A geographically explicit global mass balance model of chemical fate

The objective of this thesis is to develop and apply a global mass balance model of chemical fate which has applications to both single and multi-species types of chemicals. The parameterization and development of a coarsely segmented (25 region) geographically explicit global mass balance model are presented. The historical global fate of alpha-hexachlorocyclohexane is investigated, including both steady state and dynamic approaches. The transport of chemical to the Arctic Ecosystem is a dominant focus. An exploration of the utility of various interpolation methods to explore the distribution of a chemical within North America and a single global region is undertaken and recommendations made on the integration of these interpolation methods with large-scale modelling projects. A novel methodology for modelling multi-species chemicals such as mercury is presented and a framework for integrating this approach with the existing geographically explicit global model is described. The use of spatial statistics in the segmentation and parameterization of environmental models is advocated. The integration of the multi-species approach with geographically explicit models of various scales would provide a framework by which the fate of chemicals such as mercury could be assessed and remediation strategies for present contamination be investigated through models. This framework would be especially useful in the determination of the risk to sensitive ecosystems such as the Arctic by emissions of a wide variety of chemicals.