The deep water Argo floats are being deployed by a research expedition that set sail last week for Antarctica in the CSIRO's research vessel Investigator. It will spend six weeks gathering information.
About 3800 Argo floats are already being used to collect information about ocean temperatures and salinity up to a depth of 2000 metres.
However, the new floats, which will be used by the expedition are data-collecting, autonomous ocean robots that can gather information up to depths of 5000 metres.
“The world’s climate is strongly influenced by the oceans, and the vast Southern Ocean plays a major role in how climate variability and change will play out in future decades,” he said.
Dr Steve Rintoul with the Investigator in the background.
“We already know that the Southern Ocean makes important contributions to global sea level change through taking up more heat than any other ocean on Earth and through influencing how fast the Antarctic Ice Sheet loses mass.
“To understand this system we need comprehensive and continuous measurements over a huge area of ocean, which has been very difficult in the past.”
Dr Rintoul’s team will use 11 deep-water floats near the Antarctic edge that have been supplied by the Scripps Research Institute, US; Japan Agency for Marine-Earth Science and Technology; and Laboratoire d’Océanographie et du Climat, France.
“It’s the first time these next-generation deep water Argo floats will be deployed near Antarctica. By providing year-round measurements through the full ocean depth, the floats will fill a massive data gap for the climate research community,” Dr Rintoul said.
Scientists will also measure trace elements like iron, using ultra-clean techniques to avoid contamination. Phytoplankton, like humans, need small amounts of iron to be healthy. The voyage will help identify what controls how much biological activity occurs in the Southern Ocean.
During the Investigator’s journey, an international team of scientists will carry out experiments to explore interaction between aerosols and clouds.
Bureau of Meteorology project leader Dr Alain Protat said the experiments would use aircraft, ship-based and satellite observations to collect detailed data on clouds and the interactions between incoming radiation, aerosol production, and then the formation of precipitation.
The Investigator is run by the Marine National Facility and is Australia’s only blue-water research vessel.
Photo: courtesy CSIRO