Portugal. No ground monitor we can use is in this city, so these numbers are model estimates, not measurements.
≈7µg/m³
Good, estimated
Estimated PM2.5, 7-day average to 2026-09-30, about 0.4× the WHO 24-hour guideline. 30-day average ≈ 6 µg/m³.
Model estimate from the Copernicus Atmosphere Monitoring Service (CAMS), scaled by 0.64 to match 10 measured cities within 300 km over the last week. Adjusted this way, a single day lands within ×1.5 of what a monitor would read about two times in three: a guide, not a measurement. Not ranked on SmogRank's boards.
Last 30 days, estimated
Daily means, UTC days. Dashed line: WHO 24-hour guideline (15 µg/m³).