It is not daily discomfort but reports on air quality that have led to some degree of awareness about how grim the health of our air really is. In 2018, a WHO report revealed that 14 of the 20 most polluted cities in the world are in fact Indian. No, the national capital didn’t top the charts. It was Kanpur, where nearly 2.9 million live and breathe. And Kanpur wasn’t the only city on the list from the country's most populous Uttar Pradesh. Varanasi, where an economy of faith operates; Lucknow, the political capital of Uttar Pradesh, and Agra, where the Taj Mahal stands, also found a place on the WHO list in which the national capital was on the sixth spot, a slight improvement from its number four spot in 2015.

In 2020, a Lancet study estimated the casualty burden due to air pollution at 1.6 million and the potential economic loss (due to premature death and morbidity) at USD 38 billion. For some perspective on resources and budgets, if there was a ministry dedicated to resolving air pollution, its allocation in the Union Budget would be second to only the Ministry of Defence that has been earmarked USD 72 billion. The question remains, if the resources kept aside for air pollution are so mammoth, why are we struggling to solve this problem.

The answer, I believe, is three-fold. First is the fact that air is a difficult medium to control. Unlike water, the air around us can’t be completely controlled through a system of pipes and filters. Second, air pollution is dependent entirely on climate/weather patterns. Even in 2023, our understanding and ability to forecast weather models accurately at hyper-local levels is questionable. Third are the trade-offs associated between cleaner air and profit/economic output, at least in the short-term. In developing countries like India, central and state governments periodically go to polls and are voted to power to enable growth in per-capita wealth, not to hinder or decrease it.

Therefore, ‘don’t do X’ mandates are very costly, politically and economically. The Covid lockdown was a striking example of this. How then do we manage air pollution through minimal prohibition? Through this piece, I argue that the answer lies in generating high-quality evidence. I use the word evidence and not data because I am attempting to map the problem in not just numbers. In order to tackle air pollution, we need answers to some key questions. These would be:

Firstly, how polluted is the air around me?

Standardisation is essential for generating evidence. Even as late as 2013, believe it or not, we in India were debating air pollution based on our own subjective opinion. The National Air Quality Index, launched in 2014, solved this problem to a certain extent. Across Delhi, 40 Continuous Ambient Air Quality Monitoring Stations (CAAQMS) now measure levels of seven pollutants (including PM 10 and PM 2.5). The data captured by these stations is fed into the National Air Quality Index (AQI), which is used for citizen advisory, and kicking in the Graded Response Action Plan. This enables concerned stakeholders to participate in the process of improving the quality of the air they’re breathing.

Notably, the 40 CAAQMS stations in Delhi cover only 33% of its area. To enable localised actions, Delhi is exploring the idea of establishing a network of low-cost sensors to inform policymakers and citizens. Such networks have been deployed successfully in cities like London and Beijing. Public access to such data also helps increase awareness and drive citizen-engagement initiatives.

Secondly, what are the activities that pollute my air? What is the contribution of each of these activities towards increasing air pollution?

It is said that a problem well stated is a problem half-solved. The above questions are answered by source apportionment studies, and form the basis of ‘stating’ the air pollution problem. For instance, past source apportionment studies for Delhi (conducted by TERI in 2016 and 2019) suggested that: (i) more than two-thirds of the sources causing pollution in Delhi are located outside the political boundary of Delhi, (ii) vehicular emissions are the largest contributor to PM 2.5 concentration in Delhi (43%), and (iii) road dust is the largest contributor to PM 10 concentration (36%) in the state. While these findings are important, they suffer from limited sampling periods and remain an averaging of seasonal variations. Standalone, these findings are not nuanced enough for efficient administrative action.

For instance, source apportionment studies revealed that on an average, vehicular pollution contributes to 15-25% of Delhi’s PM 2.5 levels. It would be helpful to administrators if they could know what was the PM contribution of 2/3/4 wheelers, the likely age of these vehicles, and the make/type. Similarly, instead of prohibiting all construction entirely during the Graded Response Action Plan, it would be helpful to understand if there is any specific construction material that accounts for most of the dust. In both examples, we can see three benefits of high-quality evidence.

Granular data will ensure that the number of people whose lives will be disrupted shall be minimal. This increases the political acceptability of the desired mitigation actions and can lead to better resource allocation for enforcement. Finally and most importantly, this will create opportunities for citizen engagement on air pollution.

Delhi has taken a crucial first step towards understanding its air pollution problem by launching a real-time source apportionment study. Since November 2022, cutting edge equipment is tracking pollutant concentrations and source apportionment at an hourly frequency and making this data available on a dashboard. Such data is critical to designing targeted air pollution related interventions.

Thirdly, how can data be used to curb air pollution?

Thus, from the view of the concerned authorities, the focus must be on ensuring that the designed interventions, such as mechanised sweeping of roads, water sprinkling on roads, or deployment of anti-smog guns, are being implemented at every level. For instance, if a senior government functionary wishes to view effective implementation of dust control measures, such as how mechanised roads sweeping/sprinkling machines are running or are they running for the stipulated duration? Or what is the average length of the road being swept/sprinkled? Such granular level of real-time data is easily accessible.

Moreover, for effective monitoring of the Winter Action Plan, a set of coordinated pollution control activities, the Delhi government uses a portal to track the activities of 20 government agencies (such as PWD, MCD). These include activities such as mechanised road sweeping/sprinkling, resolving open garbage burning etc. Thus, this portal ensures accountability of government agencies to the Winter Action Plan.

In my opinion, no number of data systems can substitute the citizens, the eventual stakeholders in the air pollution problem. To improve the quality of data, and avoid policy ‘blind-spots’, it is important to have a system for citizen grievance redressal. In Delhi, this is achieved through the Green Delhi App. The App provides citizens with an opportunity to report violations and solve the issues promptly. As of January 2023, the App has registered more than 60,000 complaints and has a resolution rate of more than 80%. The Green Delhi App is instrumental in identifying localised pollution hotspots that the existing network of air quality monitors cannot capture.

In a fast growing economy like India, air pollution is and will be a wicked problem. One of the likely ways in which it will be tackled effectively is by a clear and consistent focus on generating data upon which administrative action can be based. This will also mean tracing pollutions back to sources and mapping emissions real time. Embracing evidence and technology is the key to effectively managing air pollution. Knowing the problem fully well and in all its depth is key to addressing it.