EGU25-10855, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-10855
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
Retrievals of Stratospheric and Tropospheric Nitrogen Dioxide (NO2) Columns from Satellite Ultraviolet and Visible Spectral Observations
Kai Yang, Zigang Wei, and Lawrence E. Flynn
Kai Yang et al.
  • University of Maryland, AOSC, College Park, MD, United States of America (kaiyang@umd.edu)

Accurate retrieval of tropospheric NO₂ columns relies on precise knowledge of stratospheric NO₂ columns, which can be derived from chemical transport models (CTMs) or estimated through interpolation from regions with minimal tropospheric NO₂ contributions. However, both approaches have their limitations: stratospheric NO₂ fields from CTMs and satellite retrievals often contain biases, and small-scale spatial variations in stratospheric NO₂ can diminish the accuracy of interpolated estimates. These deficiencies can result in significant errors in stratosphere-troposphere separation (STS). In this presentation, we introduce a novel STS approach that combines retrievals from both UV and visible spectra. By leveraging the differing sensitivities of UV and visible wavelengths to tropospheric NO₂, our method provides a more accurate determination of stratospheric and tropospheric NO₂ columns. We will demonstrate the effectiveness of this technique using observations from TROPOMI, GEMS, and TEMPO, showcasing its potential to enhance the accuracy of STS in satellite-based NO₂ retrievals.

How to cite: Yang, K., Wei, Z., and Flynn, L. E.: Retrievals of Stratospheric and Tropospheric Nitrogen Dioxide (NO2) Columns from Satellite Ultraviolet and Visible Spectral Observations, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10855, https://doi.org/10.5194/egusphere-egu25-10855, 2025.