Ground-level ozone is a harmful air pollutant associated with several health issues. Ozone concentrations have exceeded the National Ambient Air Quality Standards (NAAQS) in the Chicago metropolitan area on hot summer...Ground-level ozone is a harmful air pollutant associated with several health issues. Ozone concentrations have exceeded the National Ambient Air Quality Standards (NAAQS) in the Chicago metropolitan area on hot summer days for many years because of nitrogen oxide and volatile organic compound emissions. Annual fourth highest 8-hour ozone concentrations have been between 0.070 and 0.084 ppm at several monitoring sites in Cook county, during the 2016-2018 time period. The continuous measurement of nitrogen dioxide (NO<sub>2</sub>) and ozone (O<sub>3</sub>) was conducted in several communities in Chicago in 2017. The air pollution impacts the health of all who live in the area. The data were used to analyze correlations between the O<sub>3</sub> distribution and its association with ambient concentrations of NO<sub>2</sub> from transportation emissions. Higher concentrations in NO<sub>2</sub> and O<sub>3</sub> occurred in succession in the daytime. The diurnal variation of O<sub>3</sub> concentration was analyzed. The daily cycle of NO<sub>2</sub> concentration reaches a maximum in the late morning and has smaller nighttime concentrations. The daily cycle of ozone concentration reaches the maximum in the afternoon and also becomes smaller for nighttime concentrations. In addition, relationships were found between O<sub>3</sub> and NO<sub>2</sub>. Monthly variations of ozone and NO<sub>2</sub> are presented. Some options to reduce ozone pollution are presented.展开更多
文摘Ground-level ozone is a harmful air pollutant associated with several health issues. Ozone concentrations have exceeded the National Ambient Air Quality Standards (NAAQS) in the Chicago metropolitan area on hot summer days for many years because of nitrogen oxide and volatile organic compound emissions. Annual fourth highest 8-hour ozone concentrations have been between 0.070 and 0.084 ppm at several monitoring sites in Cook county, during the 2016-2018 time period. The continuous measurement of nitrogen dioxide (NO<sub>2</sub>) and ozone (O<sub>3</sub>) was conducted in several communities in Chicago in 2017. The air pollution impacts the health of all who live in the area. The data were used to analyze correlations between the O<sub>3</sub> distribution and its association with ambient concentrations of NO<sub>2</sub> from transportation emissions. Higher concentrations in NO<sub>2</sub> and O<sub>3</sub> occurred in succession in the daytime. The diurnal variation of O<sub>3</sub> concentration was analyzed. The daily cycle of NO<sub>2</sub> concentration reaches a maximum in the late morning and has smaller nighttime concentrations. The daily cycle of ozone concentration reaches the maximum in the afternoon and also becomes smaller for nighttime concentrations. In addition, relationships were found between O<sub>3</sub> and NO<sub>2</sub>. Monthly variations of ozone and NO<sub>2</sub> are presented. Some options to reduce ozone pollution are presented.
