Issues regarding CCTM output

Dear all,
When I am running CMAQ, I always get the log file with the title of FLOOR***. I entered the file and found that it reported the negative concentration which had been automatically adjusted by CMAQ.
I want to know whether this issue will cause any effects on modeling results?
(The CMAQ finished the whole simulation and didn’t crash while I got several FLOOR files.)
Please find the FLOOR file in the attachment.
Any explanations are appreciated!

Best,
RyanFLOOR_033.2017-10-BASE_20170921.txt (1.7 KB)

In general, FLOOR files are an indication of something going wrong. If they happen rarely, that may be acceptable, but if you get a lot of them, and they have many entries, then the cause should be found and fixed.

You do not indicate whether this was the entire FLOOR file, or whether this is an excerpt. The only species that is shown is ISOP (isoprene). What is the case you are modeling? Have you done something to modify isoprene chemistry or dry deposition?

Hi Chris,
I didn’t revise the isoprene chemistry and just run the general way of CMAQ. I only get one FLOOR file (attached above). Based on your explanation, I guess my modeling results are acceptable.
Thanks a lot for your explanation!

Regards,
Ryan