Lahore woke on Monday, 9 November, to air rated hazardous, with monitoring stations across the city recording some of the worst readings of the season so far. According to data from IQAir cited by Bloom Pakistan, the citywide air quality index (AQI) stood at 563 at 8am, while individual stations reported far higher figures.

The highest reading came from the CERP Office, where the AQI reached 898. Burki Road Paragon B recorded 862 and ARM recorded 754. Other areas were little better: Allama Iqbal Town stood at 712, Samanabad at 719, Gulberg III at 683, Forman Christian College at 669 and Tufail Road at 657. Fine particulate matter, PM2.5, was identified as the main pollutant, with its concentration reaching 357 micrograms per cubic metre.

A week of very unhealthy air

The morning's readings followed a grim week for the city. A report by the Pakistan Air Quality Initiative, reported on 9 November, found that Lahore's average AQI was 268 between 1 and 7 November, peaking at 335 on 2 November. Five of the seven days fell in the very unhealthy category and two in the hazardous category.

Average PM2.5 over the week was 215.5 micrograms per cubic metre, about 14 times the World Health Organization guideline of 15. The report said PM2.5 this year was 25 per cent higher than in the same period last year, and that it was the third worst week for air pollution in Lahore in a nine-year record. Residents breathed air rated very unhealthy or hazardous on every day of the week.

What is driving the smog

The report pointed to low night temperatures and low wind speed, which kept pollutants trapped close to the ground. Fire incidents also played a part: the city recorded an average of 54.8 fire incidents a day during the week, and on days with at least 11 fire incidents the average AQI was 207, compared with 158 on other days. On 2 November, NASA satellites identified 488 fire incidents within 300 kilometres of Lahore, 204 of them within 100 kilometres.

The report names November and December as the worst months of the year for air quality in the city, suggesting the conditions affecting daily life are likely to persist. The latest readings are a sharp deterioration from the previous day, when Lahore recorded an AQI of 292 while Nankana Sahib hit 685.

Health experts advise residents, particularly children, older people and those with respiratory conditions, to limit outdoor exposure, wear a mask when outside and keep windows closed during the worst hours of the day.