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Ice mixing ratio cat 2 in P3

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Dear colleges,

Can you clarify if the "QICE2" "Ice mixing ratio cat 2" represents only snow in P3 scheme (mp=52)?
And the "QICE" "Ice mixing ratio" "kg kg-1" is the sum of ice+graupel+snow?

Kind regards,
I do not see any use of QICE2 or QICE in the P3 microphysics scheme. Are you certain that's the one you're using?

The mp option 52 has two ice arrays (ice category one and ice category 2) since version 4.0. Therefore, QICE and QICE2 variables are produced in wrfout files. You can find that variable also in the Registry.EM_COMMON file.
I apologize. I was only looking for QICE2 and not qi2, as it's listed in the actual code. I am actually not sure, and not able to figure it out based on the code. We will have to get in touch with someone who may know the code a bit better and get back to you.
I apologize for the delay. I sent your question to someone who knows the physics routines a bit better. They said that QICE and QICE2 are both combined ice particles that can be ice/snow/graupel, depending on the other properties at that point. There is no real difference between QICE and QICE2 except they initialize QICE2 for new clouds under some criteria.