Disaggregate GIS modelling to track spatial change: exploring a decade of commuting in South East Queensland, Australia

Changes in commuting dynamics are explored for a large geographical region using journey-to-work (JTW) data derived from two censuses (1996 and 2006). The main thrust is concerned with the identification of geographic patterning of commuting distance and flow (i.e. the number of people travelling from region i to region j) coupled with the changes in these patterns over the decade to 2006. GIS-based methods are employed to first calculate the average commuting distance and second to map the degree of self-containment (i.e. people living and working within the same area) at a fine spatial scale. Through a quantitative analysis of JTW patterns over the two census datasets, the results are linked to current planning debates regarding urban spatial policies that seek to reduce commuting distances. Specific attention is given to address: (1) spatial variation in changes in commuting distance across the study region between 1996 and 2006; and (2) whether jobs-housing balanced development reduced commuting distances over the decade. Results indicate that the spatial patterns of commuting have changed little over the 10 year period and the change in commuting distance presented strong relationships to the change in jobs-housing ratio (JHR) at local areas. Implications for urban policy include the need for improved industry-occupation matching and consideration of planned employment decentralisation.