I have an issue about my CMAQ simulation over California, as shown below. May I ask what should I do to pass QG to the MET_CRO_3D file? Do I need to revise the source code of MCIP and recompile it or upgrade the MCIP version?
Any suggestions are highly appreciated!
In my opinion, this warning message is unnecessarily alarming; there is probably no error here.
The message is saying that graupel, cloud ice, and snow are not present in the MCIP files. MCIP passes through what it finds in the WRF output. There is not really a need to check whether those hydrometeors were actually present in the WRF outputs and MCIP somehow failed to find them.
You might consider rerunning WRF with a more sophisticated microphysics scheme that generates those hydrometeors, so that MCIP could pass them through and CMAQ could use them. However, I am not aware of any studies examining the impact of differing microphysics schemes on photolysis and/or air quality.
If graupel were part of the microphysics scheme that you used in WRF, then it would automatically be sent through MCIP to become available for CMAQ. I think the warning message in CMAQ is OK; it means that your data will be processed without using graupel…which is fine if you don’t have it. There is the outside chance that you would be using a newer microphysics scheme that might not conform to the assumptions in MCIP for processing and passing through graupel. So it’s always a good idea to check to be sure that I have not overlooked something in coding up MCIP to handle the proliferation of microphysics schemes in WRF.
If you find a case where graupel is available in your WRF output but was not passed through MCIP into METCRO3D, please write back so it can be addressed properly.