Derk Bakker^1,, Hadia Pervaiz¹

Air pollution is a significant problem in Lahore, Pakistan. The reasons for this are a combination of geographic, climatic and anthropogenic factors. A smog episode in November 2024, which was blamed for a large part on rice crop residue burning (CRB) in Punjab provided an incentive to analyse the contribution of emissions from CRB to the overall air quality in the urban area of Lahore. The air pollution simulation model HYSPLIT was used with a focus on real emission PM_2.5 sources, and pollutant concentrations rather than trajectories. The meteorological and atmospheric conditions were obtained from two sources: GDAS and METAR of the international airport. The pollution sources were CRB fires obtained from satellite information and the mobile sources in Lahore. Satellite detected fires were found to be underestimated compared to actual observations using Google Earth. GDAS weather information did not reflect the local conditions well. Using both GDAS and METAR weather information showed that PM_2.5 from CRB contributed very little to the air pollution in Lahore, however only METAR information resulted in PM_2.5 emissions similar to those measured in the city. This study indicates that the focus of the government of Punjab should be on reducing emissions from urban rather than rural areas.

Air pollution, HYSPLIT, stubble burning, local weather, urban emissions, Lahore, Pakistan