Rapid O3 assimilations – Part 2: Tropospheric O3 changes accompanied by declining NOx emissions in the USA and Europe in 2005–2020

Zhu, Rui; Tang, Zhaojun; Chen, Xiaokang; Liu, Xiong; Jiang, Zhe

doi:https://doi.org/10.5194/acp-23-9745-2023

Articles | Volume 23, issue 17

https://doi.org/10.5194/acp-23-9745-2023

© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/acp-23-9745-2023

© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 23, issue 17

Research article

|

01 Sep 2023

Research article |

| 01 Sep 2023

Rapid O₃ assimilations – Part 2: Tropospheric O₃ changes accompanied by declining NO_x emissions in the USA and Europe in 2005–2020

Rui Zhu, Zhaojun Tang, Xiaokang Chen, Xiong Liu, and Zhe Jiang

Supplement

https://doi.org/10.5194/acp-23-9745-2023-supplement

Data sets

Surface O3 measurements EEA (European Environment Agency) https://discomap.eea.europa.eu/map/fme/AirQualityExport.htm

Surface O3 measurements US EPA (Environmental Protection Agency) https://aqs.epa.gov/aqsweb/airdata/download_files.html#Raw

OMI/Aura Vertical Ozone (O3) Profile (PROFOZ) K. Yang, X. Liu, and P. Bhartia https://avdc.gsfc.nasa.gov/pub/data/satellite/Aura/OMI/V03/L2/OMPROFOZ/

Model code and software

KPP module for tagged-O3 simulation Zhe Jiang https://doi.org/10.5281/zenodo.7545944

GEOS-Chem The International GEOS-Chem User Community https://doi.org/10.5281/zenodo.3837666

Short summary

Ozone Monitoring Instrument (OMI) and surface O₃ observations are used to investigate the changes in tropospheric O₃ in the USA and Europe in 2005–2020. The surface-based assimilations show limited changes in surface and tropospheric column O₃. The OMI-based assimilations show larger decreases in tropospheric O₃ columns in 2010–2014, related to a decline in free-tropospheric NO₂. Analysis suggests limited impacts of local emissions decline on tropospheric O₃ over the USA and Europe in 2005–2020.