Hello,
I have a plan to use the 2022 CRACMM chemical mechanism and have a question regarding the treatment of airport emissions.
Whether the provided 2022 CRACMM emissions inventory includes a airport sector? I downloaded from Making sure you're not a bot!
If an airport sector exists, what is the recommended way to extract or isolate this sector from the CMAQ-ready emissions files?
Thank you.
CRACMM emission-separated sectors
Airports are lumped with other sources in the merged 2-D emissions at merged_nobeis_norwc. Do you need that sector separate? Aircraft organic aerosol emissions are represented as semivolatile (Table S9).
Thank you for answering the question.
I want to make a background emissions without the airport sector.
With Table S9, I could calculate the speciation but not the quantity of airport emissions.
Do you have any ideas?
Yes
Yes I need airport emission as separated file.
Thank you for airport emissions.
Thank you so much for your help.
@lizadams is working on posting the airport emission files for 2022. We may keep them in a separate location as they are not needed by default as they are in other files.
Thank you.
Do you guys have a plan to provide rwc only, not airports and beis for CRACMM?
CB6 usually provides with pre-merged sectors for rwc, airports, beis as default with pre-run period for January.
Thank you for your work!
Inputs produced by ORD (which include these) do not have premerged biogenics/beis. ORD configurations generally rely on the in-line BEIS emissions. Input files for inline BEIS should be in the surface or misc folders. I’ll follow-up on the pre-merged sectors.
I will try to use in-line BEIS emissions
I have a quick question regarding CRACMMv2 about aircraft sources in your 2026 ES&T paper.
Based on Table S9, it appears that aircraft POA is speciated only into the lowest volatility alkane species. Am I interpreting this correctly?
If so, does this also mean that there are no aircraft S/IVOC gas phase emissions (or SVOC/IVOC speciation) included in the inventory? In other words, aircraft emissions are represented only as LVOC in CRACMMv2, without emitted S/IVOC precursors available for SOA formation.
I wanted to confirm that I am interpreting the speciation correctly
Table S9 shows mass in ROC- N2ALK, N1ALK, P0ALK, P1ALK, and P2ALK species which correspond to C* of 10^-2 through 10^2 (LVOC to SVOC). They are emitted in the particle phase as they are from the PM2.5 emission inventory. CMAQ assumes equilibrium partitioning, so some of the mass will volatilize.
There are no lumped gas phase S/IVOC emissions in the 2022 platform for airports but there could be speciated S/IVOC emissions from airport. For example, anthracene and acenaphthene are S/IVOCs and map to NAPH in CRACMM2.
You probably can’t extract it back out of merged emissions, but check if the source inventory before CMAQ processing is available — that’s where the airport breakdown would be.
