“It looks like an apocalyptic scene. A post-war scenario. You see huge plumes of black smoke coming out. I don’t know how to describe it.” My friend Avinash was telling me about seeing fields of crop residue burn in Haryana and Punjab.

Of all my friends who realised before I did that development economics is environmental economics, Avinash Kishore has been teaching me the longest. Almost fifteen years ago, we met one another first upon arriving at graduate school. We both stood flummoxed by the oversized wooden doors at the entrance to the castle where Princeton houses graduate students. We said hello.

I doubt Avinash started telling me about the importance of electricity metering for groundwater conservation that very day. But it would have started soon. A few years later, Diane and I rode with him and his parents – a party of six with the driver of the classic white Ambassador – to his family’s farm land, outside of where they live in Muzzafarpur, Bihar.

A coal plant is ten kilometres away. The sharecropping farmer complains to Avinash’s family that he thinks the ash hurts the fields. Avinash himself grew up in a house right across a pond from the rail station, but it never occurred to him as a child to worry that it was bad for his health. “We were just worried about it as a nuisance: the coal dust would cover our beds.”

So, Avinash has been thinking about air pollution for a while. A few years before we visited his farm, Avinash worked with us to get r.i.c.e. started as an organisation. If there are any principles behind r.i.c.e.’s work, they include the importance of seeing what you are talking about in villages, and of making an opportunity to learn about something else while you are there. In the summer of 2017, Avinash was doing a survey in Punjab and Haryana about varieties of wheat and rice. He tacked on a last page of questions about crop burning.

By asking his questions in the summer, Avinash was not there for that year’s season of crop burning: “My lungs are dear to me!” But he did have going for him that farmers did not think that he was there to learn about why they burn their crops – because he was not. “The first 45 minutes were what wheat did you grow, why did you not change, why did you not get more yield, and then suddenly a page of questions about this.”

Avinash’s strategy matters because, technically, crop burning is illegal.

Bans on crop burning from central and state courts have had little effect on the practice of crop burning, but the bans might influence how much farmers were willing to tell a surveyor. Luckily, Avinash’s pages of inane seed details had established his team as harmless. Most farmers admitted to burning their crop residue even though it is illegal – a good sign that they were willing to tell him the truth.

So why do the farmers burn their crop residue, blazing their fields into an apocalyptic scene? Avinash analysed farmers’ answers to the crop burning questions with Tajuddin Khan, a coauthor who studies food policy. The farmers in Haryana and Punjab did not think that burning residue was a health risk, even for their own family. Avinash asked the farmers what mattered to their decision to burn their crops. Health did not register: “when it came to air pollution, most people had rated it as low, and I think it would have been even lower” if farmers were not trying to give a polite answer.

What mattered was the simple economics. Crop residue is almost useless. “Are you kidding me?” Avinash explained, “a stalk is what? It’s purely carbon. Carbon and a lot of moisture, and a little silica.” All that carbon, moisture, and silica is just in the way of getting the next crop planted. That is expensive. “Taking it out and dumping it has labour costs.”

But while the crop-burning apocalypse is new, the uselessness of the residue has been true for a long time.

Many farmers in Haryana and Punjab can afford irrigation, so they want to clear the monsoon crop to squeeze in a winter crop. This, too, is nothing new, Avinash emphasised: “the second crop has been around forever.”

What are changing fast are labour costs and capital costs: wages are going up in India, but machines are cheaper than ever before. Hiring workers to clear the fields is expensive. More and more farmers in Punjab and Haryana can afford combine harvesters. Unlike harvesting by hand, a combine leaves stalks in the field (unless it has an attachment in the back to flatten the stalks, which combines in India typically lack). ‘With manual labour, the harvesting happens closer to the root. If you go to a field that has been harvested with a combine harvester, the remaining stalk is closer to your knees.’ Basmati rice, Avinash points out, is a special case, because it must be harvested by hand to remain unbroken (and saleable at high prices). Consistent with his theory, basmati fields are not usually burned.

Why would a farm owner not simply offer lower wages, offering to pay farm workers only as much as they can afford? One possibility, according to Avinash, is that workers may not take the job. Labour markets are a special type of market where the laws of supply and demand do not always apply in the ordinary way. In part this is because the sort of job you have is a signal about what type of people you and your family are. For example, the caste-related complication of the labour market for latrine pit emptying is one reason why there is so much open defecation in rural India. Few people are willing to be hired to empty a latrine pit, a job that is unfortunately seen as ritually polluting, and is associated with the lowest social ranks. Avinash wonders if agricultural labour is coming to also be seen with stigma, as India’s economy grows: ‘if you stay as a farm labourer, there is no upward mobility,’ a worker might reason; ‘your son will not be able to become a government peon.’

But even if agricultural labour were not stigmatized, rising productivity and improving education are increasing wages. Meanwhile, more farmers can afford equipment like combine harvesters than ever before. Lighting stubble on fire remains free of (monetary) charge.

Reinvent the harvest?

The problem is economic, then. The solution, in an economics classroom, is obvious. Regulate it, tax it, do not let farmers impose this cost on everybody else. Presumably, the courts had this sort of reasoning in mind when they banned crop burning. But, whether their farms were tiny, modest, or large, many paddy farmers in Avinash’s survey admitted to burning their crop residue anyway. When you burn your crop residue, it is obvious to everyone and sometimes visible from space. Despite crop residue burning being both illegal and obvious, there is no penalty.

It would be possible to have an effective penalty, at least in principle. Avinash gave me an example: it is illegal to transplant paddy too early in the year, because then it needs more irrigation and consumes more of the water that everybody has to share. A government order in Punjab and Haryana requires paddy farmers to wait for transplantation until closer to the monsoon, rather than the peak of summer. If you violate the order, the penalty is severe: ‘They come with a tractor and plough your field back.’

It is understandable why farmers – some of whom are quite wealthy, but many of whom manage with small patches of land – would take the opportunities they have to make the money they can, without paying costs that they can avoid. Few of us go out of our way to pay costs that we do not have to. This is a classic market failure, familiar to any economics student. But when the government does not address it, it becomes a government failure, too. Unfortunately, the explanation for this enduring government failure is no social scientific puzzle: farmers are politically powerful.

The only solution is to meaningfully change farmers’ incentives: either by seriously penalising crop residue burning (which farmers will not like) or by implementing a subsidy or financial incentive that is only paid to growers that do not pollute the air. But such a subsidy would spend down the public purse, and will appear to some voters to reward bad behaviour. Faced with this dilemma, we might hope for a deus ex machina, in the mechanical form of a Happy Seeder, a device that mulches the straw residue from growing rice while planting new wheat seeds at the same time.

Tajuddin and Avinash presented a summary of their research, which concludes with a dry bullet point: “most farmers do not know much about happy-seeders”. They report that “less than 10 per cent of farmers in our sample had seen a happy seeder or knew anyone who used one”. Among over 1,000 Punjabi farmers who they interviewed, they found about 10 using a Happy Seeder.

The impulse to solve social or economic problems by inventing a new technology is a familiar one in development policy. Bill Gates’ foundation promises to end open defecation by reinventing the toilet. For every problem, there is now a smart phone app – and a grant to fund the app’s development. Technology can change people’s behaviour, but only if it meaningfully changes their options. After all, farmers adopted combine harvesters because they are cheaper.

Yet, as Ridhima Gupta and E Somanathan summariaed the sobering results from a careful study of the economics of Happy Seeders: “the gain in average profit is small and so while some farmers will see a small profit gain, others may see a small profit decline when they switch to using the new machine”. The evidence suggests that neither Happy Seeders nor any other technology will reinvent the harvest without a change in farmers’ incentives.

Air Why India Must Solve Pollution and Climate Change Together

Excerpted with permission from Air: Why India Must Solve Pollution and Climate Change Together, Dean Spears, Harper Collins.