GS-1: Urbanisation: problems and remedies

In News:Delhi’s pollution crisis: Why Bengaluru and Chennai have ‘good’ air quality

1.What are the primary factors contributing to Delhi’s severe air pollution, while cities like Bengaluru and Chennai maintain relatively good air quality?

Delhi, one of the largest megacities in India, faces a severe air pollution crisis that poses significant health risks and environmental challenges. In stark contrast, cities like Bengaluru and Chennai manage to maintain relatively good air quality.

1. Geographical and climatic factors:
   ● Topography and weather patterns: Delhi’s basin-like geography and surrounding hills trap pollutants. Winter inversions exacerbate pollution by preventing dispersion.
   ● Lack of wind: Low wind speeds in winter limit the movement of pollutants, causing smog accumulation.
2. Vehicular emissions: Delhi has one of the highest densities of vehicles in the world, leading to significant air pollution from exhaust fumes.
3. Industrial emissions: The presence of industries in and around Delhi contributes to air pollution releasing pollutants such as sulphur dioxide (So2) and particulate matter., particularly from power plants and manufacturing facilities
4. Construction dust: Large-scale construction activities in Delhi generate significant amounts of dust, which can worsen air quality.
5. Crop burning: The practice of farmers in neighbouring states like Punjab, Haryana, and Uttar Pradesh burning crop residue after harvest releases large amounts of pollutants into the air, which are then carried by winds to Delhi.
6. Population density: The high population density in Delhi leads to increased demand for transportation, energy, and other resources, further exacerbating air pollution.

In contrast, Bengaluru and Chennai have several factors contributing to their relatively good air quality:
● Geographical location: Bengaluru, for example, is located at a higher altitude (about 900 metres above sea level), which means better air dispersion.Chennai, being coastal, experiences regular winds from the sea, which help disperse pollutants more effectively than in Delhi.
● Industrial activity: Both cities have a lower concentration of heavy industries compared to Delhi.
● Green cover: Bengaluru’s abundant greenery helps absorb pollutants and improve air quality.
● Meteorological conditions: Prevailing wind patterns and frequent rainfall in Chennai help disperse pollutants.
● Urban planning: Both cities have relatively better urban planning and infrastructure compared to Delhi, which helps in managing traffic and pollution.

Addressing Delhi’s air pollution crisis requires a comprehensive approach that includes stricter emission controls, improved urban planning, better management of crop burning, and a shift toward cleaner energy sources.

PYQ

1. Mumbai, Delhi and Kolkata are the three mega cities of the country but the air pollution is much more serious problem in Delhi as compared to the other two. Why is this so?2015

Source:

https://www.newindianexpress.com/nation/2024/Nov/18/delhis-pollution-crisis-why-bengaluru-and-chennai-have-good-air-quality#:~:text=Why%20is%20this%20the%20case,disperse%20pollutants%2C%20improving%20air%20quality.