Why are inversions dangerous?

• A. They contribute to cleaner air by diluting pollutants.
• B. They reduce pollutant concentration through mixing.
• C. They rarely affect human health.
• D. They trap pollution close to people, making air quality worse.

Answer: (D)

Temperature inversions create a lid over the lower atmosphere. When the air near the ground is cooler than the air above it, vertical mixing stalls and a stable layer forms. Pollutants emitted at ground level—like vehicle exhaust and industrial emissions—aren’t diluted as they normally would be, because the air can’t rise and disperse them. That causes pollutants to accumulate near people, raising concentrations and making air quality worse. In such conditions, small changes in wind or additional emissions can lead to sharp spikes in exposure, which can worsen respiratory and cardiovascular health. So inversions are dangerous because they trap pollution close to the ground rather than spreading it out.