Ozone depletion

. Lahore's poisoned air is usually discussed as a winter smog problem. But now, Lahore has been identified by EU's Copernicus Atmosphere Monitoring Service among Asian cities experiencing "extremely poor" levels of ground-level ozone, an invisible pollutant whose formation is accelerated by heat and sunlight. In other words, the city's dirty air is increasingly colliding with a warming climate. Ground-level ozone is not emitted directly. It forms when nitrogen oxides and volatile organic compounds, released largely by vehicles, industry and other combustion sources, react in sunlight. Higher temperatures and stagnant conditions can accelerate these reactions and allow ozone to accumulate. The city has spent years lurching from one smog emergency to another, often responding when visibility collapses and particulate pollution reaches dangerous levels. Ozone poses a different challenge. It cannot necessarily be seen or smelled, yet excessive exposure can cause breathing difficulties, aggravate asthma and reduce lung function. The WHO recommends that the maximum daily eight-hour mean should not exceed 100 micrograms per cubic metre. Pakistan should regard the warning as part of a broader climate threat rather than another entry in Lahore's long pollution record. Extreme heat is already a serious health risk across the country. Lahore needs reliable monitoring of ozone alongside particulate matter, and stricter vehicle and industrial emission standards. There is also no escaping the regional dimension. Ozone and its precursor pollutants can travel great distances, while CAMS data show elevated concentrations extending far beyond individual cities. Pakistan and its neighbours therefore have an interest in treating the Indo-Gangetic airshed as a shared environmental system. Cross-border cooperation on emissions data and pollution control should be pursued even when political relations are difficult. Air currents recognise no frontier.