6.1 Offshore and coastal engineering and the effects of climate change

Description

The project involved three main components:

The first component involved an assessment of the potential future changes to extreme still water levels, in particular storm surge magnitude and frequency, under different climate scenarios along the whole coastline of Western Australia. As a first step to considering future conditions, an assessment was made of the historic changes in extremes throughout the 20th century, to set projected future changes in an appropriate context.

The second component involved determining potential future changes in the surface wave climate around the coastline of Western Australia. Again, as a first step the present and historic wave climate and its variability was examined to provide context for future change because the order of magnitude of the present variability might be greater than the projected change.

The third component of the project considered the impact of these past and potential future changes in mean sea level, storm surges and waves on coastal stability. In particular, Yanchep Lagoon where the beach is defined as ‘perched’, was selected as the main study region.

Aims

• To determine how the coast on the southwest of Australia will respond to the combined action of waves, storm surges and mean sea level rise under climate change.
• To demonstrate the process and application of multi-scale modelling to understand the complex sediment dynamics on a perched beach.

Reports

Bosserelle, C. (2014). Morphodynamics and sand transport on perched beaches.

Bosserelle, C., Pattiaratchi, C. & Haigh, I. (2012) Inter-annual variability and longer-term changes in the wave climate of Western Australia between 1970 and 2009. Ocean Dynamics 62, 63–76. doi.org/10.1007/s10236-011-0487-3

Gallop, Shari & Bosserelle, Cyprien & Pattiaratchi, Charitha & Eliot, Ian. (2011). Hydrodynamic and morphological response of a perched beach during sea breeze activity. Journal of Coastal Research. SI64. 75-79.

Gallop, S.L., Bosserelle, C., Pattiaratchi, C.B., Eliot, I., (2011). Hydrodynamic and morphological response of a perched beach during sea breeze. Proceedings of the 11th International Coastal Symposium ICS 22 2009 Szczecin, Poland. Journal of Coastal Research, Special Issue 64, pp. 75–79.

Gallop, S. L., Bosserelle, C., Pattiaratchi, C., & Eliot, I., (2011). Rock topography causes spatial variation in the wave, current and beach response to sea breeze activity. Marine Geology, 290, 29–40. doi.org/10.1016/j.margeo.2011.10.002

Gallop, S.L., Verspecht, F. & Pattiaratchi, C.B. (2012) Sea breezes drive currents on the inner continental shelf off southwest Western Australia. Ocean Dynamics 62, 569–583. doi.org/10.1007/s10236-011-0515-3

Haigh, I.D., Eliot, M., Pattiaratchi, C., (2011). Global influences of the 18.61 year nodal cycle and 8.85 year cycle of lunar perigee on high tidal levels, J. Geophys. Res., 116, C06025, doi.org/10.1029/2010JC006645

Haigh, I. D., Wahl, T., Rohling, E. J., Price, R. M., Pattiaratchi, C., Calafat, F. M., & Dangendorf, S. (2014). Timescales for detecting a significant acceleration in sea level rise. Nature Communications, 5, 11pp. [4635]. doi.org/10.1038/ncomms4635

Haigh, I.D., MacPherson, L.R., Mason, M.S, Wijeratne E.M.S., Pattiaratchi C, Crompton R.P., George S (2014) Estimating present day extreme water level exceedance probabilities around the coastline of Australia: tropical cyclone-induced storm surges. Clim Dyn 42, 139–157. doi.org/10.1007/s00382-012-1653-0

Haigh, Ivan & Wijeratne, Ems & MacPherson, Leigh & Mason, Matthew & Pattiaratchi, Charitha & Crompton, Ryan & George, Steve. (2012). Estimating present day extreme total water level exceedance probabilities around the coastline of Australia. SESE report. 177. ISBN: 978-0-9871939-2-6