LAHORE – Air pollution originating across the border during Diwali celebrations significantly contributed to the deterioration of air quality in Lahore and several other districts of Punjab, with an analysis by the Environment Protection Agency (EPA) Punjab identifying a clear cross-border movement of polluted air into the province.
The EPA’s analysis for November 8–10, based on a combination of air-trajectory modelling, satellite observations and readings from Punjab’s air quality monitoring stations, indicates that pollution-laden air originating in India travelled deep into Punjab, contributing to a sharp increase in particulate matter concentrations and Air Quality Index (AQI) readings.
According to the air-trajectory analysis, back-trajectories recorded at an altitude of 100 metres at 6am on November 9 showed that around 50 per cent of Punjab was under the influence of air that had originated in India within the preceding 24 hours. Approximately 39 per cent of the province was affected by air masses that had crossed the border within the previous 12 hours.
The forward-trajectory modelling further indicated that air released across the international border on Diwali night could reach Lahore from Amritsar in approximately two hours. The same air movement was estimated to take around 12 hours to reach Faisalabad and 11 hours to reach Multan, demonstrating how transboundary pollution could affect cities located well inside Punjab and not merely those situated close to the border.
Satellite observations provided additional evidence of the movement of pollution across the region. NASA’s Visible Infrared Imaging Radiometer Suite (VIIRS) and Moderate Resolution Imaging Spectroradiometer (MODIS) data showed a continuous belt of haze extending across the international border on November 9.
The analysis also recorded a substantial increase in aerosol optical depth (AOD), an indicator of the concentration of airborne particles in the atmosphere. Between November 7 and 9, AOD readings over Amritsar increased from 0.44 to 2.63, while Lahore recorded a rise from 0.56 to 2.63 during the same period. The increase was observed to diminish eastward into India, further supporting the assessment of pollution movement towards Pakistan.
Readings from Punjab’s air quality monitoring network also revealed a distinct geographical pattern in Lahore, with particulate pollution increasing most sharply at monitoring stations closer to the eastern border.
Among Lahore’s monitoring stations, Wagah Border recorded the highest increase in PM2.5 concentrations, rising by 275 per cent and reaching its peak between 3am and 4am. In comparison, Safari Park, situated on the western side of the city, recorded an increase of just 15 per cent.
The east-to-west variation in particulate matter concentrations was consistent with the movement of pollution carried by easterly winds from across the border, according to the analysis.
Lahore’s overall AQI increased from 366 on November 8 to 440 on November 9, reaching its highest recorded value at 9am. The simultaneous rise in particulate pollution, satellite-observed haze and air-trajectory findings points towards a significant contribution from transboundary pollution during the period.
The EPA analysis, however, also highlights the importance of examining local emission sources alongside regional atmospheric conditions when assessing the causes of deteriorating air quality. The findings underline that air pollution is not confined by geographical boundaries and that meteorological conditions can transport pollutants across considerable distances within a relatively short period.
Separately, an analysis by the Space and Upper Atmosphere Research Commission (SUPARCO), based on NASA’s Fire Information for Resource Management System (FIRMS) satellite data, showed that the total number of fire detections in Punjab, Pakistan, declined by approximately 21 per cent between January 1 and November 9, 2026, compared with the corresponding period in 2025.
The reduction was particularly significant in high-confidence fire detections, identified through saturated thermal-band observations, which declined by approximately 43 per cent.
Nominal-confidence detections, representing thermal observations more than 15 degrees Kelvin above surrounding pixels, decreased by around 20 per cent, while low-confidence detections, involving temperature differences of less than 15 degrees Kelvin, fell by approximately 23 per cent.
The SUPARCO findings indicate an overall decline in satellite-detected fire activity across Punjab during the period under review, although the figures represent satellite fire detections rather than a direct measurement of crop-residue burning alone.
Together, the two assessments offer complementary insights into Punjab’s air pollution situation: while satellite and atmospheric modelling point to the impact of cross-border pollution during the Diwali period, the annual comparison of fire detections indicates a decline in detected fire activity within the province.
