Brazilian Air Quality Forecast

Glossary
Air Quality Index
Air Quality Index
The AQI is an index for reporting daily air quality. The Air Quality Index, available on this web site, are colour coded, as defined by AirNow, and follow the EPA guidelines. It tells you how clean or polluted your air is, and what associated health effects might be a concern for you. The AQI focuses on health effects you may experience within a few hours or days after breathing polluted air.
Air Quality Index Levels of Health Concern Numerical
Value
Meaning
Good 0 to 50 Air quality is considered satisfactory, and air pollution poses little or no risk
Moderate 51 to 100 Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.
Unhealthy for Sensitive Groups 101 to 150 Members of sensitive groups may experience health effects. The general public is not likely to be affected.
Unhealthy 151 to 200 Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects.
Very Unhealthy 201 to 300 Health warnings of emergency conditions. The entire population is more likely to be affected.
Hazardous 301 to 500 Health alert: everyone may experience more serious health effects
Nitrogen dioxide (NO2)
Nitrogen oxides, particularly nitrogen dioxide, are emitted from high temperature combustion in e.g. transport and power generation, and are also produced during thunderstorms by lightning. They can be seen as a brown haze above or downwind of cities. Nitrogen dioxide (NO2) It is one of several nitrogen oxides and plays a key role in atmospheric chemistry.
Particulate matter (PM)
Particulate matter is a complex mixture of particles in the atmosphere. They originate from various sources and present a very large diversity of size, physical and chemical composition. Besides direct emission, particles can form through chemical reactions in the atmosphere from ammonia, sulfur dioxide, nitrogen oxides and hydrocarbons. PM10 and PM2.5 refer to particles with a diameter smaller than 10 and 2.5 ┬Ám, respectively. Particles of these size ranges are small enough to penetrate deep into the lungs and so potentially pose significant health risks. The principal source of airborne PM10 and PM2.5 matter in Brazilian cities is road traffic, particularly from heavy-duty diesel-powered vehicles.
Ozone (O3)
Tropospheric ozone (O3) is not emitted directly into the atmosphere by car engines or by industrial operations. Ozone is formed in the atmosphere through a chain of reactions involving hydrocarbons and nitrogen oxides in the presence of sunlight. The hydrocarbons derive mostly from vegetation, combustion and solvent use. Nitrogen oxides originate mainly from fuel combustion. The ozone formation occurs mostly downwind of large source areas for nitrogen oxides, e.g. urban areas. The role of ozone in the atmosphere is twofold, ozone has both a global impact on the climate as a GHG and an impact on air quality in the boundary layer. Ozone smog events have adverse effects on vegetation materials and human health.
Sulphur dioxide (SO2)
Sulphur dioxide (SO2)