Yet again, the Supreme Court has come down heavily on Punjab, Haryana and Uttar Pradesh to ‘stop’ the burning of paddy straw at this time of the year. Biomass burning is indeed the main cause of the noxious smog that envelops Delhi and adjoining regions in October and November – even as transport perhaps is the biggest polluter on an annual basis. It does not help that the air turns dense and still, as temperatures and wind speeds drop with the onset of autumn.

According to the data put out by the Ministry of Earth Sciences on a daily basis (called Decision Support System, or DCC, for Air Quality Management in Delhi), straw and stubble burning accounted for 26.4 per cent of PM 2.5 (particulate matter of 2.5 microns or less) in Delhi on November 8, and exceeded 35 per cent on November 3. The question is whether it can be stopped by fiat, without addressing its underlying reasons. Stubble burning is a compulsion. The paddy crop waste has to be cleared in about two weeks’ time to allow for the planting of wheat, which ideally should be completed by mid-November. There is no faster way to do so than burn it. What has changed over the last decade or so, since the Punjab Preservation of Subsoil Water Act 2009 came into being to arrest groundwater use, is that the paddy crop is sown and harvested late, leaving a very small window to clear the fields for wheat. The apex court has observed that this law needs a relook. If the crop waste is burnt a month earlier, its impact on air quality would be less, as the higher wind speeds would carry the smoke away from Delhi and its neighbourhood.

However, any review of the law to push paddy sowing back by about a month will worsen the groundwater crisis. The solution lies in reducing acreage under paddy — rather than merely tinkering with timelines, or focusing on ways to process the waste. The latter should be pushed, but incentives to transport the waste to the nearest machine may be required. Progressive farmers have suggested planting a summer maize crop, besides moong and sunflower. However, for maize (or any other crop) to become attractive (maize is grown barely over a lakh hectares, whereas paddy is grown over 3 million hectares), yields as well as procurement will have to improve. Paddy accounts for 87 per cent of kharif acreage in the State, despite Punjab’s rainfall levels being unsuited for paddy. Free electricity for agriculture since 1997 has ensured that paddy remains viable through groundwater irrigation. Efforts to break out of paddy should begin by questioning these subsidies and shifting incentives towards alternatives, while raising their yields.

Delhi’s poor air and Punjab’s water crisis are two sides of the same coin, or problem — too much paddy cultivation. But since transport is a major polluter in urban India, the autumnal smog over north India should be viewed as a national problem.