In recent weeks, parts of Pakistan and India experienced extremely high levels of air pollution. Some measures of air quality suggest particulate matter in these areas was 10 to 15 times greater than acceptable levels. In Lahore, Pakistan, and New Delhi, India, local authorities canceled school, banned some types of vehicles, and restricted construction projects in an effort to reduce pollution and manage the consequences for human health.
To understand the causes and consequences of this pollution, Good Authority editor Christopher Clary spoke with Saad Gulzar, an assistant professor of politics and international affairs at Princeton University. Gulzar is coauthor (with Gemma Dipoppa) of a new study in the journal Nature on the topic.
Christopher Clary: Why has air pollution been so bad recently in parts of India and Pakistan, and why does this seem to be a recurrent problem for the region in these winter months?
Saad Gulzar: While there are many contributors to poor air quality throughout the year in India and Pakistan – including vehicles, industry, and brick kilns – the situation is worsened in the winter months by stubble burning by millions of farmers after the rice harvest around the months of October and November. Stubble burning is the practice of setting fire to crop residue, like rice and wheat stalks, after harvest to clear fields quickly for the next planting. It accounts for about 40 to 60% of peak pollution during these winter harvest months. Despite being illegal, stubble burning is prevalent due to its cost-efficiency for farmers – using fire to clear fields is far cheaper than alternative methods like using costly harvesters.
In addition to the spike of polluting activity, atmospheric factors like thermal inversion further exacerbate the problem. Thermal inversion is a process where a layer of cooler air close to the ground is trapped under a layer of warmer air, preventing pollutants like smoke and dust from rising and dispersing. This is one reason why you see a cloud of smoke over the northern Indian subcontinent during the winter months in satellite images.
What are the consequences of air pollution at such high levels?
The consequences are devastating, with air pollution responsible for 2 million deaths annually in South Asia. We show that high levels of particulate matter (PM2.5) from burning crop residue directly impact public health, particularly among children. For instance, taking in-utero exposure to air pollution from crop burning from average levels to twice the average increases child mortality by an additional about 25 deaths per 1,000 births. More generally, previous work has shown that air pollution impairs child development, reduces worker productivity, and severely burdens health systems.
Your research finds the governments are not powerless over these developments. How did you study how governments regulate the problem, and what did you find?
We conducted a decade-long analysis using satellite data, wind patterns, and administrative boundaries to study the political economy of crop burning. Our research revealed that bureaucratic incentives significantly influence pollution control. Crop burning, as detected via satellites from space, increases when pollution is likely to affect neighboring jurisdictions, but decreases when pollution impacts the bureaucrats’ own districts. Furthermore, punitive actions by bureaucrats – like fines or penalties – deter future violations. These findings challenge the notion that the problem is intractable, showing that existing government structures, when appropriately incentivized, can bring significant control to mitigate pollution.
I guess I’m curious: You show that governments can do more to deter pollution, but are you optimistic that they will do so?
There is potential for optimism because our findings demonstrate that bureaucratic actions can yield measurable and substantively large reductions in pollution. However, the path forward requires sustained political and public pressure to prioritize air quality. Governments must strengthen bureaucratic incentives and implement scalable, cost-effective alternatives for farmers. While progress may be slow given competing governance challenges, the evidence underscores that even modest improvements in bureaucratic focus and enforcement can have substantial public health benefits.
