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How to convert mass emission (kg/m2/s) to emission (molecules/cm3/s)?

xnnzka

xnnzka
New Member
Hi, everyone. I have 1 question about the unit convertion.

I want to use CEDS emission data to simulate. I want to use the emission from aircraft so I think I must convert its unit (kg/m2/s) to molecules/cm3/s. I try to calculate but I do not know if my calculation is right.

My calculation is:
y (molecules/cm^3/s)= Emissions (kg/m^2/s) × N_Av (molecules/mol) ÷ MW (g/mol) × 1000 (g/kg) ÷ 1000000 (cm^2/m^2) ÷ altitude interface (km, I found the altitude interface=0.61km, so here I fix it to be 0.61) ÷ 1000 (km/m)
(ps:the level (i.e., altitude) of CEDS data is:level = 0.305, 0.915, 1.525, 2.135, 2.745, 3.355, 3.965, 4.575, 5.185, 5.795, 6.405, 7.015, 7.625, 8.235, 8.845, 9.455, 10.065, 10.675, 11.285, 11.895, 12.505, 13.115, 13.725, 14.335, 14.945 km)

But compared with emissions-cmip6_SO2_aircraft_vertical_1750-2015_0.9x1.25_c20170608.nc, I found my results was about 10^1 times smaller.
I suspect there might be wrong with my calculation process but I do not know how I can solve it.

I need your help!
 
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