Worst air pollution Rio Tinto, today and tomorrow
Today (21 July): Air quality in Rio Tinto is medium. AQI and O3 are medium; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 2:00 PM (O3: 40.1/100).
Tomorrow (22 July 2026): Air quality in Rio Tinto is fair. AQI worsens to fair; O3 increases to fair; all other pollutants stay as today. Pollution peaks around 3:00 PM (O3: 39.9/100). Airmine updates local air quality forecasts four times daily.
For long term forecasts and maps, see the Airmine app
Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team
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Rio Tinto's air quality reflects the greater Porto metropolitan area's northern Gondomar-Valongo industrial corridor on the Tinto river, with vehicle traffic on the A41 motorway and surrounding industrial and residential character contributing elevated NOₓ and PM2.5. Atlantic westerlies generally provide maritime ventilation, while the surrounding Porto metropolitan hills create topographic variation and the industrial character maintains moderate but persistent emission levels above the Portuguese rural background throughout the year.
Today - 21 July | Pollution peaks at 14:00
AQI:
Medium
40.1/100
PM2.5 (fine particles):
Good
14.5/100
PM10 (coarse particles):
Good
11.8/100
NO2 (nitrogen dioxide):
Good
5.5/100
O3 (ozone):
Medium
40.1/100
SO2 (sulfur dioxide):
Good
0.4/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
7.3/100
PM1 (ultrafine particles):
Good
12.8/100
Levels show the poorest local air quality during the day
Tomorrow - 22 July | Pollution peaks at 15:00
AQI:
Fair
39.9/100
PM2.5 (fine particles):
Good
13.0/100
PM10 (coarse particles):
Good
9.7/100
NO2 (nitrogen dioxide):
Good
6.0/100
O3 (ozone):
Fair
39.9/100
SO2 (sulfur dioxide):
Good
0.5/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
5.3/100
PM1 (ultrafine particles):
Good
8.6/100
Pollen forecast in Rio Tinto
View pollen forecastFrequently Asked Questions
Is air quality bad in Rio Tinto right now?
On 21 July 2026, overall air quality in Rio Tinto is medium. AQI is the main air quality indicator at 40.1/100. Pollution peaks around 2:00 PM (O3: 40.1/100).
Will air quality be worse tomorrow in Rio Tinto?
On 22 July 2026, air quality conditions in Rio Tinto will be worse than today, with AQI forecast at fair at 39.9/100. Pollution peaks around 3:00 PM (O3: 39.9/100).
When is air pollution at its worst in Rio Tinto?
Reduced air quality in Rio Tinto is most likely when highland landscape oak and eucalyptus pollen peaks, alongside periods of vehicle traffic on the A41 motorway and nearby industrial and residential character; cooler, breezier weather later in the year tends to bring things back down.
Are air quality levels in Rio Tinto based on measurements or forecasts?
It is forecasts derived by downscaling forecasts provided by EU’s Copernicus Atmosphere Monitoring Service (CAMS) by taking into account local conditions such as traffic patterns. CAMS bases its forecast on satellite measurements of particles and chemical compounds in the atmosphere. Airmine’s services were developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team.
Why doesn’t the forecast always reflect wildfire impacts?
Airmine’s forecast uses CAMS (Copernicus Atmosphere Monitoring Service) as its background atmospheric model. While CAMS includes wildfire emissions, these are derived from satellite observations and are not available in real time. During rapidly evolving wildfire events, there may therefore be a delay before increased emissions are incorporated into the model. As a result, the forecast may temporarily underestimate PM₂.₅ and other pollutants associated with wildfire smoke.
During rapidly evolving wildfire events, CAMS may lag by approximately 1–2 days before increased wildfire emissions are fully represented, which can lead to temporary underestimation of PM₂.₅ concentrations in Airmine’s forecast.
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Data provided by Airmine — Last update: 21 July 2026 at 16:20 CEST (Data is updated four times daily.)
This forecast is produced independently using Airmine's own atmospheric data and models.
Unless explicitly made clear, the content on this site has not been paid for by external organisations and is Airmine's sole responsibility.
For long term forecasts and maps, see the Airmine app