基于地基MAX-DOAS在2013年8月—2014年7月对合肥对流层NO2垂直柱浓度(VCD)进行了观测,研究了其季节均值和月均值变化特征,结果表明合肥地区对流层NO2 VCD季节均值变化较大,冬季最大,夏季最小,其中冬季季节均值高达2.09×10(16)mol·cm(-2),为夏季的2.2倍。对不同季节的平均日变化的分析表明,NO2 VCD日变化季节差异显著并在下午达到差异最大值。将地基MAX-DOAS观测结果和OMI观测结果进行了对比,两者具有较好的一致性,其中在无云天气下两者的相关系数为0.88。通过卫星观测获取了合肥以及周边地区的NO2 VCD季节均值,分析表明合肥地区的NO2主要以本地积累为主,外来输送贡献较小。
The tropospheric NO2 vertical column density(VCD)in Hefei area was studied with groud-based MAX-DOAS data from August 2013 to July 2014.It is shown that tropospheric NO2 VCD season mean and month mean values changed greatly.The maximum value was in the winter while the minimum value was in the summer with the season mean value in winter of 2.09×10~(16) mol·cm~(-2) whihc was 2.2times of that in the summer.The research of average diurnal variation in different seasons displayed that biggest discrepancy appeared in the afternoon.Comparison between MAX-DOAS measurements and OMI observations had been conducted and results had an good agreement,especially in cloud-free condition(R~2=0.88).The season mean value of tropospheric NO2 VCD around Hefei area from OMI observation showed that high NO2 in Hefei was mainly from local accumulation instead of transportation.