Articles | Volume 19, issue 13
https://doi.org/10.5194/acp-19-8863-2019
https://doi.org/10.5194/acp-19-8863-2019
Research article
 | 
12 Jul 2019
Research article |  | 12 Jul 2019

Using satellite observations of tropospheric NO2 columns to infer long-term trends in US NOx emissions: the importance of accounting for the free tropospheric NO2 background

Rachel F. Silvern, Daniel J. Jacob, Loretta J. Mickley, Melissa P. Sulprizio, Katherine R. Travis, Eloise A. Marais, Ronald C. Cohen, Joshua L. Laughner, Sungyeon Choi, Joanna Joiner, and Lok N. Lamsal

Related authors

Effect of changing NOx lifetime on the seasonality and long-term trends of satellite-observed tropospheric NO2 columns over China
Viral Shah, Daniel J. Jacob, Ke Li, Rachel F. Silvern, Shixian Zhai, Mengyao Liu, Jintai Lin, and Qiang Zhang
Atmos. Chem. Phys., 20, 1483–1495, https://doi.org/10.5194/acp-20-1483-2020,https://doi.org/10.5194/acp-20-1483-2020, 2020
Short summary
Inconsistency of ammonium–sulfate aerosol ratios with thermodynamic models in the eastern US: a possible role of organic aerosol
Rachel F. Silvern, Daniel J. Jacob, Patrick S. Kim, Eloise A. Marais, Jay R. Turner, Pedro Campuzano-Jost, and Jose L. Jimenez
Atmos. Chem. Phys., 17, 5107–5118, https://doi.org/10.5194/acp-17-5107-2017,https://doi.org/10.5194/acp-17-5107-2017, 2017
Short summary

Related subject area

Subject: Gases | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Contributions of lightning to long-term trends and inter-annual variability in global atmospheric chemistry constrained by Schumann resonance observations
Xiaobo Wang, Yuzhong Zhang, Tamás Bozóki, Ruosi Liang, Xinchun Xie, Shutao Zhao, Rui Wang, Yujia Zhao, and Shuai Sun
Atmos. Chem. Phys., 25, 8929–8942, https://doi.org/10.5194/acp-25-8929-2025,https://doi.org/10.5194/acp-25-8929-2025, 2025
Short summary
Climate-driven biogenic emissions alleviate the impact of human-made emission reductions on O3 control in the Pearl River Delta region, southern China
Nan Wang, Song Liu, Jiawei Xu, Yanyu Wang, Chun Li, Yuning Xie, Hua Lu, and Fumo Yang
Atmos. Chem. Phys., 25, 8859–8870, https://doi.org/10.5194/acp-25-8859-2025,https://doi.org/10.5194/acp-25-8859-2025, 2025
Short summary
Impacts of wildfire smoke aerosols on near-surface ozone photochemistry
Jiaqi Shen, Ronald C. Cohen, Glenn M. Wolfe, and Xiaomeng Jin
Atmos. Chem. Phys., 25, 8701–8718, https://doi.org/10.5194/acp-25-8701-2025,https://doi.org/10.5194/acp-25-8701-2025, 2025
Short summary
Natural surface emissions dominate anthropogenic emissions contributions to total gaseous mercury at Canadian rural sites
Irene Cheng, Amanda Cole, Leiming Zhang, and Alexandra Steffen
Atmos. Chem. Phys., 25, 8591–8611, https://doi.org/10.5194/acp-25-8591-2025,https://doi.org/10.5194/acp-25-8591-2025, 2025
Short summary
Modelling Arctic lower-tropospheric ozone: processes controlling seasonal variations
Wanmin Gong, Stephen R. Beagley, Kenjiro Toyota, Henrik Skov, Jesper Heile Christensen, Alex Lupu, Diane Pendlebury, Junhua Zhang, Ulas Im, Yugo Kanaya, Alfonso Saiz-Lopez, Roberto Sommariva, Peter Effertz, John W. Halfacre, Nis Jepsen, Rigel Kivi, Theodore K. Koenig, Katrin Müller, Claus Nordstrøm, Irina Petropavlovskikh, Paul B. Shepson, William R. Simpson, Sverre Solberg, Ralf M. Staebler, David W. Tarasick, Roeland Van Malderen, and Mika Vestenius
Atmos. Chem. Phys., 25, 8355–8405, https://doi.org/10.5194/acp-25-8355-2025,https://doi.org/10.5194/acp-25-8355-2025, 2025
Short summary

Cited articles

Air Sciences: 2002 Fire Emission Inventory for the WRAP Region – Phase II, Denver and Portland, 2005. 
Amedro, D., Bunkan, A. J. C., Berasategui, M., and Crowley, J. N.: Kinetics of the OH+NO2 reaction: Rate coefficients (217–333 K, 16–1200 mbar) and fall-off parameters for N2 and O2 bath-gases, Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2019-297, in review, 2019. 
Anderson, D. C., Loughner, C. P., Diskin, G., Weinheimer, A., Canty, T. P., Salawitch, R. J., Worden, H. M., Fried, A., Mikoviny, T., Wisthaler, A., and Dickerson, R. R.: Measured and modeled CO and NOy in DISCOVER-AQ: An evaluation of emissions and chemistry over the eastern US, Atmos. Environ., 96, 78–87, https://doi.org/10.1016/j.atmosenv.2014.07.004, 2014. 
Anderson, J. G., Weisenstein, D. K., Bowman, K. P., Homeyer, C. R., Smith, J. B., Wilmouth, D. M., Sayres, D. S., Klobas, J. E., Leroy, S. S., Dykema, J. A., and Wofsy, S. C.: Stratospheric ozone over the United States in summer linked to observations of convection and temperature via chlorine and bromine catalysis, P. Natl. Acad. Sci. USA, 114, E4905–E4913, https://doi.org/10.1073/pnas.1619318114, 2017. 
Anderson, J. G., Clapp, C. E., Bowman, K. P., Homeyer, C. R., Weisenstein, D. K., Smith, J. B., Wilmouth, D. M., and Klobas, J. E.: Coupling Free Radical Catalysis, Convective Injection into the Stratosphere, Climate Forcing, and Human Health, AMS Annual Meeting, Phoenix, AZ, 2019. 
Download
Short summary
The US EPA reports a steady decrease in nitrogen oxide (NOx) emissions from fuel combustion over the 2005–2017 period, while satellite observations show a leveling off after 2009, suggesting emission reductions and related air quality gains have halted. We show the sustained decrease in NOx emissions is in fact consistent with observed trends in surface NO2 and ozone concentrations and that the flattening of the satellite trend reflects a growing influence from the non-anthropogenic background.
Share
Altmetrics
Final-revised paper
Preprint