What is a common measure to mitigate air pollution in urban areas?

Expanding public transportation systems is a common and effective measure to mitigate air pollution in urban areas. By improving public transit options, cities can encourage more people to use buses, trains, and subways instead of relying solely on personal vehicles. This shift can lead to a significant reduction in the number of cars on the road, which in turn decreases emissions from gasoline and diesel vehicles that contribute to air pollution.

Public transportation systems can also be designed to be more environmentally friendly, incorporating electric or hybrid vehicles that produce fewer emissions. Enhanced public transit helps to reduce traffic congestion, which is often a contributing factor to air pollution, as idle vehicles emit more pollutants. Additionally, by making public transportation more accessible and efficient, cities can foster a culture that prioritizes sustainable travel options, further decreasing reliance on individual car ownership.

In contrast, measures like increasing road construction or encouraging personal vehicle ownership would typically exacerbate air pollution issues by facilitating more vehicles on the road. Reducing green spaces in cities can lead to higher temperatures and worsened air quality, as vegetation plays a critical role in filtering pollutants and providing clean air. Thus, expanding public transportation stands out as a proactive solution for improving air quality in urban environments.