Contribution of mobile sources to secondary formation of carbonyl compounds

Figures & data

Figure 1. Map of the CMAQ modeling domain

Table 1. CMAQ performance statistics for 2014 NATA

Pollutant	Mean Bias (MB; µg/m^3)	Mean Error (ME; µg/m^3)	Normalized Mean Bias (NMB; %)	Normalized Mean Error (NME; %)
Formaldehyde	−0.9	1.0	−41.5	45.2
Acetaldehyde	−0.3	0.5	−21.8	35.5

Table 2. Short tons of emissions from mobile source, biogenic source, and stationary source sectors in 2014 NATA

Sector	Formaldehyde (% Total)	Acetaldehyde (% Total)	Acrolein (% Total)
Onroad	35,327 (2.89)	25,832 (3.19)	2,323 (4.54)
Commercial Marine Vessels	1,064 (0.08)	515 (0.06)	21 (0.04)
Aircraft	4,830 (0.39)	1662 (0.21)	945 (1.85)
Rail	1,112 (0.09)	483 (0.06)	80 (0.16)
Other Nonroad	35,756 (2.92)	14,147 (1.75)	2,542 (4.97)
Total Mobile	78,089 (6.38)	42,639 (5.27)	5,911 (11.55)
Biogenic	855,346 (69.90)	627,243 (77.50)	0
Fires	237,163 (19.38)	117,704 (14.54)	40,317 (78.81)
Stationary	52,997 (4.33)	21,811 (2.70)	4,930 (9.64)
All Sources	1,223,595	809,397	51,158

Table 3. Contribution of mobile source sectors to total ambient concentrations of carbonyls

Percentile	5%	25%	50%	75%	95%
Formaldehyde
Air/Rail	0.002	0.005	0.007	0.0100	0.018
CMV	0	0.0005	0.003	0.051	0.180
Onroad	0.022	0.041	0.057	0.077	0.111
Nonroad	0.007	0.014	0.020	0.032	0.055
Total Mobile	0.044	0.072	0.095	0.123	0.174
Biogenic	0.362	0.459	0.518	0.584	0.668
Fires	0.004	0.012	0.025	0.047	0.121
Acetaldehyde
Percentile
Air/Rail	−0.010	−0.007	−0.004	−0.002	0.000
CMV	−0.052	−0.014	−0.002	−0.001	0.000
Onroad	−0.031	−0.012	−0.001	0.015	0.057
Nonroad	−0.001	0.001	0.008	0.020	0.058
Total Mobile	−0.041	−0.017	0.000	0.028	0.105
Biogenic	0.575	0.712	0.802	0.855	0.918
Fires	0.009	0.020	0.040	0.064	0.139
Acrolein
Percentile
Air/Rail	−0.007	0.005	0.018	0.033	0.084
CMV	−0.343	−0.018	−0.003	−0.001	0.000
Onroad	−0.029	0.026	0.081	0.164	0.296
Nonroad	0.005	0.030	0.066	0.119	0.259
Total Mobile	−0.026	0.064	0.172	0.330	0.582
Biogenic	0.007	0.025	0.047	0.079	0.155
Fires	0.103	0.280	0.536	0.774	0.946

Figure 2. Absolute total concentration differences (column 1) and percent differences (column 2) from onroad zero out runs for carbonyls (FORM = formaldehyde; ALD2 = acetaldehyde)

Figure 3. Absolute total concentration differences (column 1) and percent differences (column 2) from nonroad zero out runs for carbonyls (FORM = formaldehyde; ALD2 = acetaldehyde)

Figure 4. Absolute total concentration differences (column 1) and percent differences (column 2) from biogenic zero out runs for carbonyls (FORM = formaldehyde; ALD2 = acetaldehyde)

Figure 5. Absolute total concentration differences (column 1) and percent differences (column 2) from fire zero out runs for carbonyls (FORM = formaldehyde; ALD2 = acetaldehyde)

Table 4. Contribution of mobile source sectors to secondary concentrations of carbonyls

Percentile	5%	25%	50%	75%	95%
Formaldehyde
Air/Rail	0.002	0.005	0.009	0.013	0.022
CMV	0	0.001	0.004	0.057	0.187
Onroad	0.028	0.050	0.072	0.094	0.126
Nonroad	0.009	0.018	0.023	0.033	0.051
Total Mobile	0.058	0.0907	0.118	0.147	0.182
Biogenic	0.299	0.364	0.410	0.483	0.598
Fires	0.004	0.010	0.018	0.028	0.072
Acetaldehyde
Percentile
Air/Rail	−0.012	0.008	−0.005	0.003	−0.001
CMV	−0.051	−0.014	−0.003	−0.001	0.000
Onroad	−0.033	−0.013	−0.002	0.013	0.044
Nonroad	−0.001	0.002	0.009	0.022	0.062
Total Mobile	−0.043	−0.019	0.000	0.027	0.095
Biogenic	0.563	0.689	0.783	0.836	0.900
Fires	0.009	0.023	0.037	0.056	0.118
Acrolein
Percentile
Air/Rail	−0.014	0.002	0.013	0.020	0.041
CMV	−0.307	−0.023	−0.005	−0.002	0.000
Onroad	−0.010	0.109	0.217	0.307	0.419
Nonroad	0.026	0.076	0.112	0.180	0.345
Total Mobile	0.010	0.201	0.355	0.508	0.718
Biogenic	0.051	0.087	0.147	0.206	0.270
Fires	0.087	0.235	0.410	0.636	0.861

Figure 6. Absolute secondary concentration differences (column 1) and percent differences (column 2) from onroad zero out runs for carbonyls (FORM = formaldehyde; ALD2 = acetaldehyde)

Figure 7. Absolute secondary concentration differences (column 1) and percent differences (column 2) from nonroad zero out runs for carbonyls (FORM = formaldehyde; ALD2 = acetaldehyde)

Figure 8. Absolute concentration differences from onroad and nonroad zero out runs for 1,3-butadiene, acrolein precursor