If data for smog components were collected in the middle of summer instead of winter, which trend would you expect for ozone concentrations?

If data for smog components were collected in the middle of summer instead of winter, which trend would you expect for ozone concentrations?

• A. Ozone concentrations would be higher throughout the graph
• B. Ozone concentrations would be lower throughout the graph
• C. Ozone concentrations would stay the same
• D. Ozone concentrations would be unpredictable

Answer: (A)

Ground-level ozone is formed when sunlight drives photochemical reactions between nitrogen oxides (NOx) and volatile organic compounds (VOCs). In mid-summer, there is more solar radiation and higher temperatures, which speed up these reactions and increase ozone production. Because the conditions that generate ozone are stronger in summer, you would expect ozone concentrations to be higher across the graph compared with winter, when lighter, cooler conditions slow photochemical ozone formation. This seasonal pattern—more ozone with more sunlight—explains why summer data shows higher ozone levels.

Ground-level ozone is formed when sunlight drives photochemical reactions between nitrogen oxides (NOx) and volatile organic compounds (VOCs). In mid-summer, there is more solar radiation and higher temperatures, which speed up these reactions and increase ozone production. Because the conditions that generate ozone are stronger in summer, you would expect ozone concentrations to be higher across the graph compared with winter, when lighter, cooler conditions slow photochemical ozone formation. This seasonal pattern—more ozone with more sunlight—explains why summer data shows higher ozone levels.