Air Quality Forecasting - also refered as 'Atmospheric Dispersion Modeling' (wikipedia) is the art of simulating how air pollutants (eg PM2.5 or Ozone) disperse is the ambient atmosphere. The result of the simulation gives the ambient concentration for each air pollutants, from which the Air Quality Index can be calculated.
There are dozens of dispertion models, and many universities and institutions arround the world are running one or several of them for different regions (eg Europe, Continental US, Asia ...). Below is the a non-exaustive and selected list of few models which are beeing used for providing Air Quality forecast on the "World Air Quality Index" project.
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