Using inflatable boats, a portable depth sounder with GPS, and a REMUS autonomous underwater vehicle, a team of scientists and engineers have created the first detailed chart of the ocean floor around Palmer Station in Antarctica, revealing previously unknown submerged rocks. The new chart, the first in 50 years, was made by a research team from the Woods Hole Oceanographic Institution (WHOI) and the University of Southern Mississippi over five weeks in April and early May as they looked for sites for a new underwater observatory. Their findings revealed a number of previously unmapped submerged rocks, among them a set of sharp rocky pinnacles that are potential navigational hazards. Some rise nearly 100 meters (about 330 feet) to a depth of six meters (about 20 feet) below the surface and near to the routes generally taken by ships through the area.
The previous nautical chart of the area was produced in the mid 1900’s by single soundings taken at very wide spacing. Although some underwater hazards were marked on the earlier chart, the old chart was found to be incorrect by at least 0.5 nautical miles (just under one mile). Since Palmer Station was first established as a scientific outpost in 1965, ships have followed a particular route through the visible rocks. In typical marine navigation in poorly charted waters, ships new to the area proceed cautiously, making continuous soundings with their bridge fathometer. They then note their routes on charts and follow the same routes when entering and departing the area.
Palmer Station is at 64°46’ S, 64°03’ W, on protected Arthur Harbor on the southwestern coast of Anvers Island, about midway down the Antarctica Peninsula. Palmer is one of three U.S. research stations on the continent and the only station north of the Antarctic Circle. Named for American sealer Nathaniel B. Palmer, who in 1820 was one of the first to see Antarctica, the station was built in 1968 to replace the prefabricated wood huts of ’Old Palmer’ station, established in 1965. In 1990 Palmer Station was designated by the National Science Foundation as a long term ecological research (LTER) site.