NEET BIOLOGY

Detailed explanation-1: -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-2: -Mexico faces a number of very serious environmental challenges. The provision of clean water to Mexico City, air pollution in the capital and other major cities, deforestation and erosion in rural Mexico are some of the most pressing problems.

Detailed explanation-3: -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-4: -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-5: -It earned the accolade of the world’s most polluted city. A management programme was introduced which introduced reforms that would clean up the air. Levels of ozone were reported to be around 500 parts per billion (ppb), they are now at a more respectable level of between 120 and 150 ppb.