表 3.
2014—2017年兰州市臭氧浓度不同度量方式的描述性分析
Descriptive statistics for different ozone metrics in Lanzhou during 2014 to 2017
| Category | x±s | Minimum | Percentile | Maximum | ||
| P 25 | P 25 | P 25 | ||||
| O3max1h, the maximum 1 h daily concentration; O38h, the maximum 8 h daily concentration; O324h, the mean 24 h daily concentration. | ||||||
| O3max1h/(μg/m3) | 77.59±33.44 | 15.00 | 57.20 | 69.40 | 82.40 | 252.60 |
| Spring | 83.38±33.80 | 36.50 | 62.00 | 72.60 | 86.90 | 197.80 |
| Summer | 87.28±41.93 | 28.40 | 63.20 | 71.00 | 87.50 | 252.60 |
| Autumn | 73.15±28.77 | 15.00 | 54.40 | 68.00 | 82.80 | 195.20 |
| Winter | 66.29±21.59 | 15.80 | 52.20 | 62.00 | 77.20 | 158.60 |
| O38h/(μg/m3) | 84.03±36.53 | 8.00 | 56.00 | 78.00 | 106.00 | 221.00 |
| Spring | 99.23±32.82 | 20.00 | 78.00 | 98.00 | 118.00 | 221.00 |
| Summer | 104.43±39.93 | 10.00 | 76.00 | 103.00 | 134.00 | 197.00 |
| Autumn | 72.02±29.93 | 8.00 | 51.00 | 67.00 | 87.00 | 182.00 |
| Winter | 59.94±19.88 | 15.00 | 46.00 | 58.00 | 71.00 | 140.00 |
| O324h/(μg/m3) | 38.70±19.97 | 4.94 | 24.52 | 33.96 | 48.31 | 126.11 |
| Spring | 44.81±20.36 | 14.30 | 29.18 | 40.60 | 56.59 | 116.26 |
| Summer | 48.36±22.78 | 17.23 | 32.22 | 40.61 | 56.21 | 126.11 |
| Autumn | 31.42±14.5 | 8.03 | 20.75 | 28.51 | 38.01 | 84.56 |
| Winter | 29.91±13.74 | 4.94 | 19.17 | 26.96 | 38.25 | 78.58 |