Short Citation:
OCM Partners, 2021: 2015 - 2016 LARIAC Lidar DEM: Los Angeles Region, CA, https://www.fisheries.noaa.gov/inport/item/55257.

Item Identification

Title: 2015 - 2016 LARIAC Lidar DEM: Los Angeles Region, CA
Short Name: ca2015_la_dem_m8659_metadata
Status: Completed
Publication Date: 2017-04-20
Abstract:

This raster dataset contains LiDAR-derived elevation data flown from Fall 2015 to Spring 2016, with additional reflights through Fall 2016. This dataset encompasses all of the LARIAC4 project, comprised of approximately 4214 square miles.

The NOAA Office for Coastal Management (OCM) downloaded this digital elevation model (DEM) data from the USGS site: ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/Elevation/OPR/CA_LosAngeles_2016// and processed the data to be available on the Digital Coast Data Access Viewer (DAV).

In addition to these bare earth Digital Elevation Model (DEM) data, the lidar point data that these DEM data were created from, are also available. These data are available for custom download at the link provided in the URL section of this metadata record.

Breakline data are also available. These data are are available for download at the link provided in the URL section of this metadata record. 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:

The purpose of this dataset is to create a representation of the topology of the study area with all vegetation and man-made structures removed. In addition, this dataset was used for creation and QC of contours and hydro-breaklines, in tandem with the raw LiDAR data.

Supplemental Information:

CONTRACTOR: Pictometry International, Inc.

Keywords

Theme Keywords

Thesaurus Keyword
UNCONTROLLED
Global Change Master Directory (GCMD) Science Keywords Earth Science > Land Surface > Topography > Terrain Elevation
Global Change Master Directory (GCMD) Science Keywords Earth Science > Oceans > Coastal Processes > Coastal Elevation
Global Change Master Directory (GCMD) Science Keywords elevation
None Bare earth
None DEM
None Digital Elevation Model
None lidar
None Topography

Spatial Keywords

Thesaurus Keyword
UNCONTROLLED
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
None Los Angeles
None Los Angeles County
None Santa Catalina Island
None U.S. Coastline

Instrument Keywords

Thesaurus Keyword
UNCONTROLLED
Global Change Master Directory (GCMD) Instrument Keywords Earth Remote Sensing Instruments > Active Remote Sensing > Profilers/Sounders > Lidar/Laser Sounders > LIDAR > Light Detection and Ranging

Platform Keywords

Thesaurus Keyword
UNCONTROLLED
Global Change Master Directory (GCMD) Platform Keywords Aircraft > Aircraft

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:

In no event shall the creators, custodians, or distributors of these data be liable for any damages arising out of its use, or from the inability of the customer to use these data for their intended application.

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

Data Set Credit: Pictometry International, Inc., LARIAC

Support Roles

Data Steward

CC ID: 808956
Date Effective From: 2018-12-14
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

CC ID: 808957
Date Effective From: 2018-12-14
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

CC ID: 808958
Date Effective From: 2018-12-14
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

CC ID: 808959
Date Effective From: 2018-12-14
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

CC ID: 808962
W° Bound: -118.9593531
E° Bound: -117.63773
N° Bound: 34.8263383
S° Bound: 33.2916879

Extent Group 1 / Time Frame 1

CC ID: 808961
Time Frame Type: Range
Start: 2015-09-27
End: 2016-10-18

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

CC ID: 808963
Start Date: 2018-12-14
End Date: Present
Download URL: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=8659
Distributor: NOAA Office for Coastal Management (NOAA/OCM) (2018-12-14 - Present)
File Name: Customized Download
Description:

Create custom data files by choosing data area, map projection, file format, etc. A new metadata will be produced to reflect your request using this record as a base.

Compression: Zip

Distribution 2

CC ID: 808964
Start Date: 2018-12-14
End Date: Present
Download URL: https://coast.noaa.gov/htdata/raster2/elevation/CA_Los_Angeles_DEM_2015_8659
Distributor: NOAA Office for Coastal Management (NOAA/OCM) (2018-12-14 - Present)
File Name: Bulk Download
Description:

Bulk download of data files in the original coordinate system.

URLs

URL 1

CC ID: 808951
URL: https://coast.noaa.gov/
Name: NOAA's Office for Coastal Management (OCM) website
URL Type:
Online Resource
File Resource Format: HTML
Description:

Information on the NOAA Office for Coastal Management (OCM)

URL 2

CC ID: 808952
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 3

CC ID: 808953
URL: https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/8651/supplemental/ca2015_la_m8651.kmz
Name: Browse graphic
URL Type:
Browse Graphic
File Resource Format: KML
Description:

This graphic displays the footprint for this lidar data set.

URL 4

CC ID: 808954
URL: https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/8651/supplemental/Project_Report.pdf
Name: Dataset report
URL Type:
Online Resource
File Resource Format: PDF
Description:

Link to data set report.

URL 5

CC ID: 809125
URL: https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/8651/supplemental/Lariac_USGS_vertical_accuracy_report.pdf
URL Type:
Online Resource
Description:

Link to the vertical accuracy report.

URL 6

CC ID: 809126
URL: https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/8651/breaklines/
URL Type:
Online Resource
Description:

Link to the breakline data.

URL 7

CC ID: 809127
URL: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=8651
URL Type:
Online Resource
Description:

Link to custom download the lidar point data from which these raster Digital Elevation Model (DEM) data were created.

Technical Environment

Description:

Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.2.1.3497

Data Quality

Vertical Positional Accuracy:

The same 212 checkpoints that were used to test the vertical accuracy of the lidar, were used to validate the vertical accuracy of the final DEM products as well. Accuracy results may vary between the source lidar and final DEM deliverable. DEMs are created by averaging several lidar points within each pixel which may result in slightly different elevation values at each survey checkpoint when compared to the source LAS, which does not average several lidar points together but may interpolate (linearly) between two or three points to derive an elevation value. The vertical accuracy of the DEM is tested by extracting the elevation of the pixel that contains the x/y coordinates of the checkpoint and comparing these DEM elevations to the surveyed elevations. Dewberry typically uses LP360 software to test the swath lidar vertical accuracy, Terrascan software to test the classified lidar vertical accuracy, and Esri ArcMap to test the DEM vertical accuracy so that three different software programs are used to validate the vertical accuracy for each project.

This DEM dataset was tested to meet ASPRS Positional Accuracy Standards for Digital Geospatial Data (2014) for a 10 cm (0.33 ft) RMSEz Vertical Accuracy Class. Actual NVA accuracy was found to be RMSEz = 0.31 ft (9.4 cm), equating to +/- 0.60 ft (18.2 cm) at 95% confidence level. Actual VVA accuracy was found to be +/- 0.52 ft (15,8 cm) at the 95th percentile.

Completeness Report:

LiDAR intensity values were captured at 12-bit levels and scaled down to 8-bit during processing of the intensity raster.

Conceptual Consistency:

Data cover the entire area specified for this project.

Lineage

Sources

Ground Control for Los Angeles County, CA LARIAC4 lidar project.

CC ID: 808945
Contact Name: Red Plains Survey Company
Publish Date: 2015-11-02
Extent Type: Discrete
Extent Start Date/Time: 2015-11-02
Source Contribution:

This data source was used (along with the airborne GPS/IMU data) to georeference the lidar point cloud data.

LA County GCP Report 2015.pdf

CC ID: 808946
Contact Name: LAR-IAC
Extent Type: Discrete
Extent Start Date/Time: 2017-04-20
Source Contribution:

Laser data derived from aerial survey

Lidar Intensity Imagery for Los Angeles County, CA

CC ID: 808947
Contact Name: Pictometry International
Publish Date: 2017-04-20
Source Contribution:

This data source was used to verify proper sensor operation.

Process Steps

Process Step 1

CC ID: 808948
Description:

Lidar Preprocessing: Airborne GPS and IMU data were merged to develop a Single Best Estimate (SBET) of the lidar system trajectory for each lift. Lidar ranging data were initially calibrated using previous best parameters for this instrument and aircraft. Relative calibration was evaluated using advanced plane-matching analysis and parameter corrections were derived. This relative calibration was repeated iteratively until residual errors between overlapping swaths, across all project lifts, was reduced to 3 cm or less. Data were then block adjusted to match surveyed calibration control.

Process Date/Time: 2016-02-26 00:00:00

Process Step 2

CC ID: 808949
Description:

Lidar Post-Processing: After generation of the calibrated point cloud data in LAS format from Optech's Lidar Mapping Suite (LMS), the data is imported into the TerraSolid software suite (running under Bentley’s MicroStation) for matching and classification. Upon import, the data is divided into tiles for the purpose of creating more manageable data. Once imported to TerraSolid, blocks of data containing overlapping flight lines are selected. The data in these blocks is analyzed by TerraMatch and adjustments to the roll, pitch, heading, and scale that minimize any data misalignment between the flight lines are computed. These adjustments are then applied to the entire mission’s worth of data. Data across the mission is then manually reviewed to ensure proper alignment between flightlines has been achieved. This process is then repeated for each mission; once complete, intra-sortie alignment is verified.

Process Date/Time: 2017-04-20 00:00:00

Process Step 3

CC ID: 809129
Description:

The NOAA Office for Coastal Management (OCM) downloaded 13810 CA_LosAngeles_2016/ Digital Elevation Model (DEM) files from this USGS site: ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/Elevation/OPR/ and processed the data to the Data Access Viewer (DAV). The data were in CA State Plane Zone 5 coordinates and NAVD88 (Geoid12B) elevations in feet. The bare earth raster files were at a 1 meter grid spacing.

OCM performed the following processing on the data for Digital Coast storage and provisioning purposes:

1. Converted the files from elevations in feet to meters using gdal_translate.

2. Copied the files to https

Process Date/Time: 2018-12-14 00:00:00
Process Contact: Office for Coastal Management (OCM)

Catalog Details

Catalog Item ID: 55257
Metadata Record Created By: Rebecca Mataosky
Metadata Record Created: 2018-12-14 10:56+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2019-07-02 15:17+0000
Metadata Record Published: 2018-12-17
Owner Org: OCMP
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Next Review Date: 2019-12-18