Lahore's air pollution a year-round problem intensified by winter, agricultural burning: report

LAHORE: Lahore’s fine particulate matter pollution remained above Pakistan’s prescribed standards for the past 12 months, including the relatively cleaner summer months, indicating that the city’s air pollution remained a year-round problem intensified by winter weather and seasonal agricultural burning, according to an analysis.

The report, titled ‘Lahore’s smog: The year-round baseline, and what changes in October ’, was released by the environmental monitoring project ‘Hamari Hawa’ on November 2 and prepared by its founder, Hammad Tariq.

It drew on ground-monitoring data, satellite observations and atmospheric reanalysis to examine pollution levels and possible sources around Lahore.

On Monday, air pollution in Lahore reached hazardous levels, with the Air Quality Index (AQI) crossing 530 and fine particulate matter (PM2.5) concentrations climbing to 343 micrograms per cubic metre.

According to the analysis, Lahore’s monthly average PM2.5 concentration remained above 35 micrograms per cubic metre from October 2025 to October 2026. Even in the city’s cleaner months, April to September 2026, monthly averages ranged from 40 to 59 micrograms per cubic metre, against the national annual standard of 15 micrograms per cubic metre.

The report used IQAir’s historical data, which aggregates readings from ground monitors across the city. It recorded a monthly average of 40 micrograms per cubic metre in June 2026, the lowest during the period, while averages from October 2025 to February 2026 ranged between 124 and 183 micrograms per cubic metre. October 2026 recorded 100 micrograms per cubic metre.

The report cautioned that the national limit of 35 micrograms per cubic metre is a 24-hour standard, whereas the monthly figures are monthly averages. The comparison therefore showed the persistence of pollution but does not establish how many individual days exceeded the daily limit.

The analysis identified a sharp seasonal decline in the height of the atmospheric layer into which pollutants can disperse as one of the factors behind the winter increase.

Using ERA5 atmospheric reanalysis data, it estimated that the average mixing height over Lahore falls from around 830 to 860 metres in May and June to about 400 metres in October and 260 metres in November. It declined further to around 190 metres in December.

A shallower mixing layer leaves less air available for pollutants to disperse, allowing concentrations near the ground to rise even without an increase in emissions, the report said.

According to the report, in an idealised comparison where emissions and other conditions remain unchanged, reducing the mixing layer to half or a third of its earlier depth could make smoke roughly two to three times more concentrated.

It also noted that Lahore’s average wind speed remained relatively light throughout the year, ranging from about 1.8 to 2.4 metres per second, and that October is not necessarily windier or calmer than September.

The report also examined satellite-detected heat spots on farmland around Lahore, which it classified as crop-associated detections after excluding locations near known kilns, dumps, industrial sites and towns.

Between October 15 and November 1, 2026, satellites recorded 781 such detections within 40 kilometres of central Lahore. Of these, 322 were in Sheikhupura district, 149 in India’s Tarn Taran district, 106 in Amritsar, 77 in Nankana Sahib, 62 in Lahore district and 50 in Kasur.

The analysis found that between 37 and 63pc of crop-associated satellite detections within 100 kilometres of Lahore on the Pakistani side occurred after November 1 in each of the seven seasons from 2019 to 2025.

It said the timing was significant because agricultural burning around the rice harvest coincided with the period when the atmospheric mixing layer becomes progressively shallower.

However, the report stressed that satellite heat detections do not confirm individual fires. A single field fire may generate several detections, while fires obscured by clouds or occurring between satellite passes may not be recorded. The figures also do not measure the area burnt or the quantity of pollution released.

The report said pollution sources operating throughout the year include vehicle exhaust, factories, brick kilns, power plants, generators, household fuels, open rubbish burning and dust. Some fine particles are also formed in the atmosphere through chemical reactions involving gases released by these sources.

Citing the Urban Unit’s 2023 Lahore emissions inventory, which was based on 2020–21 data, the report said that transport accounted for about 35pc of the city’s PM2.5 emissions, compared with 33pc from crop-residue burning, 29pc from waste burning and three per cent from industry.

It cautioned against interpreting the frequently quoted figure of 83pc for transport as its share of PM2.5. That figure covers all pollutants by weight and is dominated by carbon monoxide, it added.

A separate Punjab-wide Urban Unit inventory for 2020 estimated that heavy-duty vehicles and buses produced 55pc of road vehicles’ exhaust PM2.5, compared with 18pc from motorcycles. The report said the figures are provincial estimates and should not be treated as a direct measurement of Lahore’s current pollution.

It also identified 890 mapped brick kilns within 50 kilometres of central Lahore, including 196 within 25 kilometres.

The analysis further highlighted the difficulty of establishing how much pollution originates from within Pakistan and how much of it crosses the border. It cited estimates of the cross-border contribution to Lahore’s pollution ranging from 13 to 30pc based on figures from different studies and geographical areas.

It concluded that emissions inventories, ground-level monitoring and source-apportionment studies measure different aspects of air pollution and their percentages cannot be directly compared or converted into one another.

The report’s central finding was that the seasonal improvement in air quality does not mean Lahore has clean air during the rest of the year. It argued that persistent emissions form the baseline, while the shrinking atmospheric mixing layer and crop-residue burning add to pollution during the smog season.

Meanwhile, the Environment Protection and Climate Change Department (EPCCD) released a report stating Lahore recorded a 15pc net improvement across six major air pollutants during the first year of the Punjab government’s real-time air quality monitoring programme, while the city’s peak Air Quality Index (AQI) declined by 28pc in October 2026 compared to the corresponding period last year.

The department said the improvement reflected a reduction across six major atmospheric pollutants rather than a change in a single parameter, particularly fine particulate matter (PM2.5). Lahore also recorded no days in the hazardous AQI category, defined as an index above 300, during October 2026, against four such days in October 2025.

The findings were based on the first full year of real-time air quality monitoring and publicly available ground-based measurements. The government said the data provided an empirical basis for assessing the impact of its air pollution control measures and developing targeted interventions.

According to the EPCCD, the first reading on Punjab’s real-time air quality portal was published on Oct 1, 2025, with an initial network of 30 regulatory-grade monitoring stations. The network has since expanded to 59 stations, which continuously measure six air pollutants and seven meteorological parameters.

The government plans to increase the number of monitoring stations to 100 during the 2025–26 period to strengthen its capacity for monitoring ambient air quality across the province, it said.

The department maintained that the expanded network had enabled authorities to make more informed decisions through accurate, ground-based measurements, particularly in contrast to assessments relying on low-cost, non-regulatory sensors and satellite-derived models.

The EPCCD also highlighted the role of meteorological conditions in interpreting the improvement.

According to official Pakistan Meteorological Department (PMD) statistics, Lahore received 50pc less rainfall in October 2026 than in October 2025, indicating that the improvement was recorded despite relatively drier conditions.

Another important factor in assessing air pollution is the atmospheric boundary layer, also known as the mixing height, which determines the volume of air available to dilute and disperse pollutants.

The department said ground-based measurements conducted by the Space and Upper Atmosphere Research Commission (Suparco) using a ceilometer in Lahore showed an increase of only 10 metres in the minimum mixing layer height during the comparison period.

This finding was presented in contrast to a 25-metre increase cited by the Pakistan Air Quality Initiative (PAQI). The EPCCD, in its report, questioned the reliability of the latter assessment, arguing that ground-based instruments provided more appropriate measurements for evaluating local air quality interventions.

The department also referred to peer-reviewed research published in January 2026, which identified systematic biases of between 200 and 500 metres in ERA5 reanalysis data over the monsoon region. It said such model-derived products were useful for regional research but had limitations when used to assess the local impact of air pollution control policies.

Alongside monitoring infrastructure, the Punjab government has been implementing a multi-sectoral air pollution reduction strategy targeting transport, industrial emissions, brick kilns and agricultural burning.

In the transport sector, the government has introduced 612 electric buses, while also providing electric bikes and improving traffic management to reduce emissions from conventional vehicles. The department said around 500,000 vehicles had undergone emissions testing, while more than 800 legal notices had been issued to heavy transport vehicles over emissions and fitness certification requirements.

The government aimed to expand its electric bus fleet to 3,000 vehicles as part of its clean mobility strategy, the report said.

It further noted that industrial compliance had also been strengthened through the Environment Protection Force — responsible for monitoring emissions, fuel quality and fugitive dust control systems at more than 600 sites across Punjab. The department said industries emitting excessive smoke without adequate emission-control systems, as well as units using unauthorised fuels, were not being allowed to operate.

The government has also imposed a complete ban on the operation of tyre pyrolysis plants and the use of carbon powder as industrial fuel, citing concerns over hazardous emissions, it noted.

Agricultural emissions, particularly those caused by the burning of crop residue, remain another major component of the anti-smog strategy. The EPCCD said field-level stubble-burning incidents had declined by one-third during the first year after the government provided 10,000 super seeders to farmers through targeted subsidies.

The government plans to increase the number of subsidised super seeders to 25,000 and introduce additional mechanised solutions, including Kubota harvesters and stubble balers, to discourage open burning and facilitate the use of crop residue as industrial fuel, it said.

The department also attributed part of the reduction in emissions to changes in the energy and industrial sectors. According to the latest statistics from the Ministry of Energy’s Petroleum Division, the annual compound growth rate of coal consumption declined by 14.2pc.

Meanwhile, more than 95pc of brick kilns in Punjab have adopted the zigzag technology, which the department said had helped reduce coal consumption and emissions from the brick-making sector.

The EPCCD said coordination among government departments and stakeholders, coupled with regulatory enforcement, cleaner transport initiatives and the expansion of ground-based monitoring, had contributed to the progress recorded during the first year.

It maintained that the 2026 findings provided a baseline for measuring future improvements and refining pollution-control interventions, while emphasising that sustained enforcement and a transition towards cleaner fuels and technologies would remain essential to protecting public health and improving air quality in Lahore and other parts of Punjab.