SmogRank / Taiwan / Taiwan / Guanshan
Guanshan, month by month
Guanshan has a measured daily mean on 838 days since 8 February 2024. Its worst month was April 2026, at 59 US AQI (13.6 µg/m³), 640th of 2,941 cities on that month's world ranking. Its cleanest was July 2024, at 16 US AQI (2.8 µg/m³).
Every month since 2024
The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales
Months without a mean, and why
5 months
| Month | Why |
|---|---|
| Nov 2025 | 12 of 30 days measured; a month needs 21. The others: 17 with no readings from the monitor, 1 with readings for part of the day (a day needs 18 hours). |
| Oct 2025 | 10 of 31 days measured; a month needs 22. The others: 21 with no readings from the monitor. |
| Aug 2025 | 6 of 31 days measured; a month needs 22. The others: 24 with no readings from the monitor, 1 with readings for part of the day (a day needs 18 hours). |
| Jul 2025 | No day measured. The others: 30 with no readings from the monitor, 1 with readings for part of the day (a day needs 18 hours). |
| Feb 2024 | 6 of 29 days measured; a month needs 21. The others: 13 with no readings from the monitor, 3 with readings for part of the day (a day needs 18 hours). |
A day counts once 18 hours of it are measured; a month needs 70% of its days.
Guanshan's worst months
| Month | US AQI | World rank |
|---|---|---|
| April 2026 | 5913.6 µg/m³ | 640thof 2,941 |
| April 2025 | 5712.3 µg/m³ | 728thof 2,951 |
| April 2024 | 5410.9 µg/m³ | 884thof 2,520 |
| January 2025 | 5410.8 µg/m³ | 869thof 2,474 |
| March 2024 | 529.5 µg/m³ | 495thof 1,698 |
| January 2026 | 498.9 µg/m³ | 1,266thof 2,617 |
Monthly means over the days measured; finished months only. World rank: its place on that month's world ranking of every city with enough days. Each month opens that ranking.
Guanshan's worst days
| Day | US AQI |
|---|---|
| 11 Apr 2026 | 7823.4 µg/m³ |
| 1 Jan 2025 | 7522.0 µg/m³ |
| 10 Apr 2026 | 7421.6 µg/m³ |
| 17 Apr 2026 | 7421.4 µg/m³ |
| 13 Apr 2025 | 7321.1 µg/m³ |
| 10 May 2026 | 7321.0 µg/m³ |
| 4 Apr 2026 | 7320.7 µg/m³ |
| 2 May 2024 | 7220.5 µg/m³ |
| 12 Apr 2026 | 7220.4 µg/m³ |
| 4 Apr 2024 | 7220.3 µg/m³ |
Daily means, the highest since 8 Feb 2024; the WHO's daily guideline is 15 µg/m³. Each date opens that day's world ranking, and each episode the bad-air spell it was part of.
Use this history
SmogRank, PM2.5 monthly and daily means, Guanshan, Taiwan, 8 Feb 2024 – 12 Oct 2026. Monitor data from Taiwan's Ministry of Environment via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/tw/guanshan/history (accessed 12 Oct 2026).
You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.
Guanshan now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 22:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).