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Eastern Geographic Science Center

Description of Current Projects

Coastal National Elevation Database Applications Project (CoNED)

Investigator: Monica Palaseanu-Lovejoy, U.S. Geological Survey, Eastern Geographic Science Center

Automatic extraction of cliff tops and toes and generation of orthogonal transects and profiles using aerial lidar derived DEMs and
terrestrial lidar point clouds, southern California.
The Science Issue and Relevance
Airborne and terrestrial lidar-based high-resolution bare earth Digital Elevation Models (DEMs) are important in measuring coastal erosion, assessing vulnerability to pending climate change impacts such as sea level rise and extreme storm events, and modeling and monitoring features such as beaches, sea cliffs, levees, and dunes.

Methodology for Addressing the Issue
The Coastal National Elevation Database (CoNED) Applications Project ( team uses airborne and terrestrial lidar data for analysis, mapping and research. Recently, results from structure-from-motion (SfM) techniques were added to the resources used. Terrestrial lidar surveys are deployed to map vertical features such as sea cliffs, levees and dunes at higher resolutions and accuracies than airborne lidar can deliver. SfM is employed as a cheaper alternative to terrestrial lidar in areas with sparse vegetation or with restricted access. Eastern Geographic Science Center staff support the CoNED project by:
  • conducting terrestrial lidar surveys, processing lidar point clouds, and developing new automatic techniques to derive products such as the extraction of cliff tops and bases, generation of orthogonal transects and profiles, and analysis
    of cliff face geometry. Similar analyses were done on surveyed levees in southern Louisiana and San Francisco Bay, California;

  • cliff morphology change analysis in southern California, and automatic extraction of basic metrics of bluff morphology in the northern slope of Alaska; and

  • researching new techniques such as SfM, processing SfM data and generating dense georeferenced point clouds, and image ortho-mosaics.

A. Photo of structure on He'eia fish pond wall,
B. Airborne lidar point cloud, 2013: higher positional accuracy.
C. SfM point

Future Steps
Upcoming work on the CoNED project includes validation of automatic extraction of cliff morphology metrics, developing methods to compute metrics of wetland fragmentation on large areas, and using lower-cost alternatives to airborne lidar for example, SfM data aquired from different platforms such as kites, balloons and unmanned aerial systems.

Key Words: Airborne lidar, terrestrial lidar, digital elevation models, structure-from-motion, point clouds

Contact Information:
Monica Palaseanu-Lovejoy, PhD

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