"Bad" ozone, harmful to human health and the environment, is found in the troposphere. This is the lowest layer of Earth's atmosphere, extending from the ground up to about 7-10 miles (11-16 kilometers). Unlike "good" ozone in the stratosphere, which protects us from harmful UV radiation, tropospheric ozone is a pollutant formed when sunlight reacts with various chemicals released by human activities and natural processes.
Understanding "Good" vs. "Bad" Ozone
It's crucial to distinguish between the two types of ozone:
- "Good" Ozone (Stratospheric Ozone): Located in the stratosphere, this ozone layer absorbs harmful ultraviolet (UV) radiation from the sun, protecting life on Earth.
- "Bad" Ozone (Tropospheric Ozone): Found in the troposphere, this ozone is a harmful air pollutant that contributes to respiratory problems and other health issues. It's a secondary pollutant, meaning it's not directly emitted but formed through chemical reactions involving other pollutants.
Sources of Tropospheric Ozone
Tropospheric ozone forms when sunlight interacts with:
- Nitrogen oxides (NOx) emitted from vehicles, power plants, and industrial sources.
- Volatile organic compounds (VOCs) released from solvents, paints, and other industrial processes, as well as from natural sources like trees.
Health Effects of Tropospheric Ozone
Exposure to high levels of tropospheric ozone can cause:
- Respiratory irritation and inflammation.
- Reduced lung function.
- Aggravation of asthma and other respiratory conditions.
- Increased susceptibility to respiratory infections.
The U.S. Environmental Protection Agency (EPA) and other organizations monitor ozone levels and provide information on air quality to protect public health. Understanding the difference between "good" and "bad" ozone is key to appreciating the importance of clean air initiatives and pollution control measures.
