海口市臭氧污染及气象条件特征

近年来,臭氧已成为许多城市环境空气的主要污染物之一。笔者分析了2020年海口市5个不同方位代表性监测站点逐小时空气质量监测数据及对应站点的气象要素监测数据。研究结果表明:海口市2020年环境空气污染程度为三级以上的天数有11d,其首要污染物均为臭氧。臭氧浓度高值时段主要出现在10-12月。浓度最大值主要出现在每日14:00-17:00,最小值出现在每日05:00-08:00。气象要素日均值与臭氧浓度相关性大小依次为最高温度＞平均温度＞相对湿度＞降水量＞日照时数＞风速。台风外围下沉气流和东北气流的共同影响是导致海口市臭氧浓度超标的主要因素,下沉气流更有利于低层大气中臭氧的堆积,同时在东北气流影响下,上游区域污染物的传输也会导致海口市臭氧浓度增加。

Characteristics of Ozone Pollution and Meteorological Conditions in Haikou City

In recent years,ozone pollution has become one of the main pollutants of air pollution in many cities of China.In this paper,hourly air quality monitoring data from 5 representative monitoring sites in Haikou City in 2020 and the corresponding site meteorological element monitoring data were used for research and analysis.The results showed that the numbers above third-level days were 11 days in Haikou City in 2020,and the primary pollutant was ozone.The period of high ozone concentration mainly occurred from October to December.The maximum of O₃-8 h occurs time period mainly occurred at 14:00-17:00,and the lowest value occurred at 05:00-08:00.Correlation analysis between the daily mean value of meteorological elements and O₃-8 h was highest temperature>average temperature>relative humidity>precipitation>sunshine hours>wind speed.The downdraft and northeast airflow around the typhoon were one of the main factors that caused the ozone concentration in Haikou to exceed the standard.The sinking airflow was more conducive to the accumulation of ozone concentration in the lower atmosphere.Under the action of the northeast airflow,the transmission of pollutants from the northeast to the region was also one of the main factors leading to the increase in ozone concentration in Haikou.