Published works

The major hazard in coastal regions is inundation through extreme water levels generated in the ocean through different mechanisms such as storm surges and tsunamis or through a combination of effects such as a relatively small storm surge coinciding with high astronomical tides. With rising in sea level, given water levels will be exceeded more and more frequently as progressively less severe storm conditions are required to achieve that water level.

Therefore, it is critical that the exceedance probabilities of extreme water levels are accurately evaluated to inform flood and erosion risk-based management and for future planning. To address this concern, this study estimated present day extreme sea level exceedance probabilities due to storm surges, tides and mean sea level around the whole coastline of Australia through the application of a numerical model. 

The SCHISM hydrodynamic model, forced by TPXO tides and JRA55 atmospheric reanalysis (wind and air pressure), was successfully applied to produce a 59 year sealevel hindcast (1958-2016) for the entire Australian region. 

The outputs provide uninterrupted hourly sea level records at <1 km resolution around the Australian coast. Improvements compared to the previous Haigh et al. [2014b] dataset included: extending the hindcast by six years including several record storm surge events, higher spatial resolution, improved meteorological forcing, and 3-D hydrodynamic model implementation. Other physical processes, missing from earlier studies, were also examined in detail including: effects of surface gravity waves, continental shelf waves, and meteorological tsunamis.

Extreme value analysis has been applied to the sea level data to predict Average Recurrence Intervals (ARI) at ~1km spacing around the entire Australian coastline including islands. These statistics and relevant plots and time series data have been made available to the public via an interactive web tool (www.ozsealevelx.org), providing a consistent, accessible, up-to-date dataset for use by coastal planners and emergency managers.

This report provides an overview of the website and describes of how to access and interpret the available extreme sea level data.