Kollam vs Siwan
Side-by-side air quality comparison between Kollam 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 | Kollam | Siwan |
|---|---|---|
| PM2.5(µg/m³) | 4.70 | 112.50 |
| PM10(µg/m³) | 7.20 | 127.60 |
| NO₂(µg/m³) | 4.00 | 56.00 |
| SO₂(µg/m³) | 1.50 | 14.90 |
| O₃(µg/m³) | 31.00 | 15.00 |
| CO(µg/m³) | 91.00 | 865.00 |
CPCB Multi-Year History (2016–2024)
Summary
Overview
In 2024, Kollam averaged an AQI of 84 while Siwan averaged 148 — a 64-point (76%) gap, with Siwan the more polluted and Kollam the cleaner of the two. On 670 days when both cities reported, Kollam was cleaner on 599 of them; the average daily gap was 123 AQI points.
Seasonality & days
Both cities see their worst air in January on average. Kollam logged 0% Severe days and 81% Good-or-Satisfactory days; Siwan was 5.2% Severe and 17.7% Good-or-Satisfactory. Longest clean-air streaks: Kollam 65 days, Siwan 13 days.
Year-over-year progress
Kollam has improved by 2 AQI points (2.3%) from 2020 to 2024; Siwan has improved by 184 AQI points (55.4%) over the same window. The worst recorded day for Kollam reached AQI 272 at Polayathode Kollam (PCB) on 2024-04-06; Siwan hit AQI 488 at Chitragupta Nagar (BSPCB) on 2022-12-30.
Station-level disparity
Kollam spans 1 CPCB stations with a 0-point spread (min 84, max 84); Siwan spans 1 stations with a 0-point spread (min 197, max 197).
Verdict
🏆 Kollam has better air quality with an AQI of 8 compared to Siwan's 275. That's a significant difference of 267 points.