Extreme Water Levels for Australian Beaches using Empirical Equations for Shoreline Wave Setup

This data is associated with the paper O’Grady, J.G., McInnes, K.L., Hemer, M. A., Hoeke, R. K., Stephenson, A., and Colberg, F. (in press), "Extreme Water Levels for Australian Beaches using Empirical Equations for Shoreline Wave Setup", Journal of Geophysical Research: Oceans.\n\nUnderstanding how high ocean water levels can reach up the coast is important for designing coastal protection from coastal inundation and erosion. This is particularly important as climate change affects wind and weather conditions and sea-level rise with the subsequent modification to the occurrence of the largest storm-driven water levels. While the height of storm-driven water levels are well understood for protected harbours and estuaries, new research is providing estimates of how high water levels can reach for coastlines exposed to dangerous wave/surf conditions. This study uses mathematical model simulations spanning ~30 years of historical water levels and ocean waves. Statistical analysis is performed to determine how high the largest storm events will likely reach on natural sandy beaches directly exposed to large wave/surf conditions. \n\nThe data comprises Gumbel distribution parameters from regression fitting to the hindcast model data.\nThe file ST_rGUM_25m_sta.1981-2013.nc is for the storm-tide SWL heights from the ROMS storm surge hindcast. \nThe file SU_GT81_rGUM_25m_sta.1981-2013.nc is for wave setup calculated with the Guza, R. T., & Thornton 1981 method. \nThe file SU_GT81_ST_rGUM_25m_sta.1981-2013.nc is for the time-series combined storm-tide and wave setup. \nNotes:\n1) The data datum is relative to the model bathymetry mean sea level (Geoscience Australia’s 2009 250m dataset). Haigh corrected their dataset of storm tide to AHD by comparing modelled 1-year ARI to the tide gauge measurements. “The predicted levels have been artificially adjusted so that the 1-year return period levels exactly match those of the measured estimates at each site. This was done because the predicted water levels are relative to MSL, whereas the measured levels are relative to AHD. Around mainland Australia, AHD was defined using MSL records between 1966 and 1968 at 30 sites and hence differs from present day MSL. Around Tasmania, AHD was defined using two records from 1972.”\n2) To convert to AHD, the netcdf file ‘ST_rGUM_25m_sta.1981-2013.nc’ has a variable ‘toAHD’, you will need to add this onto the location parameter ‘mu’. Alternatively add it to the predicted return levels.\n3) Wave setup is really only valid for open coastlines exposed to waves, so be careful applying it in estuaries.\nLineage: Created with R's ismev Gumbel function on selected datasets (ROMS storm surge hindcast, CAWCR wave hindcast, and combined data).