海口市空气质量的特征及其与气象条件的关系

Relationship between the Air Quality Status of Haikou and Meteorological Conditions

根据海口市2013—2014年空气污染物的监测数据及气象资料,研究了该市的空气质量特征及其与气象要素的关系.结果表明:海口市空气质量优良率为95%;PM_(2.5),PM_(10),O_3是该市的主要污染物,年均质量浓度分别为25.29μg·m^(-3),44.48μg·m^(-3),77.15μg·m^(-3);该市的空气质量随季节变化的特征明显,春、夏、秋、冬四季的AQI值分别为42,35,54,65;污染物的"周末效应"与北京、深圳等国内其他城市不同,表现为:周末浓度大于工作日浓度;旅游黄金周期间污染物均有不同程度增加;污染物日变化特征明显;SO_2,PM_(2.5)表现出一定的区域污染特征;NO_2,PM_(10),CO和O_3表现出一定的局部污染特征;降水、风速、风向、温度、湿度对空气质量的影响显著,在多数情况下AQI与降水、风速、温度、湿度等存在负相关,而与气压存在正相关;对典型污染过程的分析表明:PM_(2.5)受扩散条件、本地排放及外地输送共同影响,O_3浓度与蒸发量、相对湿度及风速等指标有明显关系.

In the study, the monitoring data of air pollutants and meteorological data of Haikou during 2013 - 2014 were used to analyze the relationship between the air quality characteristics and meteorological elements. The results indicated that the excellent and good rate of the air quality of Haikou reach 95%. PM2.5, PM10, and 03 were the major pollutants with an annual average concentration of 25.29 μg·m-3 44.48 μg·m-3 and 77.15 μg·m-3, respectively. The seasonal change characteristic of the air quality was obvious, and the AQI of spring, summer, autumn, and winter were 42, 35, 54 and 65 respectively. The concentration of pollu- tants at the weekend was greater than that at the working days, and the ＂weekend effects＂ was different from that of other domestic cities including Beijing and Shenzhen. Each pollutant increased in different degrees during the Tourism Golden Weeks. The daily variation characteristics of pollutants was obvious. SO2 ,PM25 showed some regional pollution characteristics, while NO2 ,PM10,CO, and O3 showed some atmospheric pollution characteris- tics. The air quality was significantly influenced by precipitation, wind speed and direction, temperature and hu- midity. In most cases, there were negative correlations between AQI and precipitation, temperature, humidity and wind speed, whereas there was positive correlation between AQI and air pressure. The results of the typical pollution process analysis showed that PM2.5 was influenced by diffusion conditions, local emissions and overseas delivery together, and there were obvious relationships between O3 concentration and evaporation, relative humidity and wind velocity, respectively.