Delhi Pollution: A Clearer Outlook?

Delhi, India's capital territory, is considered the world's most polluted megacity. The air pollution in Delhi is so severe that it is estimated to reduce the lifespan of its residents by an average of 7 to 12 years. The poor air quality in Delhi is caused by a combination of factors, including vehicle emissions, industrial activities, construction dust, agricultural fires, and the burning of waste. While efforts have been made to improve the air quality, the problem persists, and it has become an annual health crisis for the city's residents.

Delhi's air quality is the worst of any major city in the world

Delhi, the capital territory of India, has the worst air quality of any major city in the world. According to a World Health Organization (WHO) survey of 1,650 world cities and a US-based Health Effects Institute survey of 7,000 cities, Delhi's air quality is the poorest. The city's poor air quality affects the districts around it, and air pollution in India is estimated to kill about 2 million people annually. India has the highest death rate from chronic respiratory diseases and asthma, according to the WHO.

In Delhi, the lungs of 2.2 million children, or 50% of all children, are irreversibly damaged due to poor air quality. Research also shows that pollution can lower children's immune systems and increase the risks of cancer, epilepsy, diabetes, and even adult-onset diseases like multiple sclerosis. Children are more vulnerable to the negative effects of air pollution as they are still growing and developing, which means they breathe a higher volume of air per kilogram of their body weight. They also tend to spend more time outdoors and are thus more exposed to harmful pollutants.

The air pollution in Delhi is caused by a combination of factors, including vehicle emissions, dust, industrial activities, and agricultural fires. In November 2024, Delhi recorded its worst air quality of the season, with a 24-hour Air Quality Index (AQI) reading of 491, classified as "severe plus." This level indicates hazardous conditions with significant health impacts, particularly for vulnerable populations. The reading marked the highest AQI level for Delhi in 2024 and was more than 30 times the World Health Organization's (WHO) limit.

To address the air pollution crisis, the Delhi government has implemented several measures, such as shutting down schools and offices, banning construction work, and restricting the movement of non-essential trucks and buses. However, these measures have had limited success, and Delhi continues to struggle with poor air quality, which has become an annual challenge.

The city's air pollution is caused by vehicle emissions, dust, and industries

Delhi, the capital territory of India, has the worst air quality of any major city in the world. The city's air pollution is caused by a combination of vehicle emissions, dust, and industrial activity.

Vehicle emissions are a significant contributor to Delhi's poor air quality. The city has an estimated 11.2 million registered motor vehicles, including cars, buses, and two-wheelers, with an increase of around 27% since 2015. These vehicles emit harmful pollutants such as particulate matter (PM2.5 and PM10), nitrogen oxides (NOx), and carbon monoxide (CO). In fact, vehicles constitute about 78% of NOx emissions and are the largest contributors to PM2.5 and PM10 emissions. The poor air quality has severe health impacts on residents, reducing life expectancy by an average of 7-12 years.

Dust is another major factor in Delhi's air pollution. Construction activities, unpaved roads, and road dust contribute significantly to the problem. It is estimated that dust accounts for about 38% of PM2.5 pollution in the city and 56% of PM10 pollution. The geographical location of Delhi also plays a role, as winds can bring dust and haze from other regions, trapping pollutants and creating smog.

Industrial emissions are also a key contributor to Delhi's air pollution. Industries account for around 41% of PM10 and 44% of PM2.5 pollution in the National Capital Region (NCR). The burning of fossil fuels, industrial discharges, and production plants release harmful pollutants into the atmosphere, with several hundred to over a thousand tons of pollutants released from factories alone each year.

The combination of these factors has severe consequences for the residents of Delhi, leading to respiratory and circulatory issues, cancer, and other health problems.

Stubble burning by farmers contributes significantly to Delhi's air pollution

Delhi, India's capital, is considered the world's most polluted megacity, with a mix of factory and vehicle emissions, as well as seasonal agricultural fires contributing to the poor air quality. The air pollution in Delhi has become so severe that, on average, each resident loses 12 years of their life expectancy.

While there are many factors contributing to Delhi's air pollution, stubble burning by farmers in neighbouring states is a significant issue. Stubble burning refers to the intentional incineration of crop residue by farmers after the harvest. This practice is common in the agricultural states of Punjab, Haryana, and Western Uttar Pradesh, which surround Delhi. According to the Indian Agricultural Research Institute (IARI), around 14 million tons of rice stubble are burned every year in India, with Haryana and Punjab alone contributing 48% to this amount.

The major reasons behind stubble burning include the short time between rice harvesting and wheat sowing, as well as a lack of knowledge among farmers about alternative methods to deal with crop waste. As a result, the burning of stubble releases toxic pollutants into the atmosphere, including harmful gases such as carbon monoxide, methane, and volatile organic compounds. These pollutants form a thick layer of smog, leading to detrimental effects on both air quality and human health.

The impact of stubble burning on Delhi's air quality varies depending on the day and weather conditions. For example, according to data from the Indian Institute of Tropical Meteorology (IITM), stubble burning accounted for just 1.3% of Delhi's air pollution on October 19, 2024. However, it is predicted to contribute 2.3% and 2.4% on October 20 and 21, respectively, indicating an upward trend. In contrast, vehicular emissions within Delhi are a more significant contributor, accounting for around 14.2% of the city's air pollution.

Despite the varying contributions, stubble burning remains a critical issue that needs to be addressed. The central and state governments have implemented various schemes and incentives to encourage farmers to adopt alternative methods for crop residue management. However, the problem of stubble burning and subsequent air pollution in Delhi and the surrounding areas persists, highlighting the need for stronger policy interventions and centre-state partnerships to combat this complex issue.

The Indian government has implemented various initiatives to address the issue

In addition to the NCAP, the Indian government has also introduced the Bharat Stage Emission Standards (BSES). These standards, modelled after European regulations, regulate the output of air pollutants from ignition engines, including motor vehicles. The implementation of stricter phases over time has restricted the sale and registration of non-compliant engines or cars.

The government has also taken steps to incentivise the use of electric vehicles (EVs). Residents of Delhi receive cash back when purchasing two- or three-wheeled EVs, which are the primary modes of transportation in the city. As a result, about 12% of new vehicles sold in Delhi are now electric. The government is also transitioning the public bus fleet to EVs, having previously converted them to natural gas.

To monitor air pollution levels and identify the types of emissions contributing to them, more than 40 real-time monitoring stations have been installed in the city. This data helps inform policy decisions and track the effectiveness of implemented measures.

While the impact of these initiatives may take time to be fully realised, the Indian government's efforts demonstrate a recognition of the severity of Delhi's air pollution problem and a commitment to improving air quality for the health and well-being of its citizens.

Despite efforts, Delhi's air pollution remains a persistent problem

Despite efforts to tackle the issue, Delhi's air pollution remains a persistent problem. The city has been dubbed the world's most polluted megacity, with its poor air quality causing irreversible lung damage in 50% of its children. The situation has become so dire that, in November 2024, Delhi recorded its worst air quality of the season, with hazardous conditions that significantly impact the health of its residents.

The Indian government and the local Delhi government have implemented various measures to combat the pollution, but the efforts have not been sufficient. The national government has introduced initiatives such as the Bharat Stage Emission Standards, which regulate air pollutants from ignition engines, and the National Clean Air Programme, targeting 100 cities with the aim of enhancing air quality by 2026. In addition, the local Delhi government has shut down coal-fired power plants, incentivized electric vehicle purchases, and installed real-time air pollution monitoring stations.

However, the root causes of the pollution have not been adequately addressed. Experts argue that the transportation sector, with its millions of cars, scooters, and auto-rickshaws, is a major contributor to the problem. The city's growing construction industry, which lacks pollution controls, and the burning of agricultural waste by farmers in neighboring states also play a significant role.

The annual smog season in Delhi, which usually occurs during the winter months, exacerbates the problem. The cold temperatures trap toxic pollutants from vehicles, rubbish fires, construction, and factory emissions, creating a thick cloud of smog that hangs over the city. The situation has become so severe that, in recent years, schools and offices have been forced to close, and people have been advised to stay indoors.

The health impacts of Delhi's air pollution are dire, with residents experiencing respiratory issues, asthma, and reduced life expectancy. The poor bear the brunt of the pollution, with many labourers working outdoors for long hours and returning to homes that offer little protection from pollutants. The economic impact is also significant, with businesses losing customers and tourists avoiding the city due to the hazardous air quality.

While the Indian government and the local Delhi authorities have taken some steps to address the issue, a more comprehensive and coordinated approach is needed to tackle the root causes of the pollution and bring about a significant improvement in Delhi's air quality.

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