Ozone as a Function of Local Wind Speed and Direction: Evidence of Local and Regional Transport Rudolf B. Husar and Wandrille P. Renard CAPITA, Center for Air Pollution Impact and Trend Analysis Washington University St. Louis, Missouri. Background.
Ozone as a Function of Local Wind Speed and Direction: Evidence of Local and Regional TransportRudolf B. Husar and Wandrille P. RenardCAPITA, Center for Air Pollution Impact and Trend Analysis Washington University St. Louis, Missouri
Atmospheric conditions can exert a powerful influence on the distribution of pollutant concentrations in space and time.
Low wind speeds lead to the buildup of high local pollutant concentrations.
Strong ventilation with high wind speeds prevents the local build-up near the sources, but contributes to long-range transport and regional ozone particularly during directionally persistent wind conditions.
In this work, the dependence of ozone concentration on transport is analyzed by classifying the existing ozone concentration data into wind direction and wind speed bins, followed by concentration averaging in each bin.
Average ozone concentration at intermediate (3-6 m/s) wind speed. a) 0-90 degrees. b) 90-180 degrees c) 180-270 degrees d) 270-360 degrees
Relative decline of ozone concentrations with wind speed at different metropolitan areas. Strong decline indicates the influence of local sources, while weak decline suggests transported ozone