November 12, 2023

Annual Air Pollution Festival


SO here we are once again, regular like the seasons, with Delhi and the entire Indi-Gangetic plains right down to West Bengal shrouded in a grey haze of pollutants as visible in photographs from space.  13 of the world’s 20 worst polluted cities or towns in the world are in India, including Delhi, satellite towns and other urban centres in northern and eastern India. This has now become such a hardy and recurrent annual feature that it may as well be declared yet another festival of which we already have so many in this country. As with other Indian festivals, this one too has by now acquired ritual trappings. The press carries daily articles opining on different aspects, but really only providing snippets of information with little or no meaningful analysis leading to effective policies. The media discourse has utterly confused the issues, and obscured the basic causes behind high levels of air pollution and its major sources, thereby preventing a clear understanding of the problem and a focused policy direction for a long-term and permanent solution.

The same holds true for establishment political parties. The union government and the ruling dispensation, which daily clamour for control over the administration of Delhi, now only maintains a studious silence, leaving things to a committee and to the different states, while taking pot-shots at opposition-rules states. The Delhi government and its ruling party, which used to cry hoarse against the neighbouring states especially Punjab and Haryana formerly governed by the Congress and BJP respectively, now only speaks against pollutants coming from Haryana, obviously because Punjab is now ruled by AAP!

Even the august Supreme Court, which often shies away from important decisions which it says may cross the line separating it from executive or legislative jurisdictions, now questions the basis for different executive decisions, but then proceeds to itself pass orders directing this or that policy or executive action, which too have no basis in science or empirical evidence!

Marx said that history repeats itself, the first time as tragedy, and the next time as farce. But what does one say when a sorry history repeats itself annually?  


Let us first get to a basic understanding of the problem of air pollution in urban centres in India.

There is much talk of seasonal or other variations, weather conditions, wind flows, seasonal or other spurts in one or another pollution source, but not clearly identifying the major sources of pollution. Extensive discussions about farm fires in north-western states, the inversion phenomenon in winter wherein cold air stays close to the ground gets trapped, make it appear as if the problem is more acute in north India than in peninsular and southern India. In major coastal cities such as in Mumbai, Chennai and even to some extent Kolkata, sea-breezes regularly flush out air pollutants over these cities, ensuring lower ambient pollution and beguilingly low air quality indices. 

It needs to be clearly understood that total pollutants released into the air, especially over cities, come from specific sources in quantities that can be determined by scientific studies and models. Major sources of air pollution in any urban centre in India would mostly comprise vehicle exhaust, coal-fired power plants in the vicinity, brick and other kilns in the region, construction and ambient dust, domestic, industrial or commercial burning of solid fuels such as coal and firewood, open burning of garbage or waste, industrial air pollution including and especially from burning of highly polluting fuels such as rubber and poor grades of furnace oil etc in boilers or other equipment, diesel generators etc would be additional sources.

Of all these, as numerous studies have shown, vehicular pollution, construction and ambient dust, and industrial pollution are the major sources which account for most of the baseline or uniform, underlying air pollution in almost all Indian cities.

The main point here, however is that, besides these variations and seasonal factors, a finite and determinate quantity of pollutants are emitted from these sources in or near any given city. Out of this total quantity of pollutants, some will stay over these urban centres and their surrounding areas, and some will be blown away or otherwise diffuse through the air due to seasonal and daily variations including rainfall, winds, summer and winter etc.

The Air Quality Index (AQI) is a measure of pollutants determined by sensors placed at different points in the city, and often cited and used to categorise conditions as “good,” “poor” or “severe.” AQI is a good indicator of air pollution under current conditions including as influenced by seasonal and weather patterns, and can help guide additional seasonal or other variable responses. But we need to look closer at the main, or baseline, total air pollutants emitted in and around the city in order to determine, plan and implement long-term strategies to curb air pollution on a permanent basis.

So, if one looks at the numbers, Delhi, surrounding NCR and other Indo-Gangetic belt cities are being driven to panic by AIQ numbers of close to 500 due to seasonal spikes in farm fires and winter conditions. While farm fires etc can be tackled, the real worry should be the high baseline AQI of around 200-250 in almost all major Indian cities.


This is certainly not what is being done, or even being addressed, in any city in India or in the country as a whole. 

There is a National Clear Air Programme (NCAP) in existence which aims at a 20-30 per cent reduction of PM 2.5 and PM 10 (particulate matter of 2.5 or 10 microns or thousandths of a millimetre size), of which the former is particularly dangerous since it can easily penetrate into the lungs and cause serious respiratory diseases, compared to 2017 levels. The needle has barely moved on these indicators, and funds have mostly been spent only on providing sensors to different cities. No strategy as such is visible, and no effective inter-departmental coordination mechanism has been set up.

Instead, what country is witnessing is panic-driven knee-jerk reactions and false solutions offered by all and sundry without any scientific basis or evidence-based reasoning based, among other things, on valuable experiences of other countries which have successfully tackled air pollution in cities over decades resulting in steady and continuing low air pollution today. We shall learn about these in the next section.

In the current tragi-comedy in Delhi, there is first the over-concentration on farm fires in Punjab and Haryana which have been discussed ad nauseam including in these columns. Stubble burning is of course worrying, but the problem is not amenable to short-being caught between high costs and the urgent need to clear fields of straw to enable planting of winter wheat within an extremely short window of two-three weeks.  Various interventions of providing machines and subsidies to various user industries have indeed shown some results, but not enough.

The Centre's Commission for Air Quality Management (CAQM) has reported a substantial decrease in stubble-burning incidents in Punjab and Haryana between September 15 to October 29, of around 56 per cent and 40 per cent, respectively, compared to the same period last year. Yet as harvest time neared, this has risen again and spiked. Clearly, a more holistic, end-to-end solutions, which cannot be simply be left to market forces is required by state governments with pro-active support and coordination by the centre. It is pointless for the Supreme Court to peremptorily order the concerned state governments to ensure that all farm fires should be stopped forthwith, as it did earlier this week.

Besides this, the Delhi government has decided to introduce its vehicle-rationing “odd-even” scheme under which vehicles with number plates ending with odd or even numbers would ply only alternative days. The Supreme Court sneered at this idea, asked for evidence to prove that such a scheme works, and sharply called it “sheer optics”. But surely, in theory, a scheme which reduces vehicles on Delhi’s roads by half would cause a substantial dent in air pollution. This was clearly evidenced during the pandemic lockdown when, due to lack of vehicular movement, air quality in Indian cities was better than it had been in several decades!

International experience in Mexico, China and Brazil has shown that such schemes to reduce numbers of vehicles on the roads do indeed work, but have been thwarted to cunning vehicle-owner dissenting response of buying additional vehicles with different number plates to circumvent the “odd-even” norms. In Delhi, two-wheelers which account for 7 million vehicles, have been exempted!

At the same time, the SC asked the Delhi government to consider banning app-based taxis, with the latter then proposing to stop out-of-state taxis from entering Delhi. This would only curb a tiny fraction of the 1 million vehicles on Delhi’s roads! What evidence does the august Court have that this scheme would work?

The same applies to the infamous “smog towers” which the Supreme Court ordered to be installed in 2020 despite evidence-based reluctance of various agencies and academic institutions. Yet, in the past few days, the SC ordered the by now dysfunctional smog towers in Connaught Place to be restarted, even though studies have shown that the tower is effective only over a few tens of metres.

And now the Delhi government is preparing for cloud seeding to produce rain! More pipedreams!

Real solutions, which will require firm, goal-oriented implementation over a decade or so, lie in tackling the high baseline pollution, especially vehicular pollution, dust and different industrial and commercial pollutants. This calls for significant reduction of fossil-fuel (including CNG) based personal vehicles and replacement by preferably electric public transport, along with promotion of non-motorized transport such as bicycles and pedestrianization. Control of construction dust would require restructuring the construction industry towards controlled, off-site use of materials and pre-fabrication, along with sprinkling of roads and tree plantation along all roads. Other pollution sources too must be tackled through strict regulation and enforcement. There are no short cuts!


In sharp contrast to India, Europe as a whole has substantially improved its air quality over the past two decades by concerted and holistic efforts including strict enforcement of high standards for industrial, vehicular and domestic air pollution by cooking and heating fuels especially coal. These measures have been backed by EU and national legislation, national commitments with strict timelines, and a comprehensive approach tackling all sources of pollution and all major pollutants. 

As a result, more than half of EU countries, mostly in western Europe, have brought down average PM 2.5 levels to under the EU standard of 25 micro-grams per cubic metre, compared to the India average of well over 100, and aim to achieve the WHO standard of matter, especially PM 2.5. The EU has also sharply focused on the dangerous nitrogen dioxide emanating mainly from vehicles and thermal power plants, on surface level ozone, a major carcinogen, and on toxic carbon monoxide, which hardly find mention in the discourse in India. Having earlier tackled power generation and polluting industries, most present efforts are aimed at vehicular pollution.

Another outstanding example is Beijing, widely studied and appreciated by UN agencies and other international agencies. About a decade or two ago, Beijing had the dubious distinction of consistently ranked the most polluted city in the world, with PM 2.5 well in excess of 100. Its smog was notorious, driving many multinational companies and diplomatic missions to seriously consider and publicly speak about relocating out of Beijing. Even though China as a whole ranked quite poorly in international pollution rankings, it put in highly focused and major efforts into tackling air pollution in Beijing. It moved all coal-based power plants and industries out of the city, it ensured phasing out of older and more polluting vehicles, and introduced low-Emission Zones in the city where only the cleanest or electric vehicles were allowed, an idea also enforced in London and other European cities. Beijing has been transformed from a car-centred city to what agencies have described as an example of sustainable mobility, expanding urban rail, bicycle and pedestrian mobility. A major afforestation effort was also taken in the northern regions from where recurring dust-storms bringing fine dust into Beijing were curbed. Widespread use of domestic coal-burning stoves was also curbed. As a result of all these measures, Beijing’s air pollution levels have been reduced by almost half its earlier levels, also bringing down pollution in the huge extended tri-city “megapolis” area.

There is no reason at all why India could not emulate these international examples. But this would call for political will, planning and enforcement… and stop tilting at windmills!