제 26 호 Ozone: The Invisible Smog Choking Our Cities
Kicker: SCIENCE
Ozone:
The Invisible Smog Choking Our Cities
By Sol-Mi Lim, Cub-reporter
As temperatures rise and air stagnation intensifies during the summer months, ozone (O₃) pollution is becoming a growing concern across urban areas. Unlike the protective ozone layer in the upper atmosphere, ground-level ozone is a harmful pollutant formed when nitrogen oxides (NOx) and volatile organic compounds (VOCs) react with sunlight. High concentrations typically occur between May and August, especially during the afternoon hours.
In response, the Ministry of Environment has launched a “Summer Ozone Management Plan” to minimize health risks by reducing the emissions of ozone precursors and enhancing public awareness. With ozone advisories issued more frequently, particularly in densely populated and industrial regions, the government is prioritizing targeted monitoring, emission control, and customized action plans to safeguard vulnerable populations. As climate change continues to drive higher temperatures and stronger sunlight, comprehensive efforts to manage ozone pollution are more urgent than ever.
NASA ozone watch
Causes of Ozone Formation
Ozone at ground level forms through complex chemical reactions. The main contributors are volatile organic compounds (VOCs) and nitrogen oxides (NOx), which are released into the atmosphere by vehicle exhaust and industrial activities such as at factories and power plants. When these substances are exposed to intense sunlight, a photochemical reaction occurs. This process creates ozone at the surface, especially in summer when strong sunlight is common. Unlike the ozone in the stratosphere, which protects life from ultraviolet radiation, high concentrations of ground-level ozone act as a dangerous pollutant. Studies show that cities often experience ozone level spikes, sometimes exceeding 0.12ppm on clear summer afternoons—a value well above safe standards.
Health Impacts of High Ozone Concentration
Ozone pollution is a pressing public health concern. High concentrations can irritate the respiratory system, causing coughing, throat discomfort, and chest pain. Prolonged exposure is known to decrease lung function and worsen conditions such as asthma and other respiratory diseases. Recent research indicates that ozone exposure may trigger asthma attacks by about 20% during the hottest months.
Children, older adults, and people with existing respiratory problems are especially vulnerable. Scientific evidence also points to the harmful effects of ozone on the cardiovascular system—regular exposure is associated with an increased risk of heart disease and stroke. One study found that long-term ozone exposure could raise overall mortality risk by over 10% in susceptible groups. Once an ozone advisory is announced, following proper guidelines is necessary. Citizens should reduce outdoor activities, especially strenuous exercise, and stay indoors with windows closed to limit exposure. If going outside is unavoidable, wearing a mask and avoiding peak ozone hours—from 2p.m. to 6p.m.—are recommended for additional protection.
Practical Solutions: Everyday Efforts to Lower Ozone Pollution
Individual choices can make a measurable difference. Cutting down on car use and choosing public transport or bicycles helps reduce VOC and NOx emissions. Adopting energy-saving habits—like turning off unused lights and unplugging electronic devices—can decrease emissions from power plants. It is also advisable to avoid excessive use of air conditioners and printers during periods of high ozone. On campus, students are encouraged to take the initiative in eco-friendly campaigns, promote more bicycle use, and participate in campus-wide energy-saving programs. These collective efforts contribute to a cleaner environment and demonstrate that personal actions matter in the fight against ozone pollution.
Beyond personal protection, everyone has a role to play in lowering ozone pollution. Reducing vehicle use by opting for public transportation or cycling, as well as adopting energy-saving habits such as turning off unnecessary lights and electrical devices, directly decreases the emission of ozone precursors. Avoiding excessive use of air conditioners, printers, and other electronic equipment, especially during high ozone periods, further supports these efforts.
University students, in particular, can take the initiative in eco-friendly campaigns that promote cycling, support campus-wide programs to reduce electricity consumption, and encourage classmates to participate in collective environmental action. Comprehensive and responsible participation in these activities not only protects vulnerable populations but also demonstrates how individual actions contribute to broader environmental change.The challenges posed by ozone pollution require both vigilance and proactive stewardship. By following official guidelines and making conscious choices in daily life, citizens can help limit ozone formation, safeguard community health, and build a more sustainable urban future.
