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Open Source EMEP/MSC-W model
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OXN definition #82

Closed mvieno closed 9 months ago

mvieno commented 3 years ago

Hi, the OXN definition differs between what is in the model (CM_ChemGroups_mod.f90): OXN_GROUP = (/ & NO, NO2, NO3, N2O5, HONO, HNO3, HO2NO2, SC4H9NO3, NALD, & ISON, PAN, MPAN, NO3_f, NO3_c, shipNOx & /)

and what it say in the https://emep.int/mscw/mscw_moddata.html: Oxidised Nitrogen OxN (HNO3+NO3) --- SURF_ugN_OXN

Massimo

mvieno commented 3 years ago

Also, some clarification on the emissions units in the NetCDF output. The units of Emis_mgm2_nox and Emis_mgm2_sox are mg/m2/yr as NO2 and SO2, respectively, and Emis_mgm2_BioNatNO mg/m2/yr are as NO?

mifads commented 3 years ago

Hi Massimo. I think that at some stage there was a kind of total-nitrate species, which was for comparison with filterpack data. That would be HNO3 + NO3_f (+ NO3_c perhaps). I would have been inclined to call that combination total-nitrate, but we had a TNO3 in the old system for NO3_f+NO3_c anyway (now this group is called pNO3).

I cc this to @andagit @svetlanat @hildefagerli in case anyone knows why that msc_moddata.html document has just HNO3+NO3, and to make sure that our verification system is not assuming that OXN is just those 2 components.

About your 2nd comment, then yes, "nox" is treated as NO2, and "sox" as SO2, consistent with EMEP emissions practice. The Emis_mgm2_BioNatNO is for the specific species NO, and is mg(NO)/m2.

mvieno commented 3 years ago

@mifads Thanks

svetlanat commented 3 years ago

I cannot immediately answer about the documentation. As to verification, we evaluate the model for 'total NO3'= HNO3 + pNO3. I cannot recall I ever made verification for OXN. Cheers!

mifads commented 9 months ago

Two years since this issue - all seems well, so closing.