2018 FEMA Lidar DEM: Region 9, CA ca2018_region9_dem_m10258 eng Dataset EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION > DIGITAL ELEVATION/TERRAIN MODEL (DEM) EARTH SCIENCE > OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > BATHYMETRY > COASTAL BATHYMETRY EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION elevation CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > CALIFORNIA VERTICAL LOCATION > LAND SURFACE VERTICAL LOCATION > SEA FLOOR LIDAR > Light Detection and Ranging Airplane > Airplane Product: 3-foot bare-earth raster digital elevation model (DEM) data tiles in 32-bit floating point ERDAS IMG format. Geographic Extent: Approximately 10,547 square miles across 6 AOIs in California. Dataset Description: The CA-AZ FEMA R9 Lidar lidar project called for the planning, acquisition, processing, and production of derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.7 meters. Project specifications were based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 1.2. The data was developed based on a horizontal datum/projection of NAD83 (2011) State Plane California I & IV (FIPS Zone 0401 & 0404), US Survey Feet, and a vertical datum of NAVD88 (GEOID12B), US Survey Feet. Lidar data was delivered as processed LAS 1.4 files formatted to 10,516 individual 4,500-feet x 4,500-feet tiles. Ground Conditions: Lidar was collected in 2018 while no snow was on the ground and rivers were at or below normal levels. Due to a time difference of approximately one month between adjacent flight lines, there are two instances, a reservoir and a river bed, that show elevation drop-offs. Initial acquisition occurred when these features were dry, with the features containing water at the time of the follow-up flights. The feature portions that contain water were digitized, hydro-flattened, and incorporated into the DEM. In order to post process the lidar data to meet task order specifications and meet ASPRS vertical accuracy guidelines, Woolpert established 148 ground control points across all California AOIs that were used to calibrate the lidar to known ground locations established throughout the project area. An additional 258 independent accuracy checkpoints (145 NVA points and 113 VVA points), were collected across all California AOIs and used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data. This metadata record supports the data entry in the NOAA Digital Coast Data Access Viewer (DAV). For this data set, the DAV is leveraging the GeoTIFF files hosted by USGS on Amazon Web Services. OCM Partners OCM Partners https://www.fisheries.noaa.gov/inport/item/74843 https://www.fisheries.noaa.gov/inport/item/49404 https://www.fisheries.noaa.gov/inport/item/64466 northlimit=41.6482; eastlimit=-120.19359; southlimit=34.9635; westlimit=-123.00562; start=2018-01-22; end=2018-04-21; None 2019-03-14