CSIRO02: Analysing long tide gauge records in Australia in conjunction with the 20th Century reanalysis to better understand how extreme events and by association extreme sea level events are changing

Understanding historical changes in extreme sea levels is necessary for the accurate projection of their changes over the next century. This project will look at digitized sea level data, to better understand the causes of extreme sea levels the southern Australian region and how these events vary over the duration of the record.

Supervisors: Prof Lisa Alexander (l.alexander@unsw.edu.au), Dr Kathleen MCInnes (kathleen.mcinnes@csiro.au)

Understanding historical changes in extreme sea levels is necessary for the accurate projection of their changes over the next century. High winds and falling atmospheric pressure associated with storm systems in coastal proximity can cause storm surges; i.e. sea levels that are elevated beyond those expected due to astronomical tides alone. Such episodes can produce significant detrimental coastal impacts such as flooding and erosion. In addition to storm surges, sea levels can also vary as a result of seasonal factors and climate variability due to phenomena such as El Nino Southern Oscillation, which also influence the severity and impact of storm surge events.

This project is for a graduate student to work with recently digitized sea level data for Williamstown, Melbourne that extends back to 1875 and potentially also the Fremantle (Perth) record that commences in 1880 and Fort Denison (Sydney) tide gauge records that commences in 1912. The goal is to use the tide gauge records in conjunction with the Twentieth Century Reanalysis (Compo et al, 2011) to better understand the causes of extreme sea levels the southern Australian region and how these events vary over the duration of the record.