Water 2017, 9(2), 121; https://doi.org/10.3390/w9020121
The June 2016 Australian East Coast Low: Importance of Wave Direction for Coastal Erosion Assessment
1
Risk Frontiers, Macquarie University, North Ryde, NSW 2109, Australia
2
Marine Climate Risk Group, Department of Environmental Sciences, Macquarie University, North Ryde, NSW 2109, Australia
*
Author to whom correspondence should be addressed.
Academic Editor: Sylvain Ouillon
Received: 5 December 2016 / Revised: 24 January 2017 / Accepted: 6 February 2017 / Published: 14 February 2017
(This article belongs to the Special Issue Sediment Transport in Coastal Waters)
Abstract
In June 2016, an unusual East Coast Low storm affected some 2000 km of the eastern seaboard of Australia bringing heavy rain, strong winds and powerful wave conditions. While wave heights offshore of Sydney were not exceptional, nearshore wave conditions were such that beaches experienced some of the worst erosion in 40 years. Hydrodynamic modelling of wave and current behaviour as well as contemporaneous sand transport shows the east to north-east storm wave direction to be the major determinant of erosion magnitude. This arises because of reduced energy attenuation across the continental shelf and the focussing of wave energy on coastal sections not equilibrated with such wave exposure under the prevailing south-easterly wave climate. Narrabeen–Collaroy, a well-known erosion hot spot on Sydney’s Northern Beaches, is shown to be particularly vulnerable to storms from this direction because the destructive erosion potential is amplified by the influence of the local embayment geometry. We demonstrate the magnified erosion response that occurs when there is bi-directionality between an extreme wave event and preceding modal conditions and the importance of considering wave direction in extreme value analyses. View Full-TextKeywords:
East Coast Low; nearshore processes; coastal erosion; coastal management; climate change; numerical modelling; Southeast Australia
▼
Figures
Figure 1
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
Share & Cite This Article
MDPI and ACS Style
Mortlock, T.R.; Goodwin, I.D.; McAneney, J.K.; Roche, K. The June 2016 Australian East Coast Low: Importance of Wave Direction for Coastal Erosion Assessment. Water 2017, 9, 121.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.