EGU25-3995, updated on 14 Mar 2025
https://doi.org/10.5194/egusphere-egu25-3995
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
Oral | Friday, 02 May, 12:15–12:25 (CEST)
 
Room M1
Relating satellite NO2 tropospheric columns to near-surface concentrations: implications from ground-based MAX-DOAS NO2 vertical profile observations
Bowen Chang1, Haoran Liu1, Chengxin Zhang2, Chengzhi Xing3, Wei Tan3, Qihua Li1, Xiangguang Ji1, Qihou Hu3, and Cheng Liu2
Bowen Chang et al.
  • 1Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei, 230601, China. (q23101001@stu.ahu.edu.cn, hrl@ahu.edu.cn, lqh628@ahu.edu.cn, xgji@ahu.edu.cn)
  • 2Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230026, China. (zcx2011@ustc.edu.cn, chliu81@ustc.edu.cn)
  • 3Key Lab of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, China. (xingcz@aiofm.ac.cn, wtan@aiofm.ac.cn, qhhu@aiofm.ac.cn)

Given the significant environmental and health risks associated with near-surface nitrogen dioxide (NO2), machine learning is frequently employed to estimate near-surface NO2 concentrations (SNO2) from satellite-derived tropospheric NO2 column densities (CNO2). However, data-driven methods often face challenges in explaining the complex relationships between these variables. In this study, the correlation between CNO2 and SNO2 is examined using vertical profile observations from China’s MAX-DOAS network. Cloud cover and air convection substantially weaken (R = −0.68) and strengthen (R = 0.71) the CNO2-SNO2 correlation, respectively. Meteorological factors dominate the correlation (R2 = 0.58), which is 31% stronger in northern regions than in the southwest. Additionally, anthropogenic emissions impact SNO2, while topographical features shape regional climate patterns. At the Chongqing site, the negative impacts of unfavorable meteorological conditions, high emissions, and basin topography lead to significant contrasts and delays in daily CNO2 and SNO2 variations. This study enhances understanding of the spatial and temporal dynamics and influencing mechanisms of CNO2 and SNO2, supporting improved air quality assessments and pollution exposure evaluations.

How to cite: Chang, B., Liu, H., Zhang, C., Xing, C., Tan, W., Li, Q., Ji, X., Hu, Q., and Liu, C.: Relating satellite NO2 tropospheric columns to near-surface concentrations: implications from ground-based MAX-DOAS NO2 vertical profile observations, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3995, https://doi.org/10.5194/egusphere-egu25-3995, 2025.