Table 2.
Summary statistics for daily weather conditions and air pollutants in Guangzhou, China, 2003 to 2012
| Variables | Frequency distribution | Mean | SD | ||||
|---|---|---|---|---|---|---|---|
| Min | 25 % | Median | 75 % | Max | |||
| Mean temperature (°C) | 5.1 | 18.2 | 24.2 | 27.7 | 34.2 | 22.6 | 6.3 |
| Case periods | 5.4 | 18.9 | 24.5 | 27.9 | 34.2 | 23.0 | 6.1 |
| Control periods | 5.1 | 18.5 | 24.7 | 27.9 | 34.2 | 22.9 | 6.3 |
| Relative humidity (%) | 20.0 | 65.0 | 74.0 | 82.0 | 99.0 | 72.4 | 13.0 |
| Case periods | 22.0 | 65.0 | 75.0 | 82.0 | 99.0 | 73.2 | 12.5 |
| Control periods | 23.0 | 66.0 | 75.0 | 82.0 | 99.0 | 72.8 | 13.0 |
| Atmospheric pressure (hpa) | 987.4 | 1002.5 | 1007.4 | 1013.0 | 1027.2 | 1007.7. | 7.0 |
| Case periods | 987.4 | 1 001.9 | 1 006.8 | 1 012.7 | 1 025.2 | 1 007.2 | 7.1 |
| Control periods | 987.4 | 1 002.1 | 1 006.9 | 1 012.8 | 1 027.2 | 1 007.3 | 7.0 |
| Sunshine duration (hours) | 0.0 | 0.3 | 4.1 | 7.8 | 11.8 | 4.3 | 3.6 |
| Case periods | 0.0 | 0.3 | 3.9 | 7.6 | 11.8 | 4.2 | 3.6 |
| Control periods | 0.0 | 0.2 | 4.0 | 7.7 | 11.8 | 4.3 | 3.6 |
| PM10 (μg/m3) | 7.0 | 48.3 | 70.6 | 100.6 | 370.1 | 79.6 | 43.8 |
| Case periods | 7.0 | 48.6 | 71.7 | 103.6 | 370.1 | 81.2 | 44.2 |
| Control periods | 7.0 | 48.0 | 70.4 | 99.4 | 370.1 | 78.9 | 42.4 |
| SO2 (μg/m3) | 2.3 | 21.4 | 37.1 | 60.9 | 237.3 | 46.3 | 34.3 |
| Case periods | 3.0 | 23.1 | 38.5 | 64.6 | 226.1 | 48.3 | 35.3 |
| Control periods | 2.3 | 21.3 | 36.4 | 60.1 | 237.3 | 46.1 | 34.6 |
| NO2 (μg/m3) | 16.7 | 43.2 | 57.8 | 78.8 | 281.3 | 65.3 | 30.4 |
| Case periods | 16.7 | 43.7 | 59.4 | 79.9 | 254.7 | 66.6 | 31.3 |
| Control periods | 16.7 | 43.0 | 57.7 | 77.7 | 281.3 | 64.5 | 29.5 |