Worst air pollution Castanhal, today and tomorrow
Today (9 August): Air quality in Castanhal is good. AQI, PM2.5, PM10, NO2, O3, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 12:00 AM (O3: 19.4/100).
Tomorrow (10 August 2026): Air quality in Castanhal is fair. AQI worsens to fair; PM2.5 increases to fair; all other pollutants stay as today. Pollution peaks around 11:00 PM (PM2.5: 23.5/100). Airmine updates local air quality forecasts four times daily.
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Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team
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Castanhal's air quality reflects its position in the Pará lowland at the gateway to the northeastern Amazon region, with vehicle emissions from the BR-316 and the surrounding mixed agricultural and urban growth of this major Belém metropolitan satellite contributing local sources. Atlantic equatorial airflows generally provide background ventilation, while dry season burning from surrounding Pará Amazon deforestation generates intense PM2.5 episodes between July and November that dominate the regional air quality across the entire northeastern Pará corridor during the burning season.
Today - 9 August | Pollution peaks at 00:00
AQI:
Good
19.4/100
PM2.5 (fine particles):
Good
13.3/100
PM10 (coarse particles):
Good
6.1/100
NO2 (nitrogen dioxide):
Good
0.2/100
O3 (ozone):
Good
19.4/100
SO2 (sulfur dioxide):
Good
1.9/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
0.6/100
PM1 (ultrafine particles):
Good
4.2/100
Levels show the poorest local air quality during the day
Tomorrow - 10 August | Pollution peaks at 23:00
AQI:
Fair
23.5/100
PM2.5 (fine particles):
Fair
23.5/100
PM10 (coarse particles):
Good
9.4/100
NO2 (nitrogen dioxide):
Good
0.2/100
O3 (ozone):
Good
18.8/100
SO2 (sulfur dioxide):
Good
1.9/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
0.6/100
PM1 (ultrafine particles):
Good
15.4/100
Frequently Asked Questions
Is air quality bad in Castanhal right now?
On 9 August 2026, overall air quality in Castanhal is good. AQI is the main air quality indicator at 19.4/100. Pollution peaks around 12:00 AM (O3: 19.4/100).
Will air quality be worse tomorrow in Castanhal?
On 10 August 2026, air quality conditions in Castanhal will be worse than today, with AQI forecast at fair at 23.5/100. Pollution peaks around 11:00 PM (PM2.5: 23.5/100).
When is air pollution at its worst in Castanhal?
People in Castanhal tend to notice reduced air quality when native Amazon forest remnants and introduced urban trees pollen peaks, or because of vehicle emissions from the BR-316 and the surrounding mixed agricultural and urban growth of this major; a shift to wetter or windier weather typically brings noticeable relief.
Are air quality levels in Castanhal 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: 9 August 2026 at 20:27 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.
Disclaimer: Forecasts are provided for informational purposes only and should not be relied upon as medical advice. Actual pollen and air quality conditions may vary from the forecast. If you have allergies, asthma, or another medical condition, consult a healthcare professional. Please see our Terms of Service for important information about limitations of liability.
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