The air pollution crisis in Delhi arises from a complex interaction of multiple sources. Together they contribute to the annual crisis, in which the Indian capital often ranks among the world’s most polluted cities.
For residents of Delhi-National Capital Region (NCR), the choice is clear: continue on the path of “death-by-breath” or strive for a future with the fundamental right to clean air.
Clean air is available in Delhi-NCR, but the path is fraught with many policy challenges. Although measures such as Graded Response Action Plan (GRAP) and National Clean Air Program (NCAP) have been introduced to reduce air pollution, these provide only short-term relief.
Implementing long-term solutions requires substantial financial investment. Political differences can hinder administrative coordination among states. Data gaps, especially in accurately identifying pollution sources, can limit the effectiveness of mitigation strategies. And encouraging large-scale behavioral change can be a difficult task.
The findings of a 2018 study on air quality by The Energy and Resources Institute (TERI) provide valuable insights into the sources of Delhi air pollution, which contribute to concentrations of respirable particulate matter (less than 2.5 micrometers in diameter or PM2.5). .
Vehicle emissions are responsible for about 24 percent of the city’s particulate matter levels. Industrial activities, especially from neighboring states, are responsible for 23 percent of PM2.5 pollution, fueled by outdated technologies and slow implementation of emission norms.
Residential biomass burned in rural areas around Delhi adds another 18 percent, especially in winter when the biomass is used for heating and cooking. Dust from construction activities and poorly maintained roads contributes 27 percent to particulate levels.
These sources are compounded by additional pollution from burning of seasonal crop residues in Punjab, Haryana and Uttar Pradesh, which increases in October and November.
Frequent temperature inversions in the winter trap bring pollutants closer to the surface, turning the city into a pollution hotspot. While pollutants such as nitrogen oxides and sulfur dioxide generally remain within acceptable limits, PM2.5 and PM10 levels consistently and severely exceed these limits. Therefore, targeted, long-term solutions are needed to address particulate matter pollution.
Delhi Air Pollution and Air Shed Management
A promising approach to tackling Delhi air pollution is the concept of air pollution management, which views air pollution as a regional challenge.
TERI’s study found that Delhi’s emissions contribute only 36 percent on average to the city’s respirable particulate matter concentrations in winter and 26 percent in summer, with the rest coming out of the city.
Activities in neighboring states – Haryana, Punjab, Uttar Pradesh and Rajasthan significantly affect Delhi’s air quality. For example, widespread burning of crop residues during the post-monsoon season in Punjab and Haryana is a major contributor to Delhi’s notorious winter smog.
The root cause of crop residue burning is the policy incentives to produce rice in this dry zone, which were originally created for food security purposes, but are no longer necessary.
Moreover, the policy orders of Punjab and Haryana banning paddy planting till the onset of monsoon, without a proper hydrological study on the actual impact of pre-monsoon planting on the groundwater table, leaves no time for farmers to harvest properly and utilize crop residues. This leaves them with no option but to burn crop waste.
However, farmers are an important political constituency, and these perverse policy incentives should be replaced by others that do not disadvantage farmers.
Effective airshed management requires cooperation to monitor and control emissions while recognizing that pollutants in these areas cross state boundaries.
Building a comprehensive emissions inventory for the entire airshed and conducting source apportionment studies can help identify pollution hotspots and guide targeted interventions.
Equally important is the transition to clean energy sources.
Delhi has reduced its dependence on coal by shutting down thermal power plants. However, the city and its surrounding areas must accelerate their transition to renewable energy sources such as solar and wind.
Expanding Delhi’s fleet of electric buses and providing incentives for electric vehicles can also reduce vehicle emissions. Charging infrastructure should be scaled up to support the growing adoption of EVs, while stricter emission standards should be implemented for petrol and diesel vehicles.
Another important area is urban planning and infrastructure development. Poorly managed construction activities generate significant amounts of dust, which contributes to Delhi air pollution. Adopting best practices such as covering construction sites, using water sprays on dust and enforcing strict waste management regulations can help reduce this problem.
Urban greenery also plays an important role in absorbing pollutants and regulating the local weather or “micro-climate”. Expanding green spaces and creating green belts around the city can provide a natural buffer against Delhi air pollution.
More technical intervention is also required. Advanced air-quality monitoring networks capable of providing real-time data are essential to track pollution levels and implement timely mitigation measures.
Artificial intelligence and machine learning can predict pollution episodes and identify high-risk areas, enabling authorities to take pre-emptive action. Smog towers and large-scale air purifiers, while not a panacea, can serve as complementary devices in areas with persistently high pollution levels.
Public participation is a cornerstone of any successful long-term strategy. Campaigns to encourage the use of public transport, carpooling, and the separation of wet and dry waste can significantly reduce air pollution.
Community-based initiatives, such as citizen science projects for air-quality monitoring, can foster a sense of responsibility and empower individuals to advocate for clean air.
Encouraging industries to adopt cleaner production processes and renewable energy can reduce their environmental footprint without compromising economic growth.
Furthermore, creating job opportunities in green sectors such as renewable energy, waste management and sustainable transportation can help balance economic development and environmental sustainability.
Addressing Delhi air pollution also requires policy reforms at the national and state levels.
Financial measures, such as subsidies for cleaner technologies and penalties for polluting practices, can move both businesses and individuals toward more sustainable options. In addition, better coordination between different government agencies is important to ensure that air quality management efforts are not fragmented.
Delhi can also take inspiration from cities around the world that have successfully tackled air pollution. Beijing implemented stricter vehicle emissions standards, transitioned to natural gas for heating, and invested heavily in public transportation. Los Angeles, once notorious for its smog, adopted stricter air quality regulations and promoted the use of electric vehicles.
Delhi’s air pollution is not an unmanageable problem.
Suresh Ramasubramanya Iyer Senior Fellow and Field Coordinator, Center for Air Quality Research, Institute of Energy and Resources, New Delhi.
Originally published under Creative Commons by 360 informationâ„¢.