| 天津市PM2.5-O3复合污染特征及气象影响分析 |
| 摘要点击 2215 全文点击 715 投稿时间：2021-10-17 修订日期：2021-11-15 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 天津 PM2.5 臭氧(O3) 复合污染 气象因素 |
| 英文关键词 Tianjin PM2.5 ozone(O3) compound pollution meteorological factors |
|
| 中文摘要 |
| 为了解天津市PM2.5-O3复合污染特征及气象成因，基于2013~2019年高时间分辨率的PM2.5、O3和气象观测数据，对天津市PM2.5-O3复合污染特征、污染物浓度分布以及关键气象因子进行分析.结果表明，2013~2019年，天津市复合污染日94 d，总体呈现下降趋势，前期（2013~2015年）下降明显，由2013年的23 d降至2015年的11 d，下降52.2%；后期（2016~2019年）波动式上升，由2016年的12 d升至2019年的14 d，上升16.7%.复合污染日主要出现在每年的3~9月，年际变化较大，2013~2016年在6~8月出现较多，2017~2019年在4月和9月出现较多.小时ρ（PM2.5）在75~85μg·m-3时，小时ρ（O3）存在峰值区（301~326μg·m-3）.在所有O3污染中，PM2.5-O3复合污染占比平均值为34.4%，并呈逐年减少的趋势.PM2.5-O3复合污染时O3浓度峰值和浓度平均值较单O3污染时高，复合污染日以PM2.5为首要污染物的天数明显减少，以O3为首要污染物的天数逐年增加.天津市PM2.5-O3复合污染的天气形势主要分为低压、弱高压、高压后部、冷锋前和均压场这5种天气类型，其中低压、冷锋前和弱高压为主要天气类型，占总天气类型的92.5%.当风向以西南-南风为主，风速平均值低于2 m·s-1，温度区间为20~35℃，相对湿度区间为40%~60%时，PM2.5-O3复合污染发生概率高. |
| 英文摘要 |
| The characteristics, pollutant concentration distribution, and key meteorological factors of PM2.5-O3 compound pollution in Tianjin were analyzed based on the high-resolution online monitoring data of PM2.5, O3,and meteorological data observed in Tianjin from 2013 to 2019. Total PM2.5-O3 compound pollution was 94 days and showed a decreasing trend by year; a significant decreasing trend of PM2.5-O3 compound pollution days were observed in the early stage, with a decline rate of 52.2% from 2013 to 2015. By contrast, in the later period from 2016 to 2019, a fluctuating increasing trend of PM2.5-O3 compound pollution days of 16.7% was observed. PM2.5-O3 compound pollution days mainly occurred from March to September each year with substantial variation by year, mainly occurring in June to August from 2013 to 2016 and in April and September from 2017 to 2019. The peak value of ρ(O3) (301-326 μg·m-3) appeared when ρ(PM2.5) ranged from 75 μg·m-3 to 85 μg·m-3. PM2.5-O3 compound pollution days accounted for 34.4% of total O3 pollution events in Tianjin, which showed a decreasing trend by year. The peak O3 concentration and average O3 concentration during PM2.5-O3 compound pollution were higher than those during simplex O3 pollution, and the number of days with PM2.5 and O3 as the primary pollutant decreased and increased in compound pollution days by year, respectively. The weather situation of PM2.5-O3 compound pollution was categorized into five weather types, namely low pressure, weak high pressure, rear of high pressure, front of cold front, and equalized pressure. The low pressure, front of cold front, and weak high pressure were observed most frequently, accounting for 92.5% of the total weather situation. The occurrence of PM2.5-O3 compound pollution was most probable when the dominant wind direction was the southwest and south, the average wind speed was less than 2 m·s-1, the temperature was between 20-35℃, and the humidity was between 40%-60%. |
|
|
|
