Questions on NOₓ Allocation Factors

Hi teachers,

I am wondering how do you set the allocation factors when distributing NOₓ across different sources? I think I have to set it in gsref and gspro files under /ge_dat/EDGAR path.

I have a scheme where: NO: 0.9 NO₂: 0.092 HONO: 0.0080

I’m not sure if this allocation applies to all sources, including industrial sources, biomass burning sources, etc… Could you provide any insights on this?

EDGAR-HTAP BC is mapped to PEC in our hemispheric applications, although I’m not sure if you need to rename it to PEC prior to processing.

Our standard for NOx in regional modeling is:

For mobile sources (onroad*, nonroad, rail, CMV, airports): NO: 0.9 NO2: 0.092 HONO: 0.0080 (* for onroad, the NO/NO2 ratios are determined within MOVES and vary somewhat)

For everything else: NO 0.9, NO2 1.0, HONO 0

Historically for hemispheric modeling / EDGAR-HTAP inventories, we have only used the 90/10 NO/NO2 split with no HONO. But there’s no technical reason why the HONO profile couldn’t be used for EDGAR-HTAP, although based on what we do for regional modeling, it should only be applied for mobile / transport sectors.

Hi alison, thank you for your reply. I am confused that shouldn’t NO2 0.1 for non mobile source. Or the sum of NO and NO2 would be 1.9 rather than 0.1?

Apologies – it should be: NO 0.9, NO2 0.1, HONO 0

ok I see. Thank you alison!