49619 ak2007_aerometric_valdez_m1466_metadata Data Set Published / External 49401 Lidar - partner (no harvest) Project Completed 2013-02 This project was completed under USGS Contract No. 07CRCN0002, Task Order No. 070020009. This delivery contains point cloud data in LAS 1.1 format, classified in the following manner. Class 1: Unclassified, Class 2: Ground, Class 7: Low Point (Noise), Class 9: Water, Class 10: High Point (Noise), Class 12: Overlap, and Class 17: Port The following are the collection parameters and equipment used to create these data sets. Aircraft: Cessna 320 (N3443Q) and Piper Navajo (N6GR) Lidar System: Optech ALTM Gemini (03SEN145) Approximate Collection Altitude (Above Mean Terrain): 1800 meters Ground Speed: 145 kts Pulse Rate Frequency: 70 kHz Mirror Scan Frequency: 62.6 Hz Scan Angle (+/-): 5.3 degrees Beam Divergence: Narrow (0.25 mrad) Accuracy statements are based on areas of moderate terrain, with points classified as ground. Diminished accuracies are to be expected in areas of extreme terrain and dense vegetation. The accuracy of each point is expected to meet the vertical accuracy standard. Derived products may be less accurate in areas of extreme terrain and dense vegetation due to a lesser number of points defining the ground in these areas. Classified data sets such as this one may have varying posting due to some pulses not reaching the ground. Original contact information: Contact Name: Jacques Cloutier Contact Org: Aero-Metric, Inc. Title: Senior Geodetic Surveyor Phone: (907) 272-4495 Email: aerometric@aerometric-ak.com The purpose of this data set is to provide processed lidar data over Valdez at a nominal point spacing of 0.3 meter. 10263 A footprint of this data set may be viewed in Google Earth at: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/1466/supplemental/ak2007_aerometric_valdez_footprint.KMZ Theme ISO 19115 Topic Category elevation Theme Terrain Office for Coastal Management Charleston SC Data Set As Needed las Unclassified Lidar point cloud in LAS 1.1 format none Any conclusions drawn from the analysis of this information are not the responsibility of Aero-Metric Inc, NOAA, the Office for Coastal Management or its partners. Data Steward 2013-02 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 2013-02 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 2013-02 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 Point of Contact 2013-02 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 Ground Condition -146.641106 -145.913257 61.15846 61.036345 Discrete 2007-10-16 Discrete 2008-10-20 Discrete 2008-10-25 Discrete 2008-10-31 Yes Unclassified This data can be obtained on-line at the following URL: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=1466 ; 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. These data depict the heights at the time of the survey and are only accurate for that time. https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=1466 Customized Download Create custom data files by choosing data area, product type, map projection, file format, datum, etc. https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/1466/index.html Bulk Download Simple download of data files. https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/1466/supplemental/ak2007_aerometric_valdez_footprint.KMZ Browse Graphic Browse Graphic kmz This graphic shows topographic LiDAR coverage for Valdez, Alaska. https://coast.noaa.gov Online Resource https://coast.noaa.gov/dataviewer Online Resource 2016-05-23 Date that the source FGDC record was last modified. 2017-11-14 Converted from FGDC Content Standards for Digital Geospatial Metadata (version FGDC-STD-001-1998) using 'fgdc_to_inport_xml.pl' script. Contact Tyler Christensen (NOS) for details. 2018-02-08 Partial upload of Positional Accuracy fields only. 2018-03-13 Partial upload to move data access links to Distribution Info. Microsoft Windows 2000 Version 5.0 (Build 2195) Service Pack 4; lidarTools 1.0.9 All these data products were acquired at 1800 meters above mean terrain (AMT) and have a horizontal accuracy of 0.3 meter, with a nominal point spacing of 0.6 meters as per manufacturer's specifications, not field verified.; Quantitative Value: 0.3 meters, Test that produced the value: Compiled to meet value (meters) The final lidar data set was verified using 2554 GPS surveyed ground truth points. These points were collected by Aero-Metric along the roads throughout the developed areas of the project, using Real-Time Kinematic (RTK) GPS techniques. The ground truth points were compared against the lidar using TerraScan, which computes the difference between each ground truth point and the lidar generated surface. These differences are recorded in an output file in ASCII format. This file is imported into Microsoft Excel, where a statistical analysis is performed. The full lidar control check analysis is included in the deliverables for this project, named Valdez_Low_Altitude_QC_Results.pdf. We recommend additional ground truth surveys of the data set to verify the vertical accuracy has not changed due to natural causes, such as techtonic motion or freeze/thaw cycles, and non-natural causes such as road construction. Without ground truth survey checks this data is not recommended for design grade mapping or engineering. ; Quantitative Value: 0.092 meters, Test that produced the value: Consolidated vertical accuracy at the 95th percentile on road surfaces in meters Cloud Cover: 0 Complete Data has been verified using surveyed check points along road surfaces thoughout the project area. 1 System Calibration: Aero-Metric collected data over a previously surveyed area in Palmer, Alaska. Data was collected at the same settings as this project, using two intersecting perpendicular lines. Two GPS ground stations were operating on site in order to minimize GPS error. The data was classified in each line separately for ground and other common features between lines, such as building roofs. This data was processed in TerraMatch 8.001 (TerraSolid, Ltd.), to compute corrections for roll, pitch, heading, and mirror scale. These corrections were applied to the initial processing settings (.res file). The data was reprocessed to verify the corrections were applied properly. The corrected data was then compared to ground surveyed measurements in order to check for any consistent vertical bias. The final step in calibration verified there was minimal vertical noise due to changes in intensity. This was done by comparing elevations of points on the airport runway, one point on a runway stripe and another adjacent point on the pavement. 2008-10-18T00:00:00 10 The metadata was updated for Bounding coordinates, Spatial Reference info using FGDC template 2009-06-18T00:00:00 11 The NOAA Office for Coastal Management (OCM) received topographic files in LAS 1.1 format. The files contained lidar elevation and intensity measurements. The data were received in projected coordinates of NAD83 UTM6N, meters and were vertically referenced to NAVD88 orthometric elevations using GEOID06(Alaska). The vertical units of the data were meters. OCM performed the following processing for data storage and Digital Coast provisioning purposes: 1. LAS Classifications 11(first return only), 13(first of many returns), 14(second of many returns), 15(third of many returns), 16(last of many returns) were all placed into Class 1 (Unclassified) 2. The topographic las files were converted from Projected Coordinates (NAD83 UTM6N, meters) to Geographic Coordinates (NAD83, decimal degrees). 3. The topographic las files were vertically converted from orthometric elevations (NAVD88) to ellipsoidal elevations (NAD83) using GEOID06. 2013-02-01T00:00:00 2 Create a smoothed-best estimated trajectory (SBET) of the sensor at a rate of 200 Hz, by integrating the airborne GPS and IMU data. The basis of the GPS coordinates were computed using NGS OPUS, and were referenced to NAD83 (CORS96) with GEOID06 derived orthometric heights. The maximum baseline distance for this project was 30 km, the average base line length was 12 km. The mean GPS positional accuracy for this project was +/- 0.08 meters. 2008-11-02T00:00:00 3 Integrate SBET and raw laser data to produce point cloud data in LAS 1.1 format for each flight line. 2008-11-02T00:00:00 4 Compute the roll, pitch, heading, and mirror scale correction factors for each flight line, then apply corrections to the corresponding flight line. 2009-01-15T00:00:00 5 Automated classification of the bare-earth data from the lidar point cloud using a series of algorithms customized for the types of terrain encountered in the project. 2009-01-16T00:00:00 6 Manual classification of any data which appears to be bare-earth but was not properly classified using the automated methods. 2009-03-20T00:00:00 7 The shorelines of the lakes and port areas were determined using manual techniques, starting with digitized shorelines from the orthophotography of the project area. The lidar points then underwent an intensive manual edit to determine with greater accuracy the points which represented the water surface. For the final data products the mean elevation of the water on each lake was used to determine its fixed elevation. The port areas fixed elevation was determined using the highest water point in the port data set. This value was found to be 4.72 meters. All points below 4.72 meters in the port area were fixed to this elevation, as per the contract. 2009-05-25T00:00:00 8 Create point clouds in LAS 1.1 format for all returns. 2009-05-26T00:00:00 9 Data verified using survey control points, located throughout the area. 2009-05-27T00:00:00 gov.noaa.nmfs.inport:49619 Anne Ball 2017-11-15T15:21:14 SysAdmin InPortAdmin 2022-08-09T17:11:37 2022-03-16 OCM Partners OCMP 1002 Public No No 2022-03-16 1 Year 2023-03-16