This data set was acquired with a ship-based Kongsberg EM120 Multibeam Sonar system during Nathaniel B. Palmer expedition NBP1101 conducted in 2011 (Chief Scientist: Dr. Josh Kohut). These data files are of MBSystem Compatible format and include Swath Bathymetry, Acoustic Backscatter, and Sidescan data that have not been processed. Data were acquired as part of the project(s): Ross Sea Expedition, and funding was provided by NSF grant(s): ANT08-39039.