Abstract
The recovery of beaches following the destructive impact of storms is of significant economic, social and environmental value to coastal communities. This study investigates the recovery of a berm following removal by a storm at Narrabeen-Collaroy Beach, Australia using the unique deployment and remote operation of a Lidar mounted on the rooftop of a beachside building. Near-continuous (5Hz) subaerial profile and swash measurements were observed throughout the entire 2.5 month post-storm recovery period. The results provide new insight into the temporal progression of post-storm berm recovery, identifying three consecutive phases of immediate post-storm deposition, intermediate gradual recovery and final rapid recovery with the welding of intertidal sandbars. Significant berm growth was observed during the final phase with rates of subaerial volume deposition three times greater than those during initial phases. Relatively milder nearshore wave conditions as well as flatter intertidal gradients were found to distinguish rapid from more gradual recovery phases. Beachface progradation and berm aggradation during recovery are captured in detail by the high temporal resolution of the fixed Lidar data, providing insight into parameters governing berm recovery on microtidal, wave-dominated sandy coastlines.
Original language | English |
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Pages | 872-878 |
Number of pages | 7 |
Publication status | Published - 23 Jun 2017 |
Event | Australasian Coasts and Ports 2017 Conference - Cairns, Australia Duration: 21 Jun 2017 → 23 Jun 2017 |
Conference
Conference | Australasian Coasts and Ports 2017 Conference |
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Country/Territory | Australia |
City | Cairns |
Period | 21/06/17 → 23/06/17 |
Funding
This study is supported by the Australian Research Council (DP150101339) and the Coastal Processes and Responses Node of the OEH Climate Change Research Hub. Lidar swash data processing assisted by Daniel Howe, UNSW Sydney. LabVIEW software was developed by Katrina Taylor, EnvisEng. Wave and tide data were kindly provided by Manly Hydraulics Laboratory on behalf of the NSW Office of Environment and Heritage (OEH). Nearshore wave modelling and the composition of a lookup table was undertaken by Thomas Mortlock, Macquarie University. The first author is supported by an Australian Postgraduate Award.
Keywords
- Accretion
- Beach recovery
- Berm
- Lidar
- Narrabeen-Collaroy
ASJC Scopus subject areas
- Ocean Engineering