Breathing in the dead of winter in northern India, and especially in Delhi, has become an almost risky experience. For millions of people, The cold is no longer just associated with scarves and coats, but also with face masks, stinging eyes, and burning throats., with the constant feeling of being in a kind of open-air gas chamber.
Over the past few decades, various official reports, international organizations and local media have painted an increasingly worrying picture. Air quality levels are soaring to levels that are tens of times higher than the safe limits set by the WHO.Hospitals are overwhelmed during the winter months, and air pollution is becoming one of the main health risk factors in India, on par with tobacco or poor diet.
A winter trapped under a dome of smog
As November approaches, A dense, whitish fog begins to settle over the Indo-Gangetic PlainIn one of the most densely populated areas on the planet, home to almost half of India's population, the air becomes heavy, barely moving, and visibility drops to the point of forcing flight cancellations, train delays, and disrupting road traffic.
The explanation lies in what specialists call the "winter trap". With the drop in temperatures and the absence of wind, a thermal inversion layer forms that blocks pollutants near the ground.The cold, dense air clings to the surface and acts as a lid, preventing dust, smoke, and rising gases from dispersing into higher layers of the atmosphere.
In Delhi, this situation is exacerbated by the geography itself. The city and its surroundings form a kind of bowl open to the south, partially surrounded by the barrier of the Himalayas.This orographic configuration makes it difficult for air masses to carry polluting particles to other places, so the smog mixture literally stays on top of the population for days or even entire weeks.
Winter wind speeds, which are often around three or four kilometers per hour, are insufficient to clear the atmosphere. What enters the air—industrial emissions, exhaust fumes, construction dust, smoke from fuels and agricultural burning—remains stagnant for long periods.generating a toxic cocktail that repeats itself year after year.
Sources of pollution: many pieces in the same puzzle
In Indian public debate, there has been a tendency to point to a single villain: the burning of stubble and agricultural waste in the neighboring states of Punjab, Haryana or Uttar PradeshIt is true that in October and November, when farmers remove the remains of the crops to make way for winter sowing, there is a peak of smoke visible even from satellite.
However, studies by the United Nations Environment Programme (UNEP) and other agencies make it clear that Winter pollution in India is the result of a combination of persistent sources., over which agricultural smoke temporarily overlaps. Among these hotspots, the following stand out:
- Emissions from private and commercial vehicles, which have grown unchecked in recent decades.
- Daily burning of biomass in rural and poor urban householdsmainly firewood and dung for cooking and heating.
- Pollution from industry and fossil fuel-based thermal power plants and the lack of Alternative energy.
- Dust from construction sites, brickyards, and unpaved floors, which rises and remains suspended with ease.
- Open burning of garbage in formal and informal landfills and in urban areas without adequate waste management.
To all this is added the aforementioned agricultural contribution. The burning of crop stubble temporarily increases the concentration of particles in the air during a few critical weeks.However, pollution levels remain extremely high in December and January, when this practice has almost completely ceased, highlighting the weight of permanent sources, especially road traffic.
The rise of the car and the abandonment of public transport
A large proportion of independent analyses agree that The explosive growth of the car fleet is one of the major drivers of pollution in Delhi and many other Indian cities.The country's capital now has more vehicles than Mumbai, Kolkata and Chennai combined, and the vast majority are privately owned cars and motorcycles.
This phenomenon is not limited to the large metropolis. The expansion of the upper middle class has boosted car purchases even in semi-urban areas that previously enjoyed relatively clean air.The result is permanent traffic jams, constant noise, and a cloud of toxic gases that adds to the other sources of pollution.
In parallel, India's economic and infrastructure model has strongly focused on road transport. While the network of motorways and roads has multiplied, the public railway has been left with an aging and saturated infrastructure.losing passenger and freight share to private trucks and buses.
State-owned road transport companies have also suffered decades of financial neglect, which has hampered the expansion of quality urban and regional bus networks. The number of cars, jeeps, and taxis is growing at a much higher rate than that of buses.This reinforces the vicious cycle: more traffic, more emissions, more pressure to widen roads, and even more motorized travel.
In this context, it is not surprising that More than half of Delhi's air pollution is attributed to transport emissionsespecially to diesel vehicles and older engines without sufficiently effective particle and nitrogen oxide control systems.
Energy poverty and biomass: when heating your home also pollutes
At the other end of the social scale, Millions of low-income rural and urban families still depend on firewood and other solid fuels for cooking and heating.Policies to replace these fuels with liquefied petroleum gas (LPG) or electricity have progressed, but they are still far from reaching the entire vulnerable population due to a lack of funding and infrastructure, and there is also a lack of investment in ecological homes. that improve insulation and reduce heating demand.
The consequence is that The burning of biomass—firewood, plant waste, manure—is estimated to be responsible for up to 30% of winter pollution in northern India.In villages, outdoor bonfires serve as makeshift stoves; in the outlying neighborhoods of cities, families resort to braziers or small fires to combat the nighttime cold.
The climate change It is disrupting agricultural calendars. The southwest monsoon arrives late and often lasts until OctoberThis shifts the rice planting and harvesting seasons, compressing the time between the kharif (summer) and rabi (winter) growing seasons. With less time to spare, farmers burn crop residue to quickly clear the fields, as allowing it to decompose naturally would significantly delay land preparation.
From a social point of view, this creates a cruel paradox. The poorest people are both those who involuntarily contribute the most to pollution out of necessity and those who suffer the most from its effects.because they cannot afford air purifiers, private medical care, or better-insulated housing.
The political battle over who is responsible for the smog
The central government and various state administrations have made efforts in recent winter campaigns to focus media attention on the burning of stubble. Heavy fines have been levied and applied to farmers in Punjab, Haryana, and Uttar Pradesh, arguing that their traditional practices are the main cause of unbreathable air in the capital.
However, several analysts and social movements warn that This narrative downplays the structural responsibility of the transport model and industrial development.Modifying the urban mobility system —by prioritizing rail, buses and non-motorized transport— would mean clashing with very powerful economic interests, such as the automotive and construction industries.
These critics argue that blaming the peasants is wrong. It also serves to pave the way for future reforms that favor the massive entry of large corporations into the agricultural sector.Portraying family farming as backward and polluting fits with a “modernization” agenda that, in practice, could erode the economic and political position of the peasantry.
Meanwhile, the farmers find themselves between a rock and a hard place. With increasingly tight profit margins and limited state supportThey argue that they have no realistic alternatives to the rapid burning of waste if they want to meet planting deadlines and stay afloat economically.
The sector's demands include greater public investment in machinery for managing crop residues, a real boost to crop diversification with guaranteed minimum prices, and technological support adapted to an increasingly variable climate. Without these measures, the discourse that “the peasants are to blame” is perceived as unfair and politically motivated..
Health impact: winter as a peak season for illnesses
The public health figures associated with winter pollution in India are devastating. In New Delhi's public hospitals alone, more than 200.000 cases of acute respiratory illnesses were recorded between 2022 and 2024., according to data from the Indian Ministry of Health presented to parliament.
During that same period, More than 30.000 patients with respiratory illnesses had to be hospitalized.Many of these patients present with severe cases of acute bronchitis, decompensated asthma, pneumonia, or chronic obstructive pulmonary disease (COPD). Doctors describe a situation in which emergency departments are overwhelmed every winter with recurrent respiratory crises, especially among children and the elderly.
The long-term epidemiological data are equally alarming. A study published in The Lancet Planetary Health, based on the Global Burden of Disease project, estimated that air pollution was linked to 3,8 million deaths in India between 2009 and 2019.Much of this burden is due to prolonged exposure to PM2.5 fine particles.
These particles, which are tiny in size, They are able to penetrate deep into the lungs and pass into the bloodstreamOnce inside the body, they promote inflammatory processes that are associated with cardiovascular diseases, strokes, neurological deterioration, and various types of cancer, especially lung cancer.
Experts warn that Air pollution has become one of the main risk factors for health in the countryplacing it on par with smoking or certain unhealthy dietary patterns. And, as with other environmental risks, it hits hardest those with the fewest resources to protect themselves.
Children, the elderly, and chronically ill patients: those most at risk
Organizations such as UNICEF have repeatedly emphasized that Children are especially vulnerable to air pollutionChildren's lungs are still developing, and constant exposure to high levels of PM2.5 and other pollutants can reduce their lung capacity for life.
Furthermore, Air pollution affects the immune system and neurological developmentTherefore, children subjected to this environmental stress for years have a greater risk of acute respiratory infections, learning problems, and possible long-term cognitive impairments.
In the case of older adults and people with pre-existing conditions—such as heart disease, hypertension, diabetes, or chronic respiratory illnesses—, Winter smog waves trigger a surge in the number of health crises and hospital admissionsMany families in Delhi acknowledge that at least one of their members has suffered pollution-related symptoms during the most critical weeks, ranging from eye and throat irritation to pharyngitis, recurring fever, or asthma attacks.
In lower-income neighborhoods, the problem is exacerbated because Access to quality healthcare is limited and expensiveGetting sick not only involves pain and life-threatening risks, but also loss of wages, debt to pay for consultations and diagnostic tests, and a spiral that pushes one into more poverty.
Experts also insist that pollution does not act in isolation. Its effect on health adds synergistically to other factors, such as working conditions, nutrition, socioeconomic level, genetics and previous medical history, creating a scenario of accumulated risk that is difficult to reverse without global emissions reduction policies.
Toxic air and solar energy: when smog also shuts down the panels
The impact of winter pollution in India goes beyond health and quality of life. The renewable energy sector, and in particular solar photovoltaic energy, is also being seriously affected due to the persistent presence of aerosols and toxic smog in the atmosphere.
Recent data from the company Solargis shows that In January 2024, northern India experienced its worst air quality in decades.with episodes of continuous smog lasting up to 20 days in some areas. This layer of suspended particles reduces the solar irradiance reaching the panels, causing significant drops in electricity generation.
Solargis' monthly Global Horizontal Irradiance (GHI) map for that month indicates drops of between 30% and 50% compared to long-term averages in regions such as Punjab, Haryana, and Uttar Pradesh. Together, these areas account for approximately 5 GW of installed solar capacityTherefore, the economic impact of such a drastic reduction in production is considerable.
In addition, the company has detected a trend towards several consecutive winters with solar performance below expectations, both in the north and in the center of the country, where the extension of the monsoon season and changes in weather patterns also play an important role.
Given this scenario, Indian solar operators and developers are Investing in high-resolution irradiance data and more detailed time series, which will allow them to better model the behavior of their plants in extreme smog and fog conditions, as well as design hybrid portfolios (solar, wind and battery storage) capable of mitigating climate variability.
Government measures and emergency plans
The magnitude of the problem has forced Indian authorities to implement a series of institutional measures. The Commission for Air Quality Management has been created, an agency with powers of coordination between states, and the National Clean Air Program has been launched, focused on reducing particulate pollution in major cities.
In Delhi, whenever the Air Quality Index (AQI) exceeds 400-500 points—levels categorized as “severe” and up to 35 times above WHO recommendations—, An emergency protocol is activated with restrictions on economic activity.Level 4, the strictest level of the national anti-pollution plan, includes measures such as:
- Restriction of certain industrial and construction activities.
- School closures and transition to online classesespecially on the most critical days.
- Teleworking recommendations to reduce commuting as far as possible.
- Restriction of access for non-essential diesel trucks to the capital.
Municipal authorities also resort to actions such as Paving sections of road that are still dirt, spraying the streets with water to reduce airborne dust or promote targeted campaigns for the use of face masks, especially among children, the elderly and those who spend more time outdoors.
In the longer term, Delhi has developed one of the world's largest subway networks, with more than 250 stations spread across nine linesIn addition to services like the Airport Express, which have proven to be very successful, without this mass transit infrastructure, the pollution situation would be even worse.
However, compliance with the rules and citizen involvement remain inconsistent. In a city with few sidewalks and a deeply rooted culture of motorized travel, even for very short journeys.The leap towards truly sustainable mobility is happening much more slowly than the environmental crisis demands.
The role of UNEP and the need for a change in behavior
From the United Nations Environment Programme, officials like Balakrishna Pisupati warn that Air pollution in India is very close to becoming a large-scale disasterIt is not just a seasonal annoyance, but a chronic problem whose effects accumulate in the body over time.
UNEP insists that, while policies and investments in cleaner technologies are essential, There will be no real success without a profound change in collective behavior.Governments, industries, households, travelers, tourists, community organizations, and the media need to be involved in a sustained way, not just for a few weeks in winter.
Among the proposals is strengthen policy coherence between different ministriesThis prevents subsidies for fossil fuel-intensive or highly polluting activities while simultaneously trying to reduce emissions in other sectors. The importance of cooperation between states is also emphasized, as air knows no administrative borders.
To channel this collaboration, UNEP has launched the Air Quality Action ForumIt's a platform that brings together large and small industries, healthcare professionals, young people, academics, civil society organizations, and media outlets. The goal is to share technological, operational, and behavioral solutions that can be replicated in different regions of the country.
In parallel, UNEP and the Indian Ministry of Environment are working on a national behavior change program focused on reducing individual environmental footprints, from car use to household waste management, including energy consumption and open burning practices.
All this is happening while India is making progress in its climate transition and consolidating itself as one of the countries that is investing most heavily in renewable energyHaving met some of its 2030 targets ahead of schedule, the reality on the ground shows that the fight against air pollution is lagging behind the pace set by health emergencies.
The toxic smog that hangs over Delhi and the Indo-Gangetic Plain every winter encapsulates a set of tensions that are difficult to resolve: a development model heavily dependent on cars and coal, enormous social inequalities, an agricultural sector pressured by climate and the market, and an institutional network that is still seeking to coordinate effectivelyEscaping this winter trap will require not only technology and regulations, but also bold political decisions and everyday changes in how we move, produce energy, and manage waste, so that the simple act of breathing ceases to be a risk in the heart of India, including innovative urban solutions such as the Smart Green Tower.
