Table 2.
Daily outdoor levels of PM2.5, its components, and temperature at central measurement sites in three cities.
| Amsterdam (n = 223)
|
Erfurt (n = 156)
|
Helsinki (n = 164)
|
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| p25 | p50 | P75 | p95 | p25 | p50 | p75 | p95 | p25 | p50 | p75 | p95 | |
| PM2.5 (μg/m3) | 10.4 | 16.7 | 23.9 | 47.0 | 10.8 | 16.3 | 26.7 | 62.3 | 8.3 | 10.6 | 15.9 | 25.8 |
| Source-specific PM2.5 (μg/m3) | ||||||||||||
| Local traffic | 3.5 | 6.1 | 9.3 | 20.4 | 4.1 | 7.0 | 10.0 | 18.4 | 1.7 | 2.6 | 3.4 | 6.5 |
| Long-range transported | 0.3 | 5.1 | 11.6 | 21.8 | 3.1 | 5.4 | 9.8 | 31.9 | 2.2 | 5.5 | 9.8 | 15.9 |
| Oil combustion | 0.9 | 1.6 | 3.1 | 5.9 | NA | NA | NA | NA | 0.6 | 1.3 | 2.3 | 4.2 |
| Industry | −2.6 | −0.5 | 3.0 | 9.2 | −3.6 | −1.6 | 2.2 | 24.7 | NA | NA | NA | NA |
| Crustal | 0.7 | 1.4 | 2.1 | 3.6 | 1.8 | 2.7 | 4.8 | 13.8 | 0.0 | 0.4 | 1.1 | 2.2 |
| Salt | 0.1 | 0.2 | 0.8 | 1.8 | NA | NA | NA | NA | 0.3 | 0.8 | 1.2 | 2.4 |
| Absorbance (m−1 × 10−5) | 0.9 | 1.5 | 2.2 | 3.4 | 1.3 | 2.0 | 3.4 | 5.1 | 1.4 | 1.89 | 2.47 | 3.56 |
| Elements (ng/m3) | ||||||||||||
| S | 936 | 1,340 | 2,240 | 3,650 | 600 | 862 | 1,530 | 3,740 | 839 | 1,380 | 2,080 | 3,400 |
| V | 2.5 | 4.1 | 7.8 | 14.7 | NA | NA | NA | NA | 3.2 | 6.69 | 9.8 | 16.4 |
| Zn | 8.7 | 18.2 | 33.9 | 65.2 | 22.6 | 40.2 | 75.1 | 199 | 11.3 | 16.8 | 25.1 | 47.3 |
| Ca | 26.9 | 37.1 | 51.8 | 76.9 | 34.6 | 47.0 | 72.2 | 193 | 22.7 | 32.3 | 47.3 | 87.0 |
| Cl | 33.8 | 116 | 432 | 990 | NA | NA | NA | NA | 8.1 | 36.4 | 102 | 386 |
| Fe | 47.1 | 70.7 | 107 | 175 | 38.6 | 59.9 | 112 | 248 | 39.3 | 66.7 | 100 | 165 |
| Cu | 1.4 | 2.5 | 4.7 | 9.0 | 0.6 | 2.5 | 4.9 | 10.4 | 0.6 | 1.6 | 2.8 | 5.1 |
| Temperature (°C) | 4.4 | 7.9 | 12.3 | 16.9 | −0.1 | 3.9 | 6.7 | 11.2 | −5.0 | −0.6 | 2.5 | 8.8 |
Abbreviations: NA, not available; p25, 25th percentile; p50, 50th percentile (median); p75, 75th percentile; p95, 95th percentile.