IMOS - ABOS Deepwater Arrays (DA) Sub-facility, East Australian deep water array, East Australian Current 4 Mooring (EAC4) Platform

The EAC4 deepwater mooring was deployed in April 2012 at (-27.21 S, 154.65 E) off the Queensland coast, near Brisbane, Australia. The mooring was recovered in August 2013 and the array decommissioned, and a newly configured array (with new moorings) was redeployed in May 2015.

Instrumentation on the mooring includes 75kHz Acoustic Doppler Current Profilers (Long Ranger ADCPs), Seabird SBE37SMPs, temperature loggers (Star Oddi, Starmon Mini) and discrete current meters (Aquadopp 6000).

The mooring will collect a time series of full-depth profiles of water velocity and discrete temperature and salinity measurements.

The array will consist of 9 current meter and property moorings extending eastward from the Queensland Coastal Node shelf mooring array near Brisbane to the deep ocean. The moorings will be at 500-600 m intervals across the Continental Slope and increasing to 800-1000 m in the deep ocean.

The East Australian Current (EAC) is the major western boundary current of the south Pacific Ocean. It plays a critical role in the ocean re-distribution of global heat from the equator to the midand- high latitudes. The EAC is relatively stable north of Brisbane, but as the current moves south 2-3 large eddies are pinched off every year. These eddies frequently move onto the continental shelf and close inshore and influence the local circulation patterns. At prominent coastal features the EAC moves away from the coast, driving upwelling which draws nutrient-rich water from a depth of 200-m or more.