23 Jan Australian Coastal Ocean Radar Network

Australian Coastal Ocean Radar Network

(ACORN)

Did you ever wonder what the rusty old locked container on the northern dunes above The Groyne at Guilderton was used for?

It is an ACORN (Australian Coastal Ocean Radar Network) station which uses land based high frequency radar to provide continuous mapping of sea-surface currents at six locations around the Australian coast, each location comprising two stations. This station is measuring sea surface currents over an area of approximately 150km by 150km of the Indian Ocean including Rottnest Island, where the second station is situated and the Perth Canyon. The Perth Canyon has the highest marine biodiversity in the region, with whale and fish aggregations, and high primary and secondary productions which are controlled by the physical oceanographic processes. Combined with the dynamics of the Perth Canyon is the dominant Leeuwin Current which produces a wake on the leeward side of Rottnest Island. This is a topographically induced up-welling. The region is influenced by Swan River outflow, submarine groundwater discharges, and waste-water outfalls.

Data is transmitted to James Cook University in Townsville for processing and forwarding to the IMOS (Integrated Marine Observing System) data portal, where it can be assessed by researchers and the public.
The radar systems monitor the seasonal, inter-annual and decadal variability of the Leeuwin Current and its eddy fields. The Leeuwin Current system and its climate variability has crucial impacts on most of the local marine based industries, such as commercial and recreational fishing, defence, marine tourism and recreation, petroleum exploration and production, ship building, ports and shipping. It was also used in the disappearance of the missing Malaysian Airlines flight MH370.

You can home in on the ocean area off Fremantle/Guilderton and get the details on the following link:

IMOS – Rottnest Island HF Ocean Radar Site
imos.aodn.org.au

Bob Johnson