NEET BIOLOGY

Detailed explanation-1: -Located in the crater of an extinct volcano, Mexico City is about 2, 240 metres above sea level. The lower atmospheric oxygen levels at this altitude cause incomplete fuel combustion in engines and higher emissions of carbon monoxide and other compounds. Intense sunlight turns these into higher than normal smog levels.

Detailed explanation-2: -Perched 7, 300 feet above sea level in a valley wrapped round by mountains and volcanoes, Mexico City has long suffered from thick layers of smog produced by cars, factories, and wildfires. Among the worst hazards of that air pollution for its 21 million inhabitants is PM 2.5, inhalable fine particulate matter.

Detailed explanation-3: -Population growth, increasing motorization and industrial activities, a constrained basin and intense solar radiation combined to cause intense air-quality problems of both primary and secondary pollutants.

Detailed explanation-4: -There are multiple sources of air pollution in Mexico City that have combined to result in its low air quality. Main sources are vehicle volume, manufacturing and industrial processes, garbage burning, mass populations, and land formation.