BEACH SLOPES FROM SATELLITE-DERIVED SHORELINES

Kilian Vos,Ian L Turner,Mitchell D Harley,Kristen D Splinter,Andrew Walker

doi:10.9753/icce.v36v.sediment.36

Abstract

The slope of the beach face is a critical parameter for coastal scientists and engineers studying sandy coastlines. However, despite its importance for coastal applications (engineering formulations, coastal flood modelling, swimming safety), it remains extremely difficult to obtain reliable estimates of the beachface slope over large spatial scales (hundreds to thousands of km of coastline). This presentation describes a new method to estimate the beach-face slope exclusively from space-borne observations: shoreline positions derived from publicly available optical imaging satellites and tide heights from satellite altimetry. This new technique is first validated against field measurements and then applied across hundreds of beaches in eastern Australia and California, USA (data available at http://coastsat.wrl.unsw.edu.au/).Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/U9zMbFX4gPk

Highlights

The slope of the beach face is a critical parameter for coastal scientists and engineers studying sandy coastlines as it can dictate the way a beach interacts with the incoming ocean waves
The satellitederived slope estimates are compared against field measurements at eight locations spanning a range of tidal regimes and sediment grain sizes, resulting in a good agreement (R2= 0.93) between satellite and in situ estimates. To demonstrate how this technique can be applied over large spatial scales, the automated algorithm is applied across hundreds of beaches in eastern Australia and California, USA
To demonstrate how this technique can be applied over large spatial scales, the automated algorithm is applied across hundreds of beaches in eastern Australia and California, USA (data available at http://coastsat.wrl.unsw.edu.au/)