The Air Quality Index (AQI) remained unhealthy in Lahore as the smog threat continued to loom in the capital of Punjab province. The AQI is calculated based on five categories of pollution: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide. The Air quality index (AQI) rate was recorded between 178 to 200 in the early morning. It means, the air in Lahore is very unhealthy. AQI as high as 151-200 is considered unhealthy, while an AQI rating between 201 to 300 is more harmful and AQI over 300 is dubbed extremely hazardous.

The lowest temperature in Lahore was recorded at 23 degree centigrade in Lahore. According to experts, an increase witnessed in air pollution in winter, change in the wind speed, wind direction and sliding minimum temperature increases air pollution. The air becomes heavier in the winter as compared to summer, causing poisonous particles in the atmosphere to move downwards and making the atmosphere polluted. As a result, a layer of polluted particles, including large amounts of carbon and smoke, covers a city. The smoke produced by burning crop remnants, factories and burning coal, garbage, oil or tyres enters the atmosphere and the effects of this appear at the onset of winter and remain till the season’s end, experts said.

Credit: Independent News Pakistan (INP)