Abstract
A key limitation to further understanding of storm induced beach erosion and the development of accurate predictive coastal
erosion models is the paucity of field scale data collected within a short period of time of an erosion event. The collection of this
data is made difficult by the challenging coastal environment in addition to the episodic nature of coastal storms. This thesis
introduces the method of rapid-response airborne lidar that was developed and tested in order to collect such data. A light
aircraft mounted lidar system performed surveys with different flight configurations at the Narrabeen Embayment and the
ability to resolve beach topography and derived coastal change were investigated. This was compared to the standard survey
method of a GPS equipped ATV, with the airborne lidar surveys able to perform beach surveys at an accuracy on par with the
ATV method, and able to derive a shoreline position and beach volume with a root means squared error of 0.94 m and 3.89 m3/
m when compared the ATV method.
In order to reduce uncertainty as to the drivers of storm induced beach erosion, a nearshore spectral wave model was developed
to transform the offshore deep water wave climate into a nearshore wave climate at 75 different locations within Narrabeen
Embayment. This model was tested against nearshore wave observations taken from two wave rider buoys located within the
embayment.
The rapid-response airborne lidar capability was deployed immediately before, during and immediately after an East Coast Low
storm event at the Narrabeen Embayment, representing an almost daily dataset of the rapidly evolving morphology. This survey
data, which indicated considerable alongshore variation in the dune erosion response to the storm, was then combined with the
measured and modelled hydrodynamic data to test several simple dune erosion models. The effect of forcing data resolution and
alongshore averaging was also investigated. A modification to one of the models was presented, it showing modest
improvement compared to the other models, being able to explain 67% of the observed dune erosion across the entire
embayment.