Vegetation and Building Heights for Accomack and Northampton Counties, Virginia, April 2015

This dataset gives the aboveground height of vegetation and buildings in Northampton and Accomack Counties, VA in April 2015. LiDAR data were collected April 11-24, 2015. A mosaiced DEM of ground elevations was assembled from DEM tiles from USGS. A LAS dataset of the classified LiDAR point cloud was assembled and a DEM of first-returns (representing the top of vegetation of buildings) created. The ground-elevation DEM was subtracted from the first-return DEM to yeild a difference layer that reflects the height of the vegetation or buildings above the ground level. Areas classified as Ponds, Lakes or Tidal areas were all set to 0 to avoid artifacts caused by waves etc. The resulting DEM was reprojected from State Plane to UTM coordinates and elevation units were changed from US Feet to Meters. The data contains some odd values in the seaside portion of the data. Heights > 10 meters in marsh areas are highly suspect.