ClimateWire: When British Capt. James Cook undertook his second voyage in the Southern Ocean in 1772, scientists on board measured the temperature 183 meters below the surface. It was colder than at the surface.
Scientists have since graduated to vastly improved technologies for measuring the ocean's temperatures. By 2004, they had launched Argo ("swift" in Greek), a network of 3,000 floating devices spread out throughout the world. The devices record the temperatures down to 6,500 feet, where only the deepest...