The oceans off south eastern Australia have a complex circulation structure, especially downstream (south) of the East Australian Current separation zone (~31oS). The separation zone and subsequent eddy field drives the water temperature variability along the coast and influences nutrient upwelling and subsequent algal blooms for over 40% of Australia’s population.

The EAC and its eddies are strongly implicated in heat transport along the NSW coast. Both warm core and cold core eddies are strongly linked to fisheries recruitment, local biodiversity and marine park location. The EAC’s eddy field is strongly connected with other regional seas and currents, including dynamics to the south off eastern Tasmania, to the east around Lord Howe Island via the Tasman Front, and the East Auckland Current.

The Tasman Sea has the world’s fastest increase in water temperature of any regional sea. Off Port Hacking, south of Sydney, is one of Australia’s longest hydrographic monitoring stations (~60 years) and off Bondi Beach we have the longest current records (the ORS, since 1990).

It is our goal to investigate the key EAC features while building on historical observations.

The principal goals of NSW IMOS are to investigate the East Australian Current (EAC) and its effects on ecological systems of the continental shelf as follows:

1. To investigate EAC variability;

  • To investigate EAC variability;
  • EAC inter-annual variability and coastal separation;
  • The role of the EAC in the climate of Aust & NZ;
  • Western boundary current fluxes and advection of heat;
  • Decadal variation (e.g. ENSO ) versus climate change;

2. Key continental shelf processes such as dynamics, slope water intrusions, and coastal boundary layer effects;

  • Coastal processes associated with the onshore encroachment of the EAC;
  • Coastal boundary layer effects associated with interaction of EAC and shelf morphology;
  • Shelf edge upwelling and onshore transport of nutrients;
  • Export across the shelf (southward and offshore);
  • Enhanced monitoring and prediction of the coastal wave climate;
  • Contribution to improved ocean current prediction;

3. Primary productivity, biological connectivity, and EAC interactions;

  • Along shore and across shelf transport and connectivity of marine populations;
  • Long term variability of planktonic communities and rocky reef biota variables, especially those associated with climate variability
  • Relationship of the EAC, its eddies and oceanographic conditions on fisheries, and movements by megafauna (AATAMS);
  • Coastal eddies, retention and biological productivity;
  • Investigations of anthropogenic noise;
  • Remote sensing, new sensors (e.g. satellite fluorescence), calibration.

Although not restricted to the above, the observational data will have significant input to research by the participating scientists and management agencies. Further goals are to assist and complement the long term 60 year Port Hacking 50 and 100m stations (CSIRO/DECC), and the 17 year ORS mooring (Sydney Water), and 7 waver rider moorings (Manly Hydraulics Laboratory), while investigating shelf processes that drive the biological response inshore and to facilitate the Passive Acoustic Mooring deployment off NSW.

With these scientific objectives in mind we have developed our vision around:

  • The ability to answer pertinent questions in the short term (2-5 yrs) whilst building long term data sets;
  • Investigations on small spatial and temporal scales through to large scale & climate benefits;
  • Multi-disciplinary research built on integrated applications of IMOS facilities;
  • The potential for individual researchers to answer more specialised questions with concentrated efforts;
  • While adding value to existing data sets.

Contact NSW IMOS

Node Leader
Assoc Prof Justin Seymour
University of Technology, Sydney

NSW Operator Representative
Mark Scognamiglio 
General Manager, SIMS

Sydney Institute of Marine Science 
Mosman, NSW Australia 
+61 02 9435 4600