Tagged seals plumb Southern Ocean’s depths
Seals diving for their dinner near Antarctica have surfaced with an extra morsel: information, gathered by electronic tags on the animals’ heads, about the shape of the seafloor there.
The work has revealed previously unknown undersea channels, through which warm water might flow toward fragile ice shelves. And the seals do it all for a fraction of the cost of traditional seafloor mapping done from ships.
“It gives you a much denser picture of what the water depth is than anything you can conceivably do with ship tracks,” says Laurence Padman, an oceanographer at Earth & Space Research in Corvallis, Ore., and a coauthor of an upcoming paper in G