CMAQv5.2 benchmark difference

Hi all,

I built and ran CMAQv5.2 without any error. Here is the rum cctm log file

I downloaded reference data from


tar xzvf CMAQv5.2_Benchmark_SingleDay_Output_09_05_2017.tar.gz

I do see two ACONC files in the dir

-rw-r--r-- 1 jhuang hpc  174445528 Aug 31  2017
-rw-r--r-- 1 jhuang hpc  174445528 Jun 28  2017

Here are all my reference files


My simulations have <0.5% difference for O3 compared with

but show large difference for O3 compared with

Also large difference compared with reference data when I ran multiday simulations

I am a little confused here, what data I should use for benchmark run?

Thank you.


can I see your config_cmaq.csh and bldit.cctm?

Hi Peng,

Here are my config and bldit,

Thank you very much.


I want to calculate benchmarking difference. How did you calculate the difference between your simulations and benchmark files? could you guide me, please?
Thank you



The easiest way is using VERDI, you can add two files and add the species you would like to compare into formula, and make a quick plot.

You can also use m3stat or m3diff (from m3tools) to see the overall differences between two files.

If you would like to investigate the detail differences in each grid at each time step, you can use ncl/R/python, read the files, and subtract data in one file from another file.


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M3Tools program m3diff does that also…

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Thank you very much.

I have a question about benchmarking. Why we have different errors for different species? For example, my maximum error for ozone is 0.08%, but for NO2 is 4.5%! Why we don’t have similar errors for all of the species??
Thank you