Purnia vs Siwan
Side-by-side air quality comparison between Purnia and Siwan.
Live AQI from Open-Meteo CAMS (~45 km global model, updated hourly). Multi-year history from CPCB station data via aqinow.co pipeline (2016–2024, station-level daily records).
AQI Comparison
Pollutant-level comparison (PM2.5, PM10, O3, NO2, SO2, CO)▾
| Pollutant | Purnia | Siwan |
|---|---|---|
| PM2.5(µg/m³) | 105.90 | 114.60 |
| PM10(µg/m³) | 109.00 | 125.70 |
| NO₂(µg/m³) | 25.20 | 44.50 |
| SO₂(µg/m³) | 20.10 | 15.40 |
| O₃(µg/m³) | 67.00 | 54.00 |
| CO(µg/m³) | 707.00 | 761.00 |
CPCB Multi-Year History (2016–2024)
Summary
Overview
In 2024, Purnia averaged an AQI of 133 while Siwan averaged 148 — a 15-point (11%) gap, with Siwan the more polluted and Purnia the cleaner of the two. On 660 days when both cities reported, Purnia was cleaner on 366 of them; the average daily gap was 63 AQI points.
Seasonality & days
Both cities see their worst air in January on average. Purnia logged 3.7% Severe days and 33.699999999999996% Good-or-Satisfactory days; Siwan was 5.2% Severe and 17.7% Good-or-Satisfactory. Longest clean-air streaks: Purnia 14 days, Siwan 13 days.
Year-over-year progress
Purnia has improved by 163 AQI points (55.1%) from 2021 to 2024; Siwan has improved by 184 AQI points (55.4%) over the same window. The worst recorded day for Purnia reached AQI 460 at Mariam Nagar (BSPCB) on 2022-12-15; Siwan hit AQI 488 at Chitragupta Nagar (BSPCB) on 2022-12-30.
Station-level disparity
Purnia spans 1 CPCB stations with a 0-point spread (min 176, max 176); Siwan spans 1 stations with a 0-point spread (min 197, max 197).
Verdict
🏆 Purnia has better air quality with an AQI of 253 compared to Siwan's 282.