AQCHEM maximum iterations exceeded


I am running CMAQv5.2.1 for nest simulation. But it crashed for certain days with the AQCHEM error: maximum iterations exceeded. There is no NaN or Infinity showing up in my log files.

I know this is caused by MCIP generated METCRO2D file. Because when I run that day with a fake METCRO2D file (copied from other days), it ran well. However, I checked the RC and RN values in the METCRO2D file. There is no negative or unreasonable large value. I don’t know what else in the METCRO2D could cause this error.

Any help is appreciate on how to solve this issue.

Thank you so much

Jay - have you been able to resolve this issue?
@tlspero do you have an idea of how to diagnose this problem?

It was caused by my mistake on GRIDDESC file. I set the cell thickness wrong. After I changed it to 1, it runs fine. Your error may be caused by other reasons. But I found my mistakes by turning on debug option while running CMAQ.

Good luck to you.

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