Multi-decadal Ocean Change
One of the key research areas of the NSW-IMOS Node is to contribute to national observations of decadal changes and climate variability of the East Australian Current (EAC), Leeuwin Current and Flinders Current using common platforms and metrics.
The East Australian Current (EAC) is the major western boundary current of the South Pacific Gyre, flowing from the southern Coral Sea and along the northern NSW coast (Ridgway & Dunn 2003). The EAC is Australia’s largest current and is typically 30 km wide, 200 m deep and travelling up to 4 knots.
The core of the EAC is centred over the continental slope, although its coastal presence is felt by eddy encroachment. Southeast Australian waters have experienced a multi-decadal warming over recent decades at a rate of between three and four times the global average (Holbrook and Bindoff 1997; Ridgway 2007). The strengthening of the EAC is predicted to further warm Australian waters by 1-2ºC by 2030 and 2-3 ºC by 2070s, particularly off Tasmania (Poloczanska et al. 2008). Consequently, the southeast Australian region is a global hot-spot for ocean temperature change.
Key Science Questions
- To determine the variability in EAC strength from its source in the Coral Sea, the seasonal and spatial variability in the separation of the EAC from central NSW, and the EAC’s southward extension.
- Contribute to monitoring the Bass Strait outflow and the northward coastally trapped wave propagation.
- Contribute to the national backbone through the National Reference Station network and the supplementation of Satellite Remote Sensing products with local data.