Seven case study locations (Keep, Daly, Roper, McArthur, Flinders, and Gilbert River estuaries, and Darwin Harbour) were used to test the utility of the Australian Landsat data archive in the Digital Earth Australia analysis platform for characterising and monitoring the condition and change in coastal habitats. A suite of analyses was undertaken including: assessing the extent of different coastal habitats, detecting coastal change including change in mangrove communities, and the distribution of intertidal areas. The work was successful in: (a) generating baseline information for the case study areas; and, (b) developing valuable monitoring tools for future use.
Intertidal areas were identified using the DEA archive based on modelled tide height that occurred at the time of image acquisition. This analysis utilises an advanced image classification scheme that enables viewing of coastal regions at selected tide stages. In this approach, composite images of coastal regions over varying stages of the tide and varying time periods are generated as a way of showing coastal change. Furthermore, this tidally attributed archive of coastal imagery enables mapping of intertidal extents, which effectively characterises the topography of intertidal zones. This project looked specifically at the effectiveness of mapping changes in mangrove extent over the past 30 years in the nominated priority estuaries.