2016—2017年冬春季海南3市气溶胶质量浓度特征对比分析

利用2016年12月至2017年5月海南省3个地级市（三沙市永兴岛、三亚、海口）监测的PM_2.5、PM₁₀数据，对比分析其污染特征。结果表明：相较于海口、三亚，永兴岛空气质量最好，细粒子污染程度最轻且PM_2.5、PM₁₀质量浓度日变化最平稳，其主要原因是人类生产活动对空气质量的影响不大。进一步通过分析3个站点的PM_2.5质量浓度与近地面气象要素（相对湿度、月总降水量、能见度）发现，永兴岛PM_2.5质量浓度与能见度整体呈负相关，永兴岛在不同风速、风向上的PM_2.5质量浓度最小，三亚次之，海口最大。永兴岛PM_2.5的大值区主要出现在东北风向上，其他方向上的气流则相对比较清洁，且在静风或者微风条件下，永兴岛的初始PM_2.5质量浓度比较低。通过每天逐6 h的72 h后向轨迹分析发现，冬季、夏季风影响期间，永兴岛分别受来源于西太平洋、南海的海洋性气流影响，这与永兴岛的空气质量有直接关系。

Comparative analysis of aerosol mass concentration characteristics in winter and spring during 2016 to 2017 in three cities of Hainan province

Based on comparative analysis of the monitoring data of PM_2.5 and PM₁₀ of three cities from Hainan province (Yongxing Island, Sanya and Haikou) from December of 2016 to May of 2017, the pollution characteristics in Yongxing Island were analyzed.The results show that, compared with Haikou and Sanya, Yongxing Island has the best air quality, the lightest fine particle pollution and the most stable daily variation of PM_2.5 and PM₁₀ mass concentrations.The main reason is that human production activities have little impact on air quality.Through further analysis of PM_2.5 mass concentrations of the three stations and near-surface meteorological elements (relative humidity, total monthly precipitation and visibility), it is found that the PM_2.5 mass concentration of Yongxing Island is negatively correlated with visibility as a whole, and the PM_2.5 mass concentration of Yongxing Island is the lowest at different wind speeds and winds, followed by Sanya and Haikou.The large PM_2.5 concentration area of Yongxing Island mainly appears in the upward direction of the northeast wind, while the air flow in the other directions is relatively clean.Moreover, the initial PM_2.5 mass concentration of Yongxing Island is relatively low under the conditions of calm wind or light wind.By analyzing the 72-hour backward trajectory six hours a day, it is found that during the winter and summer monsoon, Yongxing Island is respectively affected by the Marine air currents originating from the western Pacific Ocean and the South China Sea, which are directly related to the air quality of Yongxing Island.