Seafloor Elevation Change from the 1930s to 2016 Along the Florida Reef Tract, USA

The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify bathymetric changes along the Florida Reef Tract (FRT) from Miami to Key West within a 982.4 square-kilometer area. USGS staff calculated changes in seafloor elevation from the 1930s to 2016 using digitized historical hydrographic surveys (H-sheets) acquired by the U.S. Coast and Geodetic Survey (USCGS) in the 1930s and light detection and ranging (lidar)-derived digital elevation models (DEMs) acquired by the National Oceanic and Atmospheric Administration (NOAA) in 2016 and 2017. Most of the elevation data from the 2016/2017 time period were collected during 2016, so as an abbreviated naming convention, we refer to this time frame as 2016. An elevation change analysis between the 1930s and 2016 data was performed to quantify and map impacts to seafloor elevation and to determine elevation and volume change statistics for 14 habitat types found within the study area along the FRT. Data were collected under Florida Keys National Marine Sanctuary permit FKNMS-2016-068.