NOAA Office for Coastal Management Coastal Inundation Digital Elevation Model: Virginia, Southern

These data were created as part of the National Oceanic and Atmospheric Administration Office for Coastal Management's efforts to create an online mapping viewer called the Sea Level Rise and Coastal Flooding Impacts Viewer. It depicts potential sea level rise and its associated impacts on the nation's coastal areas. The purpose of the mapping viewer is to provide coastal managers and scientists with a preliminary look at sea level rise and coastal flooding impacts. The viewer is a screening-level tool that uses nationally consistent data sets and analyses. Data and maps provided can be used at several scales to help gauge trends and prioritize actions for different scenarios. The Sea Level Rise and Coastal Flooding Impacts Viewer may be accessed at: https://coast.noaa.gov/slr.

This metadata record describes the Virginia, Southern digital elevation model (DEM), which is a part of a series of DEMs produced for the National Oceanic and Atmospheric Administration Office for Coastal Management's Sea Level Rise and Coastal Flooding Impacts Viewer described above. This DEM includes the best available lidar known to exist at the time of DEM creation that met project specifications. This DEM includes data for Chesapeake, Chesterfield, Colonial Heights, Franklin City, Hopewell, Isle of Wight, Norfolk, Petersburg, Portsmouth, Prince George, Richmond City, Southampton, Suffolk, Surry, and Virginia Beach Counties.

The DEM was produced from the following lidar data sets:

1. 2014 NGS Coastal Mapping Program Topobathy Lidar: Post-Sandy Atlantic Seaboard

2. 2013 USGS Norfolk, VA Lidar

3. 2014 Virginia Hurricane Sandy QL2 Lidar

4. 2011 FEMA Virginia Lidar

5. 2010 ARRA-VA 11County

The DEM is referenced vertically to the North American Vertical Datum of 1988 (NAVD88) with vertical units of meters and horizontally to the North American Datum of 1983 (NAD83). The resolution of the DEM is approximately 3 meters.

The NOAA Office for Coastal Management has developed high-resolution digital elevation models (DEMs) for use in the Office's Sea Level Rise and Coastal Flooding Impacts internet mapping application. These DEMs serve as source datasets used to derive data to visualize the impacts of inundation resulting from sea level rise along the coastal United States and its territories.

10987

Source data and their associated metadata are available at the following URLs:

1. 2014 NGS Coastal Mapping Program Topobathy Lidar: Post-Sandy Atlantic Seaboard

Metadata: https://coast.noaa.gov/htdata/lidar1_z/geoid12b/data/4800/2014_NGS_postSandy_topobathy_metadata.html

Data Download: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=4800

2. 2013 USGS Norfolk, VA Lidar

Metadata: http://viewer.nationalmap.gov/basic/

Data Download: http://viewer.nationalmap.gov/basic/

3. 2014 Virginia Hurricane Sandy QL2 Lidar

Metadata: http://viewer.nationalmap.gov/basic/

Data Download: http://viewer.nationalmap.gov/basic/

4. 2011 FEMA Virginia Lidar

Metadata: http://viewer.nationalmap.gov/basic/

Data Download: http://viewer.nationalmap.gov/basic/

5. 2010 ARRA-VA 11County

Metadata: http://viewer.nationalmap.gov/basic/

Data Download: http://viewer.nationalmap.gov/basic/

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Geographic:

Latitude_Resolution: 0.000027

Longitude_Resolution: 0.000027

Geographic_Coordinate_Units: Decimal degrees

Geodetic_Model:

Horizontal_Datum_Name: North American Datum of 1983

Ellipsoid_Name: Geodetic Reference System 80

Semi-major_Axis: 6378137.000000

Denominator_of_Flattening_Ratio: 298.257222101

Vertical_Coordinate_System_Definition:

Altitude_System_Definition:

Altitude_Datum_Name: North American Vertical Datum of 1988

Altitude_Resolution: 0.001

Altitude_Distance_Units: meters

Altitude_Encoding_Method: Explicit elevation coordinate included with horizontal coordinates

Any conclusions drawn from the analysis of this information are not the responsibility of the NOAA Office for Coastal Management or its partners.

None

The dataset is provided as is, without warranty to its performance, merchantable state, or fitness for any particular purpose. The entire risk associated with the results and performance of this dataset is assumed by the user. This dataset should be used strictly as a planning reference and not for navigation, permitting, or other legal purposes.

The DEM is derived from the source lidar data. Horizontal accuracy testing is not performed on the DEM. Lidar source data assumed to meet 1 meter horizontal accuracy.

The DEM is derived from the source lidar data. Vertical accuracy is not tested on the DEM. Project specifications require all source lidar data used in constructing the DEM to meet FEMA Specifications for Flood Hazard Mapping.

A visual qualitative check was performed to ensure data completeness. All available lidar data known at the time of DEM creation that meets project specifications has been used to develop the DEM. Known data gaps may exist where lidar coverage was incomplete.

Data covers the tile scheme provided for the project area. Elevation data checked for anomalous elevation values outside expected range.