Ghaziabad, Greater Noida and Noida top national pollution chart with worse to come

Air pollution

A thick, noxious haze clung stubbornly to the National Capital Region (NCR) on Wednesday, cementing its status as India’s epicentre of pollution even as the contribution from seasonal farm fires saw a dramatic decline.

Data from the Central Pollution Control Board (CPCB) revealed that the four most polluted cities in the country were all within the NCR, with Ghaziabad leading the chart with a severe Air Quality Index (AQI) of 422.

Greater Noida and Noida followed closely with AQIs of 420 and 409, respectively, also placing them in the “severe” category. Delhi itself hovered perilously close to the mark, recording an AQI of 392, classified as “very poor” but missing the “severe” threshold by a mere nine points.

The primary pollutants across the region remained PM2.5 and PM10, particulate matter small enough to penetrate deep into the lungs and cause significant health issues.

The concentration of toxic air in the NCR was starkly illustrated by the fact that all ten of India’s most polluted cities on Wednesday were part of the capital’s sprawling metropolitan area, according to the CPCB data. This is part of a persistent trend; an analysis of the first 19 days of November shows NCR towns have topped the national pollution list on 14 occasions.

With meteorological conditions expected to remain unfavourable, official forecasts offer little hope for relief. The Centre’s Air Quality Early Warning System (EWS) for Delhi predicted the capital’s AQI would remain “very poor” until Friday, before deteriorating to “severe” on Saturday.

The outlook for the subsequent six days indicates air quality will likely oscillate between “severe” and “very poor,” a forecast corroborated by the Indian Institute of Tropical Meteorology (IITM).

A significant shift noted by analysts is the rapidly diminishing role of stubble burning. Data from the Decision Support System (DSS) showed its contribution to Delhi’s PM2.5 plummeted to just 3.88% on Wednesday, down from 16.13% on Monday. This decline was reflected in farm fire counts, with Punjab and Haryana reporting only 16 and 11 such incidents respectively.

In the absence of significant agricultural smoke, local emissions have emerged as the dominant problem. The DSS data identified Delhi’s transport sector as the leading contributor to PM2.5 pollution, accounting for 18.03% of the harmful particulates. Emissions from residential areas and industries followed at 4.65% and 4.23% respectively.

Sunil Dahiya, founder and lead analyst at the think-tank Envirocatalysts, reportedly explained that the NCR’s high population load and geographical positioning create a perfect storm for pollution. He attributed the crisis to “high consumption of energy, high vehicular load, waste generation and lots of industries which all generate a high emission load,” compounded by low winds and the region’s location in a corridor between the Aravallis and Himalayas that traps polluted air.

The region is already under Stage-3 restrictions of the Graded Response Action Plan (GRAP), which includes a ban on non-essential construction and the operation of certain categories of private vehicles. With temperatures dipping below seasonal norms and wind speeds remaining low, the suffocating blanket of pollution shows no sign of lifting, leaving millions to breathe what remains the country’s most toxic air.