2020 Lidar: Santa Clara County, CA
Data Set (DS) | OCM Partners (OCMP)GUID: gov.noaa.nmfs.inport:64802 | Updated: October 17, 2023 | Published / External
Item Identification
Title: | 2020 Lidar: Santa Clara County, CA |
---|---|
Short Name: | ca2020_santa_clara_m9329_metadata |
Status: | Completed |
Publication Date: | 2020-10-19 |
Abstract: |
Product: These lidar data are processed Classified LAS 1.4 files, formatted to 8183 individual 2500 ft x 2500 ft tiles; used to create intensity rasters, 3D breaklines and hydro-flattened DEMs as necessary. Geographic Extent: Santa Clara county, California, covering approximately 1771 square miles. Dataset Description: The lidar project called for the Planning, Acquisition, processing and derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.35 meters. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 2.1. Lidar data was delivered as processed Classified LAS 1.4 files, formatted to 8185 individual 2500 ft x 2500 ft tiles, as tiled intensity rasters, and as tiled bare-earth DEMs; all tiled to the same 2500 ft x 2500 ft schema. Ground Conditions: Lidar was collected in early 2020, while no snow was on the ground and rivers were at or below normal levels. In order to post process the lidar data to meet task order specifications and meet ASPRS vertical accuracy guidelines, Sanborn Map Company, Inc., utilized a total of 25 ground control points that were used to calibrate the lidar to known ground locations established throughout the project area. An additional 125 independent accuracy checkpoints, 70 in Bare Earth and Urban landcovers (70 NVA points), 55 in Tall Grass and Brushland/Low Trees categories (55 VVA points), were used to assess the vertical accuracy of the data. These check points were not used to calibrate or post process the data. The NOAA Office for Coastal Management (OCM) downloaded 8183 laz point data files from this USGS site: ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/CA_SantaClaraCounty_2020_A20/CA_SantaClaraCounty_2020/LAZ/ The data were processed to the Data Access Viewer (DAV) and http. In addition to these lidar point data, the bare earth Digital Elevation Models (DEM) created from the lidar point data and the hydro breaklines are also available for download. These data are available for download at the links provided in the URL section of this metadata record. Please note that these products have not been reviewed by the NOAA Office for Coastal Management (OCM) and any conclusions drawn from the analysis of this information are not the responsibility of NOAA or OCM. |
Purpose: |
To acquire detailed surface elevation data for use in conservation planning, design, research, floodplain mapping, dam safety assessments and elevation modeling, etc. Classified LAS files are used to show the manually reviewed bare earth surface. This allows the user to create Intensity Images, Breaklines and Raster DEM. The purpose of these lidar data was to produce high accuracy 3D hydro-flattened Digital Elevation Model (DEM) with a 1 foot cell size. These lidar point cloud data were used to create intensity images, 3D breaklines, and hydro-flattened DEMs as necessary. |
Supplemental Information: |
USGS Contract No. G16PC00051 CONTRACTOR: Sanborn Map Company, Inc. All follow-on processing was completed by the prime contractor. The following are the USGS lidar fields in JSON: {
"ldrinfo" : {
"ldrspec" : "U.S. Geological Survey (USGS) - National Geospatial Program (NGP) Lidar Base Specification v2.1", "ldrsens" : "Leica TerrainMapper", "ldrmaxnr" : "15", "ldrnps" : "0.31", "ldrdens" : "10.4", "ldranps" : "0.31", "ldradens" : "10.4", "ldrfltht" : "2040", "ldrfltsp" : "160", "ldrscana" : "40", "ldrscanr" : "150.0", "ldrpulsr" : "1500.0", "ldrpulsd" : "4", "ldrpulsw" : "0.48", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.25", "ldrswatw" : "1485", "ldrswato" : "20", "ldrgeoid" : "National Geodetic Survey (NGS) Geoid18" }, "ldraccur" : {
"ldrchacc" : "0.5", "rawnva" : "0.093", "rawnvan" : "70", "clsnva" : "0.093", "clsnvan" : "70", "clsvva" : "0.125", "clsvvan" : "55" }, "lasinfo" : {
"lasver" : "1.4", "lasprf" : "6", "laswheld" : "Withheld (ignore) points were identified in these files using the standard LAS Withheld bit.", "lasolap" : "Swath "overage" points were identified in these files using the standard LAS overlap bit.", "lasintr" : "16", "lasclass" : {
"clascode" : "1", "clasitem" : "Processed, but Unclassified" }, "lasclass" : {
"clascode" : "2", "clasitem" : "Bare Earth Ground" }, "lasclass" : {
"clascode" : "3", "clasitem" : "Low Vegetation" }, "lasclass" : {
"clascode" : "4", "clasitem" : "Medium Vegetation" }, "lasclass" : {
"clascode" : "5", "clasitem" : "High Vegetation" }, "lasclass" : {
"clascode" : "6", "clasitem" : "Building" }, "lasclass" : {
"clascode" : "7", "clasitem" : "Low Noise" }, "lasclass" : {
"clascode" : "9", "clasitem" : "Water" }, "lasclass" : {
"clascode" : "17", "clasitem" : "Bridge Decks" }, "lasclass" : {
"clascode" : "18", "clasitem" : "High Noise" }, "lasclass" : {
"clascode" : "20", "clasitem" : "Ignored Ground" }, "lasclass" : {
"clascode" : "21", "clasitem" : "Snow" }, "lasclass" : {
"clascode" : "22", "clasitem" : "Temporal Exclusion" } }} |
Keywords
Theme Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION
|
ISO 19115 Topic Category |
elevation
|
UNCONTROLLED | |
None | erosion |
Spatial Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > CALIFORNIA
|
Global Change Master Directory (GCMD) Location Keywords |
VERTICAL LOCATION > LAND SURFACE
|
UNCONTROLLED | |
None | Continent > North America > United States Of America > California > Santa Clara County |
Instrument Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Instrument Keywords |
LIDAR > Light Detection and Ranging
|
Platform Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Platform Keywords |
Airplane > Airplane
|
Physical Location
Organization: | Office for Coastal Management |
---|---|
City: | Charleston |
State/Province: | SC |
Data Set Information
Data Set Scope Code: | Data Set |
---|---|
Data Set Type: | Elevation |
Maintenance Frequency: | None Planned |
Data Presentation Form: | Model (digital) |
Distribution Liability: |
Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners. |
Data Set Credit: | Sanborn Map Company, Inc. |
Support Roles
Data Steward
Date Effective From: | 2021 |
---|---|
Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Distributor
Date Effective From: | 2021 |
---|---|
Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Metadata Contact
Date Effective From: | 2021 |
---|---|
Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Point of Contact
Date Effective From: | 2021 |
---|---|
Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Extents
Currentness Reference: | Ground Condition |
---|
Extent Group 1
Extent Group 1 / Geographic Area 1
W° Bound: | -122.2517701747 | |
---|---|---|
E° Bound: | -121.1604881458 | |
N° Bound: | 37.5246275052 | |
S° Bound: | 36.8544593422 |
Extent Group 1 / Time Frame 1
Time Frame Type: | Range |
---|---|
Start: | 2020-04-03 |
End: | 2020-04-22 |
Spatial Information
Spatial Resolution
Horizontal Distance: | 0.35 Meter |
---|
Spatial Representation
Representations Used
Grid: | No |
---|---|
Vector: | Yes |
Text / Table: | No |
TIN: | No |
Stereo Model: | No |
Video: | No |
Reference Systems
Reference System 1
Coordinate Reference System |
|||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Access Information
Security Class: | Unclassified |
---|---|
Data Access Procedure: |
Data is available online for bulk and custom downloads. |
Data Access Constraints: |
None |
Data Use Constraints: |
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. |
Distribution Information
Distribution 1
Start Date: | 2021-06-17 |
---|---|
End Date: | Present |
Download URL: | https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9329/details/9329 |
Distributor: | NOAA Office for Coastal Management (NOAA/OCM) (2021 - Present) |
File Name: | Customized Download |
Description: |
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. |
File Type (Deprecated): | Zip |
Compression: | Zip |
Distribution 2
Start Date: | 2021-06-17 |
---|---|
End Date: | Present |
Download URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9329/index.html |
Distributor: | NOAA Office for Coastal Management (NOAA/OCM) (2021 - Present) |
File Name: | Bulk Download |
Description: |
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. |
File Type (Deprecated): | LAZ |
Distribution Format: | LAS/LAZ - LASer |
Compression: | Zip |
URLs
URL 1
URL: | https://coast.noaa.gov/dataviewer/ |
---|---|
Name: | NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV) |
URL Type: |
Online Resource
|
File Resource Format: | HTML |
Description: |
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. |
URL 2
URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9329/supplemental/ca2020_santa_clara_m9329.kmz |
---|---|
Name: | Browse graphic |
URL Type: |
Browse Graphic
|
File Resource Format: | KML |
Description: |
This graphic displays the footprint for this lidar data set. |
URL 3
URL: | https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9330/details/9330 |
---|---|
Name: | Custom DEM Download |
URL Type: |
Online Resource
|
File Resource Format: | Zip |
Description: |
Link to custom download, from the Data Access Viewer (DAV), the raster Digital Elevation Model (DEM) data that were created from this lidar data set. |
URL 4
URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9329/supplemental/USGS_CA_SantaClaraCounty_2020_Summary_Report.pdf |
---|---|
Name: | USGS Data Validation Report |
URL Type: |
Online Resource
|
File Resource Format: | |
Description: |
Link to the USGS Data Validation Report. |
URL 5
URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9329/supplemental/312020310_SantaClara_County_CA_2020_LidarReport.pdf |
---|---|
Name: | Lidar Report |
URL Type: |
Online Resource
|
File Resource Format: | |
Description: |
Link to the Sanborn lidar report. |
URL 6
URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9329/supplemental/CA_SantaClaraCounty_2020_A20_WP_Report.pdf |
---|---|
Name: | USGS Vertical Accuracy Report |
URL Type: |
Online Resource
|
File Resource Format: | |
Description: |
Link to the USGS vertical accuracy report. |
URL 7
URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9329/breaklines/ |
---|---|
Name: | Hydro Breaklines |
URL Type: |
Online Resource
|
File Resource Format: | Zip |
Description: |
Link to the hydro breaklines. |
URL 8
URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9329/supplemental/USGS_CA_SantaClaraCounty_2020_FINAL_lasqc.txt |
---|---|
Name: | USGS LAS QC Report |
URL Type: |
Online Resource
|
File Resource Format: | txt |
Description: |
Link to the USGS LAS QC Report. |
Technical Environment
Description: |
Leica HxMap v2.7.0; GeoCue v2017.1.14.1; Windows 10 Operating System |
---|
Data Quality
Vertical Positional Accuracy: |
This data set was tested to meet ASPRS Positional Accuracy Standard for Digital Geospatial Data (2014) for a 10cm RMSEz Vertical Accuracy Class. Actual NVA accuracy was found to be RMSEz = 4.72cm, equating to +/- 9.27cm at 95% confidence level. Actual VVA accuracy was found to be +/- 12.50cm at the 95th percentile. USGS Determined Vertical Accuracy Tested NVA = 9.40 cm at 95% Confidence Level (4.8 cm RMSE) Tested VVA = 12.48 cm at 95th Percentile Please see the USGS Work Package Report for more information. The link to this report is provided in the URL section of this metadata record. |
---|---|
Completeness Report: |
These LAS data files include all data points collected. No points have been removed or excluded. A visual qualitative assessment was performed to ensure data completeness. No void areas or missing data exist. The raw point cloud is of good quality and data passes Non-Vegetated Vertical Accuracy specifications. |
Conceptual Consistency: |
Data covers the entire area specified for this project. |
Data Management
Have Resources for Management of these Data Been Identified?: | Yes |
---|---|
Approximate Percentage of Budget for these Data Devoted to Data Management: | Unknown |
Do these Data Comply with the Data Access Directive?: | Yes |
Actual or Planned Long-Term Data Archive Location: | NCEI-CO |
How Will the Data Be Protected from Accidental or Malicious Modification or Deletion Prior to Receipt by the Archive?: |
Data is backed up to tape and to cloud storage. |
Lineage
Lineage Statement: |
Data were collected and processed by Sanborn Map Company, Inc. and made available on the USGS ftp site. The data were downloaded from the USGS ftp site by the NOAA Office for Coastal Management (OCM) where the data were processed to make it available for custom download from the Data Access Viewer (DAV) and bulk download from https. |
---|
Sources
Sanborn Map Company, Inc.
U.S. Geological Survey (USGS)
Process Steps
Process Step 1
Description: |
The boresight was completed prior to project execution. The following steps describe the Raw Data Processing process: 1) Technicians processed the raw data to LAS format flight lines using the final GNSS/IMU solution. This LAS data set was used as source data for lidar matching. 2) Technicians utilized commercial and proprietary software packages to analyze how well flight line overlaps match for the entire lift and adjusted as necessary until the results met the project specifications. 3) Once all lifts were completed with lidar matching, the technicians checked and corrected the vertical misalignment of all flight lines and also the matching between data and ground truth. The relative accuracy was less than or equal to 6 cm RMSEz within individual swaths and less than or equal to 8 cm RMSEz or within swath overlap (between adjacent swaths). 4) The technicians ran a final vertical accuracy check of the flight lines against the surveyed check points after the z correction to ensure the requirement of NVA = 19.6 cm 95% Confidence Level (Required Accuracy) was met. Point classification was performed according to USGS Lidar Base Specification v2.1, and breaklines were collected for water features. Bare-earth DEMs were exported from the classified point cloud using collected breaklines for hydroflattening. |
---|---|
Process Date/Time: | 2020-01-01 00:00:00 |
Process Step 2
Description: |
LAS Point Classification: The point classification is performed as described below. The bare-earth surface is then manually reviewed to ensure correct classification on the Class 2 (Ground) points. After the bare-earth surface is finalized, it is then used to generate all hydro-breaklines through heads-up digitization. All Class 2 (Ground) lidar data inside of the Lake Pond and Double Line Drain hydro-flattened breaklines were then classified to Class 9 (Water) using LP360 functionality. A buffer of 1 foot was also used around each hydro-flattened feature to classify these Class 2 (Ground) points to Class 20 (Ignored Ground). All Lake Pond Island and Double Line Drain Island features were checked to ensure that the Class 2 (Ground) points were reclassified to the correct classification after the automated classification was completed. All overlap data was processed through automated functionality provided by TerraScan to classify the overlapping flight line data to approved classes by USGS. The overlap data was classified using standard LAS overlap bit. These classes were created through automated processes only and were not verified for classification accuracy. Due to software limitations within TerraScan, these classes were used to trip the withheld bit within various software packages. These processes were reviewed and accepted by USGS through numerous conference calls and pilot study areas. All data was manually reviewed and any remaining artifacts removed using functionality provided by LP360, TerraScan and TerraModeler. Global Mapper was used as a final check of the bare-earth dataset. GeoCue was then used to create the deliverable industry-standard LAS files. Sanborn Map Company, Inc. proprietary software was used to perform final statistical analysis of the classes in the LAS files, on a per tile level to verify final classification metrics and full LAS header information. |
---|---|
Process Date/Time: | 2020-10-18 00:00:00 |
Process Step 3
Description: |
Data was tested at 0.21 meter aggregate nominal pulse spacing and at 22.5 aggregate points per meter. The aggregate nominal pulse spacing was tested on classified tiled LAS using geometrically reliable first-return points without overlap. ANPS was tested using Delaunay Triangulation that produced average point spacing between all nearest neighbors. |
---|---|
Process Date/Time: | 2020-10-16 00:00:00 |
Process Step 4
Description: |
The NOAA Office for Coastal Management (OCM) downloaded 8183 laz point data files from this USGS site: ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/CA_SantaClaraCounty_2020_A20/CA_SantaClaraCounty_2020/LAZ/. The data were in CA State Plane Region 3 FIPS 0403 (NAD83 2011), US survey feet coordinates and NAVD88 (Geoid18) elevations in feet. The data were classified as: 1 - Unclassified, 2 - Ground, 3 - Low Vegetation, 4 - Medium Vegetation, 5 - High Vegetation, 6 - Buildings, 7 - Low Noise, 9 - Water, 17 - Bridge Decks, 18 - High Noise, 20 - Ignored Ground. OCM processed all classifications of points to the Digital Coast Data Access Viewer (DAV). Classes available on the DAV are: 1, 2, 3, 4, 5, 6, 7, 9,17, 18, 20. OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. Internal OCM scripts were run to check the number of points by classification and by flight ID and the gps, elevation, and intensity ranges. 2. Internal OCM scripts were run on the laz files to: a. Convert from orthometric (NAVD88) elevations to NAD83 (2011) ellipsoid elevations using the Geoid18 model b. Convert the laz files from CA State Plane Region 3 (NAD83 2011), US survey feet coordinates to geographic coordinates c. Convert from vertical units of feet to vertical units of meters. d. Filter points with elevation values less than -25 ft and greater than 5000 ft. e. Filter points outside the geographic range of the bounding coordinates of -36.5, -122.5, 38, -121 degrees f. Assign the geokeys, sort the data by gps time and zip the data to database and to http. |
---|---|
Process Contact: | Office for Coastal Management (OCM) |
Catalog Details
Catalog Item ID: | 64802 |
---|---|
GUID: | gov.noaa.nmfs.inport:64802 |
Metadata Record Created By: | Rebecca Mataosky |
Metadata Record Created: | 2021-06-17 18:10+0000 |
Metadata Record Last Modified By: | SysAdmin InPortAdmin |
Metadata Record Last Modified: | 2023-10-17 16:12+0000 |
Metadata Record Published: | 2022-03-16 |
Owner Org: | OCMP |
Metadata Publication Status: | Published Externally |
Do Not Publish?: | N |
Metadata Last Review Date: | 2022-03-16 |
Metadata Review Frequency: | 1 Year |
Metadata Next Review Date: | 2023-03-16 |