Air Quality in West Bengal
Air Quality Index monitoring across major cities in West Bengal — PM2.5, PM10, NO2, SO2, and other pollutants.
Air quality in West Bengal follows geography almost perfectly. Industrial belts (Howrah, Asansol) and dense urban cores (Kolkata) spend much of winter above the 'unhealthy' AQI threshold. Hill towns like Darjeeling stay near WHO limits year-round. And the seasonal pattern is stark — winter is always the worst, monsoon the best.
Key figures & data tables
This page tracks daily air quality across 10 West Bengal cities — Asansol, Baharampur, Bardhaman, Durgapur, Haldia, Howrah, Kharagpur, Kolkata, Malda, Siliguri — from 15,600daily observations. The state’s worst performer is Bardhaman at an average AQI of 270; the cleanest is Siliguri at 194, against a national average of 153.
Seasonality dominates everything else: Winter (Dec-Feb) averages AQI 341, Post-Monsoon (Oct-Nov) averages AQI 282, Pre-Monsoon (Mar-May) averages AQI 249, Monsoon (Jun-Sep) averages AQI 163. Winter is consistently three to four times worse than the monsoon, when rain scavenges particulates out of the air.
On particulates, Bardhaman averages PM2.5 of 63 µg/m³ and PM10 of 80.3µg/m³ — against the WHO annual guideline of 5 µg/m³ for PM2.5 and India’s own national ambient standard of 40 µg/m³. Nitrogen dioxide averages 18.1 µg/m³ and sulphur dioxide 18.5 µg/m³.
The rows behind the charts above — 3 tables
›Average air quality index by West Bengal city(10 rows)
Pre-aggregated from data/processed/aqi_wb.json (daily rows). Saves ~2.7 MB over the wire for /environment. Data refreshed daily from Open-Meteo Air Quality; CPCB for reference standards.
| City | Average AQI | PM2.5 (µg/m³) | PM10 (µg/m³) | NO₂ (µg/m³) | SO₂ (µg/m³) |
|---|---|---|---|---|---|
| Bardhaman | 270 | 63 | 80.3 | 18.1 | 18.5 |
| Howrah | 264 | 57.7 | 74.6 | 22.9 | 21.4 |
| Kolkata | 264 | 57.7 | 74.6 | 22.9 | 21.4 |
| Baharampur | 262 | 59.6 | 76.9 | 19.8 | 18.2 |
| Durgapur | 258 | 58.7 | 77.1 | 30.4 | 53.8 |
| Malda | 246 | 54.4 | 70.9 | 14.4 | 12.6 |
| Asansol | 241 | 53.9 | 71.8 | 28 | 47.9 |
| Kharagpur | 235 | 51.6 | 66.6 | 11.5 | 18.1 |
| Haldia | 228 | 48.1 | 63 | 11.9 | 13.6 |
| Siliguri | 194 | 39.2 | 51.3 | 12.9 | 5.3 |
›Seasonal air quality in West Bengal(4 rows)
| Season | Average AQI |
|---|---|
| Winter (Dec-Feb) | 341 |
| Post-Monsoon (Oct-Nov) | 282 |
| Pre-Monsoon (Mar-May) | 249 |
| Monsoon (Jun-Sep) | 163 |
›Pollutant concentrations by West Bengal city (µg/m³)(10 rows)
| City | PM2.5 | PM10 | NO₂ | SO₂ |
|---|---|---|---|---|
| Bardhaman | 63 | 80.3 | 18.1 | 18.5 |
| Howrah | 57.7 | 74.6 | 22.9 | 21.4 |
| Kolkata | 57.7 | 74.6 | 22.9 | 21.4 |
| Baharampur | 59.6 | 76.9 | 19.8 | 18.2 |
| Durgapur | 58.7 | 77.1 | 30.4 | 53.8 |
| Malda | 54.4 | 70.9 | 14.4 | 12.6 |
| Asansol | 53.9 | 71.8 | 28 | 47.9 |
| Kharagpur | 51.6 | 66.6 | 11.5 | 18.1 |
| Haldia | 48.1 | 63 | 11.9 | 13.6 |
| Siliguri | 39.2 | 51.3 | 12.9 | 5.3 |