Table 1.
Summary by site type in England, Scotland, Wales, and Northern Ireland.
| Site Type | 5-week average daily concentrations, covering April 2020 in μg/m3 (AURN count)a |
% change on the 5-week average daily concentration measured in 2017–19a |
Absolute change on the 5-week average daily concentration measured in 2017–19 (μg/m3)a |
% days below the 5-week average daily concentration in 2017–19 |
||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| NO2 | NOX | O3 | PM2.5 | NO2 | NOX | O3 | PM2.5 | NO2 | NOX | O3 | PM2.5 | NO2 | NOX | O3 | PM2.5 | |
| Rural Background | 5.7 (9) | 10.1 (11) | 73.7 (16) | 11.5 (3) | −23.9 | +17.5 | +0.1 | −2.6 | −1.8 | +1.5 | +0.1 | −0.3 | 78.4 | 73.5 | 48.9 | 67.6 |
| Suburban Background | 15.0 (3) | 18.5 (3) | 68.1 (2) | 14.5 (2) | −14.8 | −18.6 | −0.4 | −12.0 | −2.6 | −4.2 | −0.3 | −2.0 | 71.4 | 76.2 | 52.9 | 72.9 |
| Urban Background | 12.6 (41) | 16.6 (41) | 66.4 (31) | 10.9 (28) | −36.7 | −37.8 | +7.4 | −17.3 | −7.3 | −10.1 | +4.6 | −2.3 | 84.1 | 85.6 | 33.7 | 74.2 |
| Urban Traffic | 17.5 (47) | 30.0 (47) | 57.8 (3) | 10.4 (11) | −47.9 | −57.3 | +34.1 | −18.1 | −16.1 | −40.3 | +14.7 | −2.3 | 93.5 | 95.6 | 11.4 | 75.8 |
| Suburban Industrial | 10.4 (2) | 14.0 (2) | 63.3 (1) | – | −50.5 | −49.6 | +2.9 | – | −10.6 | −13.8 | +1.8 | – | 98.6 | 98.6 | 34.3 | – |
| Urban Industrial |
11.0 (5) |
13.4 (6) |
68.3 (3) |
10.5 (3) |
−30.6 |
−33.3 |
+7.4 |
−15.3 |
−4.9 |
−6.7 |
+4.7 |
−1.9 |
86.2 |
85.6 |
36.2 |
69.5 |
| All Sites | 14.1 (107) | 21.5 (110) | 68.1 (56) | 10.9 (47) | −38.3 | −38.0 | +7.6 | −16.5 | −8.8 | −13.2 | 4.8 | −2.2 | 87.8 | 88.6 | 37.7 | 73.8 |
a
Calculations required at least 95% of the daily-average measurements to be available in (a) weeks 14 to 18 of 2020, and (b) weeks 14 to 18 of 2017-19. Days were excluded from the 5-week average calculations, where less than 18-h of measurement data is available.