AUSTRALIAN researchers have discovered that vast, pancake-shaped bodies of cool water, about 40 kilometres in diameter, are spinning out of Bass Strait into the Tasman Sea, and then turning east to head for the Indian Ocean.
The phenomenon happens at a stately pace, with perhaps one giant disc of water each year making it as far as the southern coast of Western Australia, after a journey of several years.
”At first we thought maybe there was a malfunction in the instruments,” said Mark Baird, an oceanographer and senior research fellow at the University of Technology, Sydney.
Advertisement: Story continues below”But there was no malfunction, we had just run into a ‘wall’ or water that was relatively sharp, and undiluted by the water around it. We were able to establish that it was a disc shape, a few hundred metres high and about 40 kilometres across.”
Dr Baird and fellow researcher Ken Ridgway from the CSIRO, were analysing data from a deep-diving ocean glider, a torpedo-like machine that dives a kilometre under the sea and then rises back to the surface, measuring water temperature and salinity.
Dozens of the gliders are deployed in the oceans of Australia’s coast and further afield, building up a detailed picture of ocean currents.