Geospatial Assessment of Reef Island Shoreline Dynamics: Mapping, Monitoring and Modelling

Low-lying reef islands are highly dynamic geomorphological landforms that respond to changes in environmental boundary conditions through movements in shoreline position. The question of whether shoreline displacements indicate eroding or accreting islands and, consequently, island stability or vulnerability is a critical research challenge in response to sea-level rise and other climate-change related issues in the twenty-first century. Most studies of reef island change focus on atoll settings and adopt twodimensional change assessments that focus on quantifying spatial and temporal variation in shoreline positions, without exploring or identifying environmental, physical or biological drivers of these changes. This thesis demonstrates some different tools and geospatial analyses to expand on existing assessments of shoreline change using a range of mapping, monitoring and modelling techniques. These go beyond the quantification of shoreline changes to explore underlying drivers of such changes on reef islands.