Integrated Land Change Monitoring

Accurate, high-resolution elevation information is vital to understanding the highly dynamic northern Gulf of Mexico coast, the location of North America’s largest delta system and the focus of one of the largest coastal restoration and flood risk reduction efforts in the United States. The northern Gulf of Mexico topobathymetric digital elevation model (TBDEM) was developed in collaboration...

With an estimated elevation of only 3-meters above sea level, the Majuro Atoll, capital of the Republic of the Marshall Islands (RMI), is extremely vulnerable to sea-level rise, tsunamis, storm surge, and coastal flooding that could impact the sustainability of the infrastructure, groundwater, and ecosystems. Located in the northern tropical Pacific Ocean, the waters surrounding the Majuro Atoll...

Mobile Bay is ecologically important as it is the fourth largest estuary in the United States. The Mobile Bay topobathymetric digital elevation model (TBDEM) was developed in collaboration between U.S. Geological Survey (USGS) Coastal and Marine Geology Program (CMGP) and USGS National Geospatial Program (NGP) using a combination of 71 disparate topographic and bathymetric datasets collected from...

Hurricane Sandy severely impacted the New Jersey/Delaware coast, altering the topography and ecosystems of this heavily populated region. In response to the storm, the U.S. Geological Survey (USGS) Coastal and Marine Geology Program in collaboration with USGS National Geospatial Program , and National Oceanic and Atmospheric Administration developed three-dimensional (3D) topobathymetric elevation...

Coastal shoreline mapping is a particularly complex issue because of the dynamic nature of water levels at the land-water interface, the various tidal vertical datums in use, and the spatial scale of the shoreline delineation. In addition, the definition of a shoreline varies depending on whether the shoreline will be used for nautical charts and navigation, delineating the legal federal and state...

Most airborne topographic light detection and ranging (lidar) systems operate within the near-infrared spectrum. Laser pulses from these systems frequently are absorbed by water and do not generate reflected returns on water bodies in the resulting lidar point cloud. Thus, the absence of lidar returns over water is useful for identifying inland water bodies that are not connected by any path to...

Hydrologic connectivity of light detection and ranging (lidar)-derived elevation data is critical for coastal hydrologic modeling applications. However, unless hydrologically-enforced, raised structures (i.e. bridges, roads overlaying culverts) can block overland flow to coastal waters. Because highly detailed lidar-derived elevation surfaces include features such as bridge decks and road fill...

Coastal topographic and bathymetric (topobathymetric) data with high spatial resolution (1-meter or better) and high vertical accuracy are needed to assess the vulnerability of Pacific Islands to climate change impacts, including sea-level rise. According to the Intergovernmental Panel on Climate Change reports, low-lying atolls in the Pacific Ocean are extremely vulnerable to king tide events...

The USGS Coastal National Elevation Database Applications Project organized a workshop in cooperation with the College of Staten Island-City University of New York to discuss storm surge modeling and get input from scientists across a broad community. The workshop, held on April 22-23, 2014 on the College of Staten Island campus, is part of a larger project intended to enhance topobathymetric...

The Coastal National Elevation Database Applications Project supports scientific research and applications assessing restoration, redevelopment, and protection projects in the Hurricane Sandy impact areas along New Jersey and New York coastal beaches.

Scientific research and applications assessing coastal landscape change and vulnerability are critical for applications such as shoreline mapping, hydrodynamic modeling, coastal vulnerability, and coastal geomorphology studies. However, very little ground truth data are available within the intertidal zone and adjacent beaches.

Defining near-shore water depth (bathymetry) is problematic because ships cannot operate close to the shore while collecting acoustic bathymetric soundings. Alternatively, optical green laser lidar sensors have been used to collect bathymetric points, however, these types of lidar acquisitions are costly for the footprint collected and are subject to bathymetric inaccuracies in turbid water...