The East Australian Current (EAC) is the complex and highly energetic western boundary current of the South Pacific Ocean. The EAC is the dominant mechanism for the redistribution of heat and freshwater between the ocean and atmosphere in the Australian region; it is a vital component of the eastern Australian coastal ecosystem. The monitoring of the EAC is central to our understanding of how climate variability is communicated through the global ocean.
The IMOS Ocean Glider Facility (operated by The University of Western Australia) has recently deployed four Sea gliders north of the EAC deep water mooring line. The ocean gliders were deployed in early March and will stay in the water for approximately two and half months.
After their deployment the ocean gliders were navigated southwards until they intersected with the mooring array. Upon reaching the mooring line they then began their planned deployment of a continuous transect between the on-shore and off-shore extremities of the mooring array. The ocean gliders are undertaking full depth (0-1000m) profiles approximately every 12 hours, and are being actively piloted to achieve best success of keeping them on the designated transect.
The EAC ocean glider deployments will provide high resolution profiles, from 0-1000m, coincident with the EAC deep water mooring array. They will be used to understand the spatial structure of the EAC along the mooring line and help with the development of an efficient and cost effective observing system to monitor the EAC.
The data will also provide significant insights into the interactions between the EAC, the Pacific basin and the local shelf ocean circulation.
The monitoring of the EAC with the ocean gliders will more specifically:
- provide improved understanding of relationship of EAC to the South Pacific gyre;
- determine the impact of the EAC variability on the shelf circulation and coastal marine ecosystem;
- enable investigation of the relative influence of local and large-scale remotely driven variability on coastal dynamics and;
- build a long time-series of the EAC for assessment of the simulation of the EAC system in climate and ocean models including BlueLINK, ACCESS and eReef and other high resolution coastal models; and
- add to the international global ocean observing system for boundary current monitoring (e.g. Gulf Stream, Agulhas Current and Kuroshio Current).