?

Can you also provide some details on which sources you tried to modify and what domain and spatial resolution you are looking at? If you are only changing the Standard Deviation of Aitken mode particles from aircraft sources, for example, that may be a signal that is hard to see on a 12 km grid.

Best wishes,

I am using 1.33 km X 1.33km
Default = Changing GSD
Default =! Diameter only
Diameter only = Changing (Diameter + GSD)

I think GSD will be applied as default value.

Thank you,

This looks correct so far. Now, in the runscript, are you using the AIRPORT label for one of the emission files?


Sure. or not Geometric diameter must be not working as well.

If you inspect one of the CTM_LOG files (search for AIR_FINE for example), are all of the reference modes being used for each source as desired?

Even though I changed only GSD, it applied well based on the LOG.

Now, I have changed default Geometric Standard Deviation (GSD), and waiting for the result.

Variable: Aitken Number

Base > Default (Geometric Diameter; GD and Geometric Standard Deviation; GSD) with any number changes the results are showing the same values.

Assume that we have the same volume emission,
if I change the 60 nm (GD default) → 20 nm (less than default), I might get more number concentration.
But when I get the Aitken number result, 60 nm is higher than 20 nm. (60 nm - 20 nm = positive)

e.g., variable is Aitken Number.
All the results are the same, applying to any number and emission.
Default emission: aitken GD (10nm) = aitken GD (100nm) = aitken GSD (1.2) = aitken GSD (1.9)
= Airport only emission: aitken GD (10nm) = aitken GD (100nm) = aitken GSD (1.2) = aitken GSD (1.9).


Thank you for compiling all of these tests and sharing your results. I finally had some time today to run some test cases with v5.4, and I don’t see the same behavior.

When I change the GMD for the Aitken mode emissions to 20 nm instead of 60 nm, I get larger number emissions. Also, when I change the GSD from 1.7 to 1.9, I see larger number as well.

Would you be able to output emission diagnostic files with NUMATKN and SRFATKN on them to confirm that the emissions are actually behaving inconsistent with expectations?

Best regards,

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After re-compiling, it is working well!

Thank you so much

Ah, terrific! I’m so glad you figured it out. Please let me know if you see anything else fishy.