64533 Data Set Published / External 59025 NGS Lidar Project Completed 2021 The NOAA Chesapeake Bay VA1901 Option 3 West 1 Topobathymetric lidar data were collected by NV5 Geospatial, Inc. (NV5) using a Riegl VQ-880-GH system. The Chesapeake Bay VA1901 Option 3 West 1 acquisition spanned from 20190217-20190412 in 15 missions. The Chesapeake Bay VA1901 Option 3 West 1 dataset includes Topobathymetric data in LAS format 1.4, point data record format 6, with the following classifications in accordance with project specifications and the American Society for Photogrammetry and Remote Sensing (ASPRS) classification standards: 1 - unclassified 2 - ground 7 - noise 40 - bathymetric bottom or submerged topography 43 - submerged feature 45 - water column 46 - overlap bathymetric bottom 71 - adjacent lift unclassified 72 - adjacent lift ground 85 - adjacent lift water column 1 Overlap - edge clip This data set also includes lidar intensity values, number of returns, return number, time, and scan angle. The 100 meter buffered NOAA Chesapeake Bay VA1901 Option 3 West 1 project area covers approximately 964.624 square kilometers of an area encompassing a portion of the Chesapeake Bay and the nearby census designated places of Diggs, Matthews, Onemo, Susan, New Point, Seaford, Grafton, and Poquoson, Virginia. LAS files were compiled in 500 m x 500 m tiles. The NOAA Chesapeake Bay VA1901 Option 3 West 1 dataset is comprised of 4,821 - 500 m x 500 m LAS tiles. This lidar data was required by National Oceanic and Atmospheric Administration (NOAA) and the National Geodetic Survey (NGS), Remote Sensing Division Coastal Mapping Program (CMP) to enable accurate and consistent measurement of the national shoreline. The CMP works to provide a regularly updated and consistent national shoreline to define America's marine territorial limits and manage coastal resources. The NOAA Chesapeake Bay VA1901 Option 3 West 1 data includes all lidar returns. An automated grounding classification algorithm was used to determine bare earth and submerged topography point classification. The automated grounding was followed with manual editing. Depth values were adjusted per sensor to NOAA provided ground truth data. Classes 2 (ground), 40 (submerged topography), and 43 (submerged feature) were used to create the final DEMs. It should be noted that topographic data gaps totaling 0.29 square kilometers are present within this dataset and have been delineated as “Data Void” within the provided bathymetric void shapefile. Theme Global Change Master Directory (GCMD) Science Keywords EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION Theme Global Change Master Directory (GCMD) Science Keywords EARTH SCIENCE > OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > BATHYMETRY > COASTAL BATHYMETRY Theme Global Change Master Directory (GCMD) Science Keywords EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION Theme ISO 19115 Topic Category elevation Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA Spatial Global Change Master Directory (GCMD) Location Keywords VERTICAL LOCATION > LAND SURFACE Spatial Global Change Master Directory (GCMD) Location Keywords VERTICAL LOCATION > SEA FLOOR Instrument Global Change Master Directory (GCMD) Instrument Keywords LIDAR > Light Detection and Ranging Platform Global Change Master Directory (GCMD) Platform Keywords Airplane > Airplane Theme beach Theme erosion Office for Coastal Management Charleston SC Data Set Elevation None Planned Model (digital) Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners National Oceanic and Atmospheric Administration (NOAA), National Geodetic Survey (NGS), Remote Sensing Division (RSD), Coastal Mapping Program (CMP) 72007 Published / External Completed Other Yes Class table describing the class numbers used in the lidar data file. Each point in the lidar file has a class associated. 1 1 - Unclassified Point class number No No Active Unclassified point 2 2- Ground Point class number No No Active Ground Point 3 7 - Low Point (Noise) Point class number No No Active Low Point (Noise) 4 40 - Bathymetric Point Point class number No No Active Point classified as bathymetric ground. 5 43 - Submerged Object Point class number No No Active Submerged object, not otherwise specified (e.g., wreck, rock, submerged piling) 6 45 - Water Column Point class number No No Active Point classified as water column Data Steward 2021 Organization NOAA Office for Coastal Management NOAA/OCM coastal.info@noaa.gov 2234 South Hobson Ave Charleston SC 29405-2413 (843) 740-1202 https://coast.noaa.gov NOAA Office for Coastal Management Home Page Online Resource Distributor 2021 Organization NOAA Office for Coastal Management NOAA/OCM coastal.info@noaa.gov 2234 South Hobson Ave Charleston SC 29405-2413 (843) 740-1202 https://coast.noaa.gov NOAA Office for Coastal Management Home Page Online Resource Metadata Contact 2021 Organization NOAA Office for Coastal Management NOAA/OCM coastal.info@noaa.gov 2234 South Hobson Ave Charleston SC 29405-2413 (843) 740-1202 https://coast.noaa.gov NOAA Office for Coastal Management Home Page Online Resource Originator 2021 Organization National Geodetic Survey NGS https://ror.org/02f762h70 1315 East-West Hwy Silver Spring MD 20910 https://geodesy.noaa.gov/ Ground Condition -76.612 -76.1637 37.50013 37.03089 Range 2019-02-17 2019-04-12 No Yes No No No Geographic 3D EPSG:6319 NAD83(2011) NAD83 (National Spatial Reference System 2011) GRS 1980 6378137 298.257222101 1 Geodetic Latitude Lat degree north 2 Geodetic Longitude Lon degree east 3 Elipsoidal height h metre up Unclassified Data is available online for bulk or custom downloads None Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations. https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9287 2021 Organization NOAA Office for Coastal Management Customized Download Create custom data files by choosing data area, product type, map projection, file format, datum, etc. A new metadata will be produced to reflect your request using this record as a base. Change to an orthometric vertical datum is one of the many options. Zip Zip https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9287/index.html 2021 Organization NOAA Office for Coastal Management Bulk Download Bulk download of data files in LAZ format, geographic coordinates, orthometric heights. Note that the vertical datum (hence elevations) of the files here are different than described in this document. They will be in an orthometric datum. LAZ LAS/LAZ - LASer Zip https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9287/supplemental/extent_NGS_topobath_2018_gwynn2newportVA_m9287.kmz Browse graphic Browse Graphic KML This graphic displays the footprint for this lidar data set. https://coast.noaa.gov/dataviewer/ NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV) Online Resource HTML The Data Access Viewer (DAV) allows a user to search for and download elevation, imagery, and land cover data for the coastal U.S. and its territories. The data, hosted by the NOAA Office for Coastal Management, can be customized and requested for free download through a checkout interface. An email provides a link to the customized data, while the original data set is available through a link within the viewer. OS Independent Lidar horizontal accuracy is a function of Global Navigation Satellite System (GNSS) derived positional error, flying altitude, and INS derived attitude error. The obtained RMSEr value is multiplied by a conversion factor of 1.7308 to yield the horizontal component of the National Standards for Spatial Data Accuracy (NSSDA) reporting standard where a theoretical point will fall within the obtained radius 95 percent of the time (ACCr). Based on a flying altitude of 400 meters, an IMU error of 0.005 decimal degrees, and a GNSS positional error of 0.019 meters, the RMSEr value for The NOAA Chesapeake Bay VA1901 Option 3 West 1 project area is 0.65 meters, with a ACCr of 1.13 meters at the 95% confidence level. The project specification requires horizontal positions to be accurate to 1.0m(RMSE). Absolute accuracy was assessed using Non-Vegetated Vertical Accuracy (NVA) survey methods. Survey check points were evenly distributed as feasible throughout the project area. NVA compares known ground check point data that were withheld from the calibration and post-processing of the lidar point cloud to the triangulated surface generated by the ground-classified lidar point cloud. NVA is a measure of the accuracy of lidar point data in open areas with level slope (less than 20 degrees) where the lidar system has a high probability of measuring the ground surface and is evaluated at the 95% confidence interval (1.96*RMSE). In The NOAA Chesapeake Bay VA1901 Option 3 West 1 data extent, 30 survey checkpoints were used to assess the non-vegetated vertical accuracy. Project specifications require NVA meet 0.196 m accuracy at the 95% confidence interval. Submerged topography points were tested separately. In The NOAA Chesapeake Bay VA1901 Option 3 West 1 data extent, 45 survey checkpoints were used to assess the submerged topography accuracy. Project specifications require submerged topography shall meet a vertical RMSE of QL2b specified in the Draft National Coastal Mapping strategy 1.0 which is equivalent to 0.30 m RMSE at a depth of 1 m. Please refer to The NOAA Chesapeake Bay VA1901 Option 3 West 1 Topobathymetric lidar final data report for final accuracies, to be provided upon project completion. The NOAA Chesapeake Bay VA1901 Option 3 West 1 dataset Non-Vegetated Vertical Accuracy tested 0.084 m vertical accuracy at the 95% confidence level against the ground-classified lidar point cloud in open terrain using 30 ground check points, based on RMSEz (0.043 m) x 1.9600. The NOAA Chesapeake Bay VA1901 Option 3 West 1 dataset submerged topography accuracy tested 0.083 m vertical accuracy at the 95% confidence level against the classified points cloud using 45 submerged check points, based on RMSEz (0.043 m) x 1.9600. Submerged topography checkpoints usually occur in depths up to 1m. Data covers the project boundary. Not applicable Yes Unknown Yes NCEI-CO Data is backed up to tape and to cloud storage. Acquisition and Processing Organization NV5 Geospatial, Inc Originator 1 Data for The NOAA Chesapeake Bay VA1901 Option 3 West 1 Topobathymetric lidar project area was acquired by NV5 Geospatial, Inc. (NV5) using a Riegl VQ-880-GH Topobathymetric lidar system. All derived LAS data is referenced to: Horizontal Datum-NAD83(2011) epoch: 2010.00 Projection-UTM Zone 18N Horizontal Units-meters Vertical Datum-GRS80 Ellipsoid Vertical Units-meters The NOAA Chesapeake Bay VA1901 Option 3 West 1 dataset encompasses 4,821 - 500m x 500m tiles in an area encompassing a portion of the Chesapeake Bay and the nearby census designated places of Diggs, Matthews, Onemo, Susan, New Point, Seaford, Grafton, and Poquoson, Virginia. Lidar data were acquired with a VQ-880-GH Riegl sensor. The collected lidar data were immediately processed in the field by NV5 to a level that will allow QA\QC measures to determine if the sensor is functioning properly and assess the coverage of submerged topography. An initial SBET was created in POSPAC MMS 8.3 SP3 and loaded into RiProcess which applies pre-calibrated angular misalignment corrections of scanner position to extract the raw point cloud into geo-referenced LAS files. These files were inspected for sensor malfunctions and then passed through automated raster generation using LAStools to develop an initial assessment of bathymetric coverage. NV5 reviewed all acquired flight lines to ensure complete coverage and positional accuracy of the laser points. These rasters were also used to create an initial product in Quick Look Coverage Maps. These Quick Look files are not fully processed data or final products but provide rapid assessment of approximate coverage and depth penetration. NV5 resolved kinematic corrections for aircraft position data using aircraft GNSS and Applanix's proprietary PP-RTX solution. When PP-RTX was not used NV5 conducted static Global Navigation Satellite System (GNSS) ground surveys (1 Hz recording frequency) using base stations over known monument locations during flights. After the airborne survey, static GPS data were triangulated with nearby Continuously Operating Reference Stations (CORS) using the Online Positioning User Service (OPUS) for precise positioning. Multiple independent sessions over the same base station were performed to confirm antenna height measurements and to refine position accuracy. This data was used to correct the continuous on board measurements of the aircraft position recorded throughout the flight. A final smoothed best estimate trajectory (SBET) was developed that blends post-processed aircraft position with attitude data. Using the SBETs, sensor head position and attitude were then calculated throughout the survey. Trimble Business Center v.3.90, Blue Marble Geographic Calculator 2019, and PosPac MMS 8.3 SP3 were used for these processes. 2021-03-30T00:00:00 Organization NGS Communications and Outreach Branch ngs.infocenter@noaa.gov (301) 713-3242 (301) 713-4172 2 Following final SBET creation, NV5 used RiProcess 1.8.5 to calculate laser point positioning by associating SBET positions to each laser point return time, scan angle, and intensity. Terra 19 and LasTools were used to classify water surface and create a water surface model. They are created for single swaths to ensure temporal differences and wave or water surface height variations between flight lines do not impact the refraction of the bathymetric data. These models are used in NV5's LasMonkey refraction tool to determine the accurate positioning of bathymetric points. All lidar data below water surface models were classified as water column to be refracted. Light travels at different speeds in air versus water and its direction of travel or angle is changed or refracted when entering the water column. The refraction tool corrects for this difference by adjusting the depth (distance traveled) and horizontal positioning (change of angle/direction) of the lidar data. Using raster-based QC methods, the output data is verified to ensure the refraction tool functioned properly. Once all data was refracted by flight line data was exported to LAS 1.4 format and combined into 500 m x 500 m tiles. Data were then further calibrated using TerraMatch. NV5 used custom algorithms in TerraScan to classify the initial ground/submerged topography surface points. Relative accuracy of overlapping swaths was compared and verified through the use Delta-Z (DZ) orthos created using NV5's Las Product Creator. Absolute vertical accuracy of the calibrated data was assessed using ground survey data and complete coverage was again verified. Post automated classification NV5 then performed manual editing to review all classification and improve the final Topobathymetric surface. NV5's LasMonkey was used to update LAS header information, including all projection and coordinate reference system information. The lidar data are in LAS format 1.4 and point data record format 6. 1 - unclassified 2 - ground 7 - noise 40 - bathymetric bottom or submerged topography 43 - submerged feature 45 - water column 2021-03-30T00:00:00 3 The NOAA Office for Coastal Management (OCM) received files in laz format. The files contained lidar elevation and intensity measurements. The data were in UTM Zone 17 coordinates and ellipsoid elevations in meters. OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. Converted from UTM Zone 17 to geographic coordinates 2. Sorted by gps time Organization Office for Coastal Management OCM https://ror.org/05v14bq57 2234 South Hobson Avenue Charleston SC 29405-2413 https://www.coast.noaa.gov/ 72007 Entity gov.noaa.nmfs.inport:64533 Maryellen Sault 2021-04-13T17:45:15 SysAdmin InPortAdmin 2026-03-04T19:17:26 2022-03-16 National Geodetic Survey NGS 1002 Public No No 2022-03-16 1 Year 2023-03-16