TAKING THE PULSE OF THE SOUTHERN OCEAN
$2M Grant to GSO For Ocean Climate Research
on the Antarctic Circumpolar Current that flows from west to east in the Southern Ocean at about 50° south latitude, unimpeded by any land masses. The current is driven by strong westerly winds infamously known to mariners as the "Roaring Forties," the "Furious Fifties," and the "Screaming Sixties."
on the Antarctic Circumpolar Current that flows from west to east in the Southern Ocean at about 50° south latitude, unimpeded by any land masses. The current is driven by strong westerly winds infamously known to mariners as the "Roaring Forties," the "Furious Fifties," and the "Screaming Sixties." The region has experienced increased winds and warming in the last 30 years, making it a critical place to study climate change. Two GSO oceanographers, Drs. Kathleen Donohue and Randy Watts, aim to do just that.
They were awarded a five-year, $2-million grant by the National Science Foundation to measure this current that flows around Antarctica. “The Antarctic Circumpolar Current acts as a conduit transporting water among Atlantic, Pacific, and Indian Oceans. The nature of this flow has consequences for local, regional, and global ecosystems and climate,” explained the project leader, Kathleen Donohue, GSO Assistant Professor. “It’s important to understand the dynamics of the Current so we can understand the impacts of our changing climate.”
The transport rate of the current is a key measurement used to validate the accuracy of many numerical models used in oceanography because the Current is the pulse of the Southern Ocean. The Drake Passage located between Antarctica and the tip of South America is the Current’s narrowest passage, a choke point that is an ideal location for this experiment.
In November 2007, Donohue, along with GSO Professor Randy Watts and Dr. Teresa Chereskin of the Scripps Institution of Oceanography will deploy 35 current and pressure recording inverted echo sounders across the Drake Passage. Inverted echo sounders, a new technology pioneered by Watts, have been used to monitor 
oceanic fronts since the 1970s. Since then, inverted echo sounders have been deployed around the world to study major oceanic fronts and currents. The instruments will be left in place, undisturbed, for 4 years.
oceanic fronts since the 1970s. Since then, inverted echo sounders have been deployed around the world to study major oceanic fronts and currents. The instruments will be left in place, undisturbed, for 4 years. The team will make annual visits to the region aboard U.S. Antarctic Program research vessels to gather the data collected by the devices. Dr. Donohue expects that these observations will help us understand why the current is there, what forces it, and what controls its variability. The Antarctic Circumpolar Current may be highly sensitive to climate change since it is driven by winds, and the winds appear to be changing as a result of global climate change.
The research project will also result in recommendations for strategies for long-term monitoring of the current.
