Air quality modelling
Air quality is a major environmental issue in many areas. When meteorological and emissions data are available for a region, its air quality levels can be modelled based on different scenarios, such as:
- the formation of photochemical smog;
- the impact of population growth; or
- increased motor vehicle use.
The air quality models are validated by comparing predicted pollutant levels with observed data.
Air quality models are an important tool for managing air quality. They can be used to predict the impact of urban planning decisions, such as the placement of roads, and the location or expansion of residential and industrial areas. The department is developing urban airshed models to investigate the air quality in major industrial and population centres within Queensland. Airshed models are currently being upgraded for the south-east Queensland region and Gladstone.
Models are usually formulated as mathematical models which describe the physical processes and features of a physical system in mathematical terms. This means that even the most complex models will always be an approximate representation of the actual situation.
One of the main benefits of models is that they can be used to predict particular occurrences or phenomena that we may not be able to identify through observations. For instance, a model may show that a threshold concentration of a particular pollutant can trigger an air pollution episode.
Modelling of occurrences such as photochemical smog is a complex process. Concentrations of ozone (one of the major components of photochemical smog) and emissions of other pollutants are commonly used to model air quality situations.
Meteorological data, such as wind speed and direction, and photochemical reactions between pollutants are combined with data from a pollutant emissions inventory for a region to model the processes that occur in the atmosphere.
The findings of the model can be used to support strategies to manage the emissions from pollution sources if the causes of pollution are known and the consequences of exceeding the threshold concentration are detrimental.
Last updated: 18 January 2008