The Windows to the Deep 2021: Southeast U.S. ROV and Mapping expedition (EX-21-07) was a combined mapping and remotely operated vehicle (ROV) expedition to the Blake Plateau and Florida Straits that took place between October 26 and November 15, 2021. Operations during this 21-days at sea expedition included a combination of ROV dives in support of NOAA Ocean Exploration and its partner priorities. The primary focus of this expedition was the Blake Plateau, including its escarpment, off the coast of the Southeast U.S., but three dives were also conducted in the western and central Florida Straits due to weather conditions. Overall, 14 dives were completed, including two explorations of the water column, several dives to mound and ridgelike structures likely to be bioherms, two deeper dives to explore the steep Blake Escarpment, and one dive to document a lone sinkhole in the southeast region of the Blake Plateau. ROV dives were conducted from 300 m to 3650 meters water depth for a total of 47 hours of bottom time, and 15,800 square km were mapped using EM 304 multibeam sonar. All data associated with this expedition have been archived and are publicly available through the NOAA Archives.

The National Oceanic and Atmospheric Administration (NOAA) has the statutory mandate to collect hydrographic data in support of nautical chart compilation for safe navigation and to provide background data for engineers, scientific, and other commercial and industrial activities. Hydrographic survey data primarily consist of water depths, but may also include features (e.g. rocks, wrecks), navigation aids, shoreline identification, and bottom type information. NOAA is responsible for archiving and distributing the source data as described in this metadata record.

The National Oceanic and Atmospheric Administration (NOAA) has the statutory mandate to collect hydrographic data in support of nautical chart compilation for safe navigation and to provide background data for engineers, scientific, and other commercial and industrial activities. Hydrographic survey data primarily consist of water depths, but may also include features (e.g. rocks, wrecks), navigation aids, shoreline identification, and bottom type information. NOAA is responsible for archiving and distributing the source data as described in this metadata record.

The National Oceanic and Atmospheric Administration (NOAA) has the statutory mandate to collect hydrographic data in support of nautical chart compilation for safe navigation and to provide background data for engineers, scientific, and other commercial and industrial activities. Hydrographic survey data primarily consist of water depths, but may also include features (e.g. rocks, wrecks), navigation aids, shoreline identification, and bottom type information. NOAA is responsible for archiving and distributing the source data as described in this metadata record.

The National Oceanic and Atmospheric Administration (NOAA) has the statutory mandate to collect hydrographic data in support of nautical chart compilation for safe navigation and to provide background data for engineers, scientific, and other commercial and industrial activities. Hydrographic survey data primarily consist of water depths, but may also include features (e.g. rocks, wrecks), navigation aids, shoreline identification, and bottom type information. NOAA is responsible for archiving and distributing the source data as described in this metadata record.

The National Oceanic and Atmospheric Administration (NOAA) has the statutory mandate to collect hydrographic data in support of nautical chart compilation for safe navigation and to provide background data for engineers, scientific, and other commercial and industrial activities. Hydrographic survey data primarily consist of water depths, but may also include features (e.g. rocks, wrecks), navigation aids, shoreline identification, and bottom type information. NOAA is responsible for archiving and distributing the source data as described in this metadata record.

Between April 14 and May 10, 2021 EX-21-01 performed the sea acceptance testing of the newly installed Kongsberg EM 304 MKII transmit array, conducted mission readiness of the mapping systems through annual testing and calibration, and mapped unexplored areas of the Blake Plateau. In addition to the EM 304 multibeam sonar objectives, EK60/80 split-beam echosounder objectives included acceptance of the newly installed EK80 38 kHz transducer and calibration of each frequency (18, 38, 70, 120, 200 kHz). Other mission readiness objectives included ensuring functionality of all ancillary equipment, including sound speed profiling equipment, updating and refining procedural documents, and defining new procedures for supporting shore-based processing using the Cloud. EX-21-01 collected 22,187 square kilometers of bathymetry and associated water column data, with 18,773 square kilometers being within the U.S. Exclusive Economic Zone and Territorial Sea deeper than 200 m.

The National Oceanic and Atmospheric Administration (NOAA) has the statutory mandate to collect hydrographic data in support of nautical chart compilation for safe navigation and to provide background data for engineers, scientific, and other commercial and industrial activities. Hydrographic survey data primarily consist of water depths, but may also include features (e.g. rocks, wrecks), navigation aids, shoreline identification, and bottom type information. NOAA is responsible for archiving and distributing the source data as described in this metadata record.

The National Oceanic and Atmospheric Administration (NOAA) has the statutory mandate to collect hydrographic data in support of nautical chart compilation for safe navigation and to provide background data for engineers, scientific, and other commercial and industrial activities. Hydrographic survey data primarily consist of water depths, but may also include features (e.g. rocks, wrecks), navigation aids, shoreline identification, and bottom type information. NOAA is responsible for archiving and distributing the source data as described in this metadata record.

The National Oceanic and Atmospheric Administration (NOAA) has the statutory mandate to collect hydrographic data in support of nautical chart compilation for safe navigation and to provide background data for engineers, scientific, and other commercial and industrial activities. Hydrographic survey data primarily consist of water depths, but may also include features (e.g. rocks, wrecks), navigation aids, shoreline identification, and bottom type information. NOAA is responsible for archiving and distributing the source data as described in this metadata record.