Some questions about using different resolution OMI file in CMAQ5.3.2

Hi everyone.
I’m trying to run CMAQv5.3.2 simulations in East Asia.
I use the program which in the folder “CMAQ5.3.2/PREP/create_omi” to create high resolution OMI file.I set up nlat = 719, and nlon = 1441.
I have successfully run the case, but the result is very different with using the default OMI file.
When I check the IRR file, I found that the result using high resolution OMI file has some error.

I also try to use low resolution OMI file.I set up nlat = 361, and nlon = 361.
The result is very similar with using the default OMI file.

This picture is useing default OMI file(17x17).

This picture is useing OMI file(361x361).

This picture is useing OMI file(719x1441).

I have no idea why this problem happened.
Could you suggest me how to solve this problem?

Thanks!

How high is the resolution of the OMI data? Is it reasonable to generate data at the resolution you are attempting? Have you visualized the ozone column data, as done here?

The resolution of raw satellite is 0.25 degree.
The resolution of omi data is nlat = 719, and nlon = 1441.

Yes, I have visualized the ozone column data.
The result is very similar with the picture in PREP/create_omi/image_files.

This one is my omi data on 2018/05/10
image

This one is example in CMAQ folder.
image

And this one is the omi data on 2016/03/16.
This day is the second day in my simulations.
image

Thanks!

For the CMAQ OMI file with 719X1441 resolution, format statements may cause daily data to not be written on one line.

Please make and test the below changes to PREP/create_omi/src/module_utilities.f. The exact line numbers may be off based on your text editor but I hope that you understand these suggestions.

  1. Change lines 268 and 269 to

    550   format(a19,3600001f7.2)
    555   format(f10.4,f7.1,3600001i7)
    
  2. Change lines 647 and 648 to

    550   Format(2(a,tr1),3600001(f7.2,tr1))
    555   Format(f9.4,tr1,f7.1,tr1,3600001(i7,tr1))
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Hi bhutzell,
Thank you for your help.
I have changed the code and created the new OMI file with 719X1441 resolution.
The output of IRR_10 became correct!
This picture is useing FIX OMI file(719x1441).

This fix is working for me as well!
Thank you so much for your help!

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