Meteorological Institute, Ludwig-Maximilians-Universität München, Munich, Germany.
Meteorological Institute, Ludwig-Maximilians-Universität München, Munich, Germany.
Sci Total Environ. 2018 Apr 1;619-620:1545-1556. doi: 10.1016/j.scitotenv.2017.10.153. Epub 2017 Oct 21.
In this paper, we present long term observations of atmospheric aerosols and nitrogen dioxide (NO) in Hong Kong using a Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) instrument. Ground based MAX-DOAS measurements were performed over 5years from December 2010 to November 2015. Vertical distribution profiles of aerosols and NO were derived from MAX-DOAS O and NO observations by applying the optimal estimation method. Retrieved MAX-DOAS measurements of aerosols and NO show good agreement with sun photometer observation of aerosol optical depths (AODs) and long path DOAS measurement of ground level NO mixing ratios. Tropospheric vertical column densities (VCDs) of NO derived from MAX-DOAS measurements are used to validate OMI satellite NO observations. Daily data show reasonably good agreement with each other with Pearson correlation coefficient R=0.7. However, MAX-DOAS NO VCDs are on average higher than OMI observations by a factor of 2. Introducing aerosols in the air mass factor calculation would enhance the OMI VCDs by 7-13%, the remaining discrepancy is mainly due to the differences in spatial coverage between the two instruments. Diurnal variation patterns of aerosols and NO indicated significant contributions from local anthropogenic emissions. Analysis of air mass transport shows that the enhancement of surface aerosols and NO concentrations mainly results from accumulation of local emissions under low wind speed conditions.
在本文中，我们使用多轴差分光学吸收光谱（MAX-DOAS）仪器对香港的大气气溶胶和二氧化氮（NO）进行了长期观测。从 2010 年 12 月到 2015 年 11 月，我们进行了为期 5 年的地基 MAX-DOAS 测量。通过应用最佳估计方法，从 MAX-DOAS 的 O 和 NO 观测中推导出了气溶胶和 NO 的垂直分布廓线。从 MAX-DOAS 测量中获取的气溶胶和 NO 的测量值与太阳光度计观测到的气溶胶光学深度（AOD）和长路径 DOAS 测量到的地面 NO 混合比具有很好的一致性。从 MAX-DOAS 测量中得出的 NO 的对流层垂直柱密度（VCD）用于验证 OMI 卫星的 NO 观测结果。每日数据之间具有很好的一致性，皮尔逊相关系数 R=0.7。但是，MAX-DOAS 的 NO VCD 比 OMI 观测值平均高出 2 倍。在大气质量因子计算中引入气溶胶会使 OMI 的 VCD 增加 7-13%，剩余的差异主要是由于这两种仪器的空间覆盖范围不同造成的。气溶胶和 NO 的日变化模式表明，局部人为排放对其浓度有重要贡献。大气传输分析表明，在低风速条件下，当地排放的积累主要导致地表气溶胶和 NO 浓度的增加。
