Scientists will use sea robots to investigate deeper into the Southern Ocean than ever before in the pursuit of information about the climate.
A team of international researchers will set sail from Hobart on Thursday aboard the CSIRO research vessel Investigator to deploy 11 of the latest model deep-sea Argo floats near Antarctica.
The autonomous ocean robots will provide year-round data from depths of 5,000 metres – 3,000 metres deeper than they have previously gone in the Southern Ocean.
Chief scientist Steve Rintoul said it would be the first time scientists had a tool that could provide continuous measurements of the deep ocean.
“These are simple robots that will sit near the sea floor, every month they will rise to the surface measuring temperature and salinity and transmit that data back to us via satellite,” he said.
“This will be the first time that those kind of instruments are deployed near Antarctica.”
Dr Rintoul said data collected during the six-week voyage would provide critical information.
“The Southern Ocean is important because it is the pathway by which the ocean stores heat and carbon and that slows down climate change,” he said.
“When the ship returns we will have a much better feeling for how the Southern Ocean works, what it means for climate and what it means for the future of the Earth.”
Much still to learn from Southern Ocean
On Wednesday the Bureau of Meteorology (BOM) confirmed 2017 was Australia’s third-warmest year on record.
Dr Rintoul said the ocean was an important part of the climate system.
“As the Earth has warmed over the last 50 years, more than 93 per cent of the extra heat that has been stored by the planet has been stored in the oceans,” Dr Rintoul said.
“Seven of the warmest years on record have happened in the last 10 years.
“What our voyage will do is show how the Southern Ocean is responding to these changes in climate, but also how the Southern Ocean will in turn feed back on climate and drive further change in the future.”
During the Investigator’s journey, an international team of scientists from agencies including the CSIRO, the Australian Bureau of Meteorology, the US National Centre for Atmospheric Research, and the University of Utah, will also conduct experiments to explore the interaction between aerosols and clouds.
Bureau of Meteorology project leader Alain Protat said that the experiments would use a combination of aircraft, ship-based and satellite observations to collect data on clouds and the interactions between incoming radiation, aerosol production, and the formation of precipitation.
“The Southern Ocean region is the cloudiest place on Earth, yet we don’t understand why these clouds are different from clouds in other regions,” Dr Protat said.
“The lack of pollution over this remote region is a possible explanation, which we will explore with these unprecedented observations.”
He said researchers know from reference satellite observations that global climate models struggle to represent the energy balance at the Earth’s surface over the Southern Ocean region.
What that means for the accuracy of future climate predictions is largely unknown.
“The complexity of the problem requires collocated, state-of-the art measurements of aerosol, clouds, precipitation and radiation to understand the interactions and feedbacks between them,” Dr Protat said.