Photochemcial modelling studies using TAPM - CTM.

Regional photochemical modelling is complex and relies on good interpretation of meteorology, emissions and the chemical reactions to ensure a reliable outcome. Katestone has been working with CSIRO since 2005, helping beta-test the latest CSIRO photochemical transport model, TAPM-CTM. The model is now publically available and the team at Katestone has used the model on projects in Brisbane and Sydney.

TAPM-CTM can be used to determine the contribution that a facility may have on the overall ozone levels in an airshed and can also be used as a management tool to determine the best management control strategies. For example, TAPM-CTM can predict the impact that emission control strategies may have on the overall ground-level concentrations of ozone.

Katestone has worked for several major power generators to investigate the potential impact that existing or proposed future Power Stations may have on the ozone levels in major populated areas. By modelling scenarios with and without the Power Station sources it is possible to determine the contribution that the Power Station has on levels of ozone and oxides of nitrogen.

With the speed of computers ever increasing we now have the capability to run TAPM-CTM for seasonal evaluations, allowing analysis of ozone statistics rather than just peak ozone days. TAPM-CTM was recently used by Katestone to assess the potential impact of future urban growth on the ozone exposure in the greater Brisbane region. From this we determined regions in South East Queensland with low (noted as light blue in the figure below), medium (mid-blue) and high potential (red) ozone risk, based on frequency of ozone exposure and population density. This work is presented in our paper at the 2007 IUAPPA conference.

This figure presents a summary of the potential ozone exposure risk for the regions within Southeast Queensland based on TAPM-CTM modelling undertaken by Katestone Environmental. The red regions correspond to high levels of ozone exposure and high future population. The mid-blue regions correspond to areas with high exposure levels of ozone but relatively low population.

If these regions are to be considered as future population growth areas, monitoring and more extensive modelling studies should be undertaken to ensure that future populations are not subjected to high levels of ozone.

The light blue regions correspond to areas with low ozone exposure as well as relatively low population. These areas are the preferred regions for future population expansion from an air quality perspective (Katestone Environmental, 2007).