Model Answer
0 min readIntroduction
Air pollution is a critical environmental challenge in India, particularly in its urban centers. While Mumbai, Delhi, and Kolkata are all mega-cities facing this issue, Delhi consistently experiences significantly higher levels of air pollution. This disparity isn’t accidental; it stems from a complex interplay of geographical, meteorological, and human-induced factors. The Air Quality Index (AQI) frequently registers ‘severe’ or ‘hazardous’ levels in Delhi, especially during winter, a situation less common in Mumbai and Kolkata. Understanding these contributing factors is crucial for devising effective mitigation strategies.
Geographical Factors
Delhi’s landlocked location plays a significant role. Unlike Mumbai, which benefits from sea breezes that disperse pollutants, and Kolkata, which has some access to Bay of Bengal winds, Delhi is surrounded by land. This restricts the natural flushing out of pollutants. The Indo-Gangetic Plain, where Delhi is situated, acts as a basin, trapping pollutants.
Meteorological Factors
Several meteorological conditions exacerbate Delhi’s air pollution:
- Temperature Inversions: During winter, temperature inversions are common. A layer of warm air traps cooler air below, preventing vertical mixing and concentrating pollutants near the ground.
- Wind Patterns: Delhi experiences relatively calm wind conditions during winter, reducing the dispersion of pollutants.
- Rainfall: Lower rainfall in Delhi compared to Mumbai and Kolkata means less natural washing away of pollutants.
Anthropogenic Factors
Stubble Burning
A major contributor to Delhi’s winter pollution is stubble burning in the neighboring states of Haryana and Punjab. After the harvest season, farmers often burn crop residue to clear fields quickly and cheaply. The smoke travels to Delhi, significantly increasing PM2.5 and PM10 levels. This is less prevalent around Mumbai and Kolkata due to different cropping patterns and agricultural practices.
Vehicle Emissions
Delhi has a high vehicle density, including a large number of older, more polluting vehicles. While Mumbai and Kolkata also have significant traffic, Delhi’s vehicle population and the proportion of older vehicles contribute substantially to its air pollution. The implementation of Bharat Stage VI emission norms has been slower in some areas surrounding Delhi.
Industrial Activity
Although industrial activity is present in all three cities, the concentration of small-scale industries and the prevalence of polluting fuels used in these industries are higher in and around Delhi. Unregulated industries contribute significantly to particulate matter and other harmful emissions.
Construction Dust
Rapid urbanization and construction activities in Delhi generate substantial dust pollution. Poor enforcement of dust control measures at construction sites further exacerbates the problem. Mumbai and Kolkata, while also undergoing construction, have comparatively stricter regulations and enforcement mechanisms.
Comparative Analysis
| Factor | Delhi | Mumbai | Kolkata |
|---|---|---|---|
| Location | Landlocked | Coastal | Coastal |
| Wind Patterns | Calm during winter | Sea breezes | Bay of Bengal winds |
| Stubble Burning | High impact from neighboring states | Minimal | Minimal |
| Vehicle Density | Very High | High | High |
| Industrial Pollution | Significant, many small-scale industries | Moderate | Moderate |
Conclusion
Delhi’s severe air pollution problem is a result of a unique combination of unfavorable geographical conditions, meteorological patterns, and significant anthropogenic pressures. While Mumbai and Kolkata face air quality challenges, they benefit from coastal influences and comparatively lower contributions from factors like stubble burning. Addressing Delhi’s pollution requires a multi-pronged strategy involving stricter vehicle emission standards, control of industrial pollution, regulation of construction activities, and a sustainable solution to stubble burning, alongside regional cooperation with neighboring states.
Answer Length
This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.