Chemical, physical, profile and underway oceanographic data were collected aboard the GORDON GUNTER in the Gulf of Mexico from 2010-05-27 to 2010-06-04 in response to the Deepwater Horizon Oil Spill event on April 20, 2010, by the Subsurface Monitoring Unit (SMU), which consisted of multiple government and corporate agencies. These data include CDOM fluorescence, conductivity, current speed - east/west component (U), current speed - north/south component (V), dissolved oxygen, hydrostatic pressure, salinity, sound velocity, temperature and water density. The instruments used to collect these data included ADCP, CTD, bathythermograph - XBT, fluorometer and oxygen meter along with other physical sampling devices. More specific information about each data set is located in their individual metadata records. The Acoustic Doppler Current Profiler ADCP used sonar to measure and record water current velocities and the distribution of suspended material over a range of depths. Absolute U- and V-component ocean current vectors from the ADCP collected can be used to create detailed maps of the distribution of water currents and suspended materials through the water column along the ship's path. The data from this ADCP is raw and unprocessed. Some of the datasets associated with this instrument are still incomplete and will be published as they become available. This data set also contains products created for use in real time analysis and decision support. These products may include charts, graphs, maps, plots, and GIS formatted data files. The CTD data underwent preliminary quality assurance and control procedures at the National Coastal Data Development Center (NCDDC). Cruise level information consisting of data management documents, cruise reports and plans, videos and pictures, and other miscellaneous documentation were gathered by the data managers. (NODC Accession 0069067)