2017年10月海南省一次臭氧污染特征及输送路径与潜在源区分析

为了探讨2017年10月海南省一次O₃污染过程的气流轨迹、输送路径和潜在源区，采用海南省18个市县的AQI值、6类大气污染物质量浓度资料以及相关气象观测资料，结合HYSPLIT后向轨迹模型进行分析.结果表明:①2017年10月海南省有13个市县首要污染物为O₃的天数比例超过80%，其中9个市县达100%.2017年10月26日澄迈县和儋州市AQI值分别为171和151，均达中度污染等级，7个市县达轻度污染等级.②气象要素与AQI和污染物质量浓度之间均存在较好的相关关系，ρ(O₃)、AQI与相对湿度的相关系数分别为-0.701和-0.685，均通过了99.9%的信度检验.③卫星反演结果表明，此次污染过程与外源输送关系密切.影响气流主要来自内陆地区的长距离气流、中短距离气流和来自东南沿海的中短距离气流，三支气流影响时段对应的海口市AQI值分别为83、69和61，对应的ρ(O₃)分别为和135.0、119.6和102.3 μg/m3.④通过计算PSCF(潜在源贡献因子)和CWT(浓度权重轨迹)发现，广东省为海南省的主要潜在贡献源区，湖南省、江西省、江苏省、浙江省和福建省等地区也有一定的潜在贡献.研究显示，2017年10月海南省出现的O₃污染过程中，污染物来源以外源输送为主. 

Potential Source Contributions and Transported Routes in Hainan Province during Ozone Polluted Episode in October 2017

This study investigates the airflow trajectory, transport path and potential source region of the ozone pollution event occurred in Hainan Province in October 2017 using AQI values and the concentrations of 6 atmospheric pollutants from meteorological observation data as well as the backward trajectory model (HYSPLIT). The results indicated that: (1) The days of main pollutant O₃ concentration in 13 cities exceeded more than 80% of the period, and the days in 9 cities reached 100%. On October 26th, the AQI values in Chengmai County and Dangzhou City reached moderate pollution levels of 171 and 151, respectively. In addition, 7 cities reached a mild pollution level. (2) There was a good correlation between meteorological elements, AQI and pollutant concentration. The correlation coefficients between ρ(O₃) and AQI and relative humidity were -0.701 and -0.685, respectively, and passed the 99.9% significance test. (3) Satellite inversion indicated that exogenous transport had a direct impact on this pollution episode. The impacted airflows included long-distance airflows from inland, medium- and short-distance airflows from inland and short-distance airflows from the southeast coast. The corresponding AQI values of Haikou were 83, 69 and 61, and the corresponding ρ(O₃) were 135.0, 119.6 and 102.3 μg/m3 during the three airflow impact periods, respectively. (4) The potential source contribution factor (PSCF) and concentration weight trajectory (CWT) indicated that Guangdong Province was the main potential contribution region for this pollution episode. Besides, Hunan Province, Jiangxi Province, Jiangsu Province, Zhejiang Province and Fujian Province also had certain potential contributions. Overall, the pollutants that occurred in Hainan Province in October 2017 were mainly from exogenous O₃ pollution sources.