Articles online

Meteorological Influences on Tropospheric Ozone over Suburban Washington, DC

Category: Urban Air Quality

Volume: 18 | Issue: 5 | Pages: 1168-1182
DOI: 10.4209/aaqr.2017.12.0574

Export Citation:  RIS | BibTeX

Mayra I. Oyola 1, Anna Schneider2, James Campbell3, Everette Joseph4

  • 1 American Society for Engineering Education /Naval Research Laboratory, Monterey, CA 93940, USA
  • 2 NOAA National Weather Service, San Francisco Bay Area, CA 93943-5005, USA
  • 3 Naval Research Laboratory, Monterey, CA 93943, USA
  • 4 University at Albany, State University of New York, Albany, NY 12222, USA


Weather is main driver of O3 variability within atmospheric column.
Stratospheric intrusion mostly responsible for high O3 in the mid/upper troposphere.
Horizontal advection and aged air masses account for over 40% of the total O3 budget.
A combined effect of storms and high pressure led to 70% O3 decrease in the column.


During the NASA DISCOVER-AQ (Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality) campaign conducted in July 2011 across metropolitan Washington, DC, 25 daytime ozonesondes were launched from the Howard University Beltsville Campus (HUBC), representing the highest temporal density of measurements ever taken over the region. Time-height depiction of ozone concentration reveals considerable variability near the surface and in the mid/upper troposphere. Meteorological influences are assessed using the synoptic and mesoscale information, which revealed that periodic stratospheric intrusion of ozone-rich air was the main mechanism for elevated levels in the upper troposphere. It is also shown that high concentrations of ozone prevalent in the free troposphere were due to a combination of advection and aged air masses, which accounted for over 40% of the total budget. Poor air quality episodes with high surface concentration were due local emissions of precursors and associated synoptic-scale conditions. Breaks in the elevated ozone concentrations in the boundary layer and free troposphere occurred from frontal passages and accompanying storms. In the most unusual case (26 July, 2011), the combined effect of storms followed by two frontal passages and high pressure positioned west of the region led to decrease column ozone as much as 70%. The unusually deep extent of the reduction appears to be related to the temporary cutoff of air advected from fire locations and polluted regions, which dominated the upper troposphere throughout the period.


Tropospheric ozone Stratospheric injections Laminar analysis Meteorological influence on ozone NASA DISCOVER-AQ Beltsville MD

Related Article

Consistency of Urban Background Black Carbon Concentration Measurements by Portable AE51 and Reference AE22 Aethalometers: Effect of Corrections for Filter Loading

Nicola Masey, Eliani Ezani, Jonathan Gillespie, Fiona Sutherland, Chun Lin, Scott Hamilton, Mathew R. Heal, Iain J. Beverland
Accepted Manuscripts
DOI: 10.4209/aaqr.2019.03.0145