Table 1.
Means and standard deviations over a six-year period of different exposure metrics calculated from simulated monitor data central monitor (CM), unweighted average (UA), population-weighted average (PWA), and area-weighted average (AWA) and of the true population-weighted average (TPWA) calculated from the simulated true ambient concentration field. Standard deviations for results of 10 independent sets of CO simulations are shown.
| pollutant | CM | UA | PWA | AWA | TPWA | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| mean | st dev | mean | st dev | mean | st dev | mean | st dev | mean | st dev | |
| NO2 (ppb) | 44.5 | 20.3 | 29.4 | 12.6 | 23.5 | 11.5 | 15.4 | 8.8 | 24.7 | 10.4 |
| NOx (ppm) | 0.117 | 0.118 | 0.065 | 0.057 | 0.046 | 0.041 | 0.025 | 0.021 | 0.052 | 0.042 |
| CO (ppm) | 1.58 ± 0.02 | 1.31 ± 0.06 | 1.07 ± 0.02 | 0.69 ± 0.04 | 0.75 ± 0.01 | 0.42 ± 0.02 | 0.45 ± 0.01 | 0.20 ± 0.01 | 0.72 ± 0.03 | 0.34 ± 0.04 |
| SO2 (ppb) | 14.0 | 22.8 | 12.8 | 12.3 | 10.3 | 10.6 | 8.9 | 7.9 | 12.2 | 8.56 |
| O3 (ppb) | 44.9 | 27.9 | 44.8 | 23.0 | 43.9 | 23.0 | 44.1 | 20.0 | 44.6 | 24.6 |
| PM10 (μg/m3) | 25.1 | 14.9 | 24.0 | 13.1 | 22.6 | 13.1 | 21.2 | 12.5 | 23.0 | 12.4 |
| PM2.5 (μg/m3) | 18.0 | 10.0 | 17.0 | 8.9 | 16.1 | 8.9 | 11.0 | 8.9 | 16.1 | 8.49 |
| SO42− (μg/m3) | 5.35 | 5.29 | 5.03 | 4.67 | 4.93 | 4.71 | 4.67 | 4.33 | 4.96 | 4.54 |
| NO3− (μg/m3) | 1.34 | 1.56 | 1.15 | 1.23 | 1.11 | 1.19 | 1.01 | 1.07 | 1.13 | 1.18 |
| NH4+ (μg/m3) | 2.32 | 1.85 | 2.34 | 1.72 | 2.24 | 1.72 | 2.22 | 1.64 | 2.30 | 1.70 |
| EC (μg/m3) | 0.90 | 0.88 | 0.70 | 0.54 | 0.62 | 0.49 | 0.50 | 0.38 | 0.68 | 0.50 |
| OC (μg/m3) | 5.93 | 4.29 | 5.33 | 3.31 | 5.10 | 3.28 | 4.69 | 2.90 | 5.16 | 3.15 |