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Short Citation:
OCM Partners, 2023: September 2004 Lidar Point Data of Southern California Coastline: Long Beach to US/Mexican Border,

Item Identification

Title: September 2004 Lidar Point Data of Southern California Coastline: Long Beach to US/Mexican Border
Short Name: scripps_20040928_m51_metadata
Status: Completed
Publication Date: 2005-04-06

This data set contains lidar point data (Geodetic Coordinates) from a strip of Southern California

coastline (including water, beach, cliffs, and top of cliffs) from Long Beach to the US/Mexico border. The data set was created

by combining data collected using an Optech Inc. Airborne Laser Terrain Mapper (ALTM) 1225 in combination with geodetic quality

Global Positioning System (GPS) airborne and ground-based receivers. The Bureau of Economic Geology, the University of Texas at

Austin owns and operates an ALTM 1225 system (serial number 99d118). The system was installed in a twin engine Partenavia P-68

(tail number N6602L) owned and operated by Aspen Helicopter, Inc. The lidar data set described by this document was collected

on 28-30 September 2004; Julian Days 27204, 27304, and 27404 (see Lineage, Source_Information, Source_Contribution for pass

information). 99d118 instrument settings for these flights were; laser pulse rate: 25kHz, scanner rate: 26Hz, scan angle:

+/- 20deg, beam divergence: narrow, altitude: 950-1150m AGL, and ground speed: 90-132kts. Settings were different on final

day of surveying due to low clouds and flight restrictions: beam divergence: wide, altitude: 320-620m AGL, and ground speed:

101-121kts. Three GPS base stations (Seal Beach, Dana Point, and Point Loma, see Lineage, Source_Information, Source_Contribution

for coordinates) were operating during the survey. Data represented is all points including terrain, vegetation, and structures.

This data also contains returns from the water surface. No processing has been done to remove returns from terrain, vegetation,

structures or water surfaces.

Original contact information:

Contact Name: Julie Thomas/Randy Bucciarelli

Contact Org: SCBPS/CDIP, Scripps Institution of Oceanography

Title: Project Managers

Phone: 858-534-3032


The data described in this document will be compared with previous and forthcoming data sets to determine rates of

shoreline change along the Southern California coastline. The SCBPS program is designed to improve the understanding of beach

sand transport by waves and currents, thus improving local and regional coastal management.



Other Citation Details:

quad names (from north to south): Long Beach, Los Alamitos, Long Beach OE S, Seal Beach, Newport Beach, Newport Beach OE S,

Laguna Beach, San Juan Capistrano, Dana Point, San Clemente, San Onofre Bluff, Las Pulgas Canyon, Oceanside, San Luis Rey,

Encinitas, Del Mar OE W, Del Mar, La Jolla OE W, La Jolla, Point Loma OE W, Point Loma, Imperial Beach OE W, Imperial Beach

Supplemental Information:

The ALTM 1225 (SN#99d118) lidar instrument has the following specifications: operating altitude = 410-2,000 m AGL; maximum

laser pulse rate = 25 kHz; laser scan angle = variable from 0 to +/-20 deg from nadir; scanning frequency = variable, 28 Hz at

the 20 deg scan angle; and beam divergence: narrow = 0.2 milliradian (half angle, 1/e). The ALTM 1225 does not digitize and record

the waveform of the laser reflection, but records the range and backscatter intensity of the first and last laser reflection

using a constant-fraction discriminator and two Timing Interval Meters (TIM).

ALTM elevation points are computed using three sets of data: laser ranges and their associated scan angles, platform position

and orientation information, and calibration data and mounting parameters (Wehr and Lohr, 1999). Global Positioning System (GPS)

receivers in the aircraft and on the ground provide platform positioning. The GPS receivers record pseudo-range and phase

information for post-processing. Platform orientation information comes from an Inertial Measurement Unit (IMU) containing

three orthogonal accelerometers and gyroscopes. An aided-Inertial Navigation System (INS) solution for the aircraft's attitude

is estimated from the IMU output and the GPS information.

Wehr, A. and U. Lohr, 1999, Airborne laser scanning - an introduction and overview, ISPRS Journal of Photogrammetry and

Remote Sensing, vol. 54, no.2-3, pp.68-82.


Theme Keywords

Thesaurus Keyword
ISO 19115 Topic Category
None beach
None intensity
None Latitude
None Longitude
None point file
None shoreline

Temporal Keywords

Thesaurus Keyword
None 2004
None September

Physical Location

Organization: Office for Coastal Management
City: Charleston
State/Province: SC

Data Set Information

Data Set Scope Code: Data Set
Maintenance Note:

None planned, as needed

Distribution Liability:

This data was collected in partnership with Scripps Institution of Oceanography,

The University of California, San Diego. Any conclusions drawn from analysis of this information are not the responsibility

of the Bureau of Economic Geology or the University of Texas at Austin, NOAA, the OCM or its partners.

Data Set Credit: SCBPS/CDIP is jointly funded by the US Army Corps of Engineers and the California Department of Boating and Waterways. The initial data are collected by Bureau of Economic Geology, The University of Texas at Austin: R. Gutierrez and T. Hepner. Center for Space Research, The University of Texas at Austin: A. Neuenschwander. Data are further classified and processed by the SCBPS group, located at the Scripps Institution of Oceanography.

Support Roles

Data Steward

CC ID: 686606
Date Effective From: 2005-04-06
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202


CC ID: 686608
Date Effective From: 2005-04-06
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202

Metadata Contact

CC ID: 686609
Date Effective From: 2005-04-06
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202

Point of Contact

CC ID: 686607
Date Effective From: 2005-04-06
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202


Currentness Reference: Ground Condition

Extent Group 1

Extent Group 1 / Geographic Area 1

CC ID: 1138096
W° Bound: -118.209205
E° Bound: -117.122305
N° Bound: 33.768577
S° Bound: 32.549177

Extent Group 1 / Time Frame 1

CC ID: 1138095
Time Frame Type: Range
Start: 2004-09-28
End: 2004-09-30

Spatial Information

Spatial Representation

Representations Used

Vector: Yes

Access Information

Security Class: Unclassified
Data Access Procedure:

This data can be obtained on-line at the following URL:


Data Access Constraints:


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: 742572
Download URL:
File Name: Customized Download

Create custom data files by choosing data area, product type, map projection, file format, datum, etc.

Distribution 2

CC ID: 742573
Download URL:
File Name: Bulk Download

Simple download of data files.



CC ID: 742575
URL Type:
Online Resource


CC ID: 742576
URL Type:
Online Resource

Activity Log

Activity Log 1

CC ID: 686630
Activity Date/Time: 2016-05-23

Date that the source FGDC record was last modified.

Activity Log 2

CC ID: 686629
Activity Date/Time: 2017-11-14

Converted from FGDC Content Standards for Digital Geospatial Metadata (version FGDC-STD-001-1998) using '' script. Contact Tyler Christensen (NOS) for details.

Activity Log 3

CC ID: 718608
Activity Date/Time: 2018-02-08

Partial upload of Positional Accuracy fields only.

Activity Log 4

CC ID: 742574
Activity Date/Time: 2018-03-13

Partial upload to move data access links to Distribution Info.

Data Quality

Horizontal Positional Accuracy:

Selected portions from each lidar data set (last return only) were used to generate

a 1m x 1m digital elevation model (DEM). Data estimated to have a horizontal accuracy of 0.01-0.03m from ground surveys

using kinematic GPS techniques were superimposed on the lidar DEM and examined for any mismatch between the horizontal

position of the ground GPS and the corresponding feature on the lidar DEM. Horizontal agreement between the ground kinematic

GPS and the lidar was within the resolution of the 1m x 1m DEM.

Vertical Positional Accuracy:

The September 2004 lidar data were compared to the 1998 ATM LIDAR data to determine

offsets in the vertical position. The ATM survey points are estimated to have a vertical accuracy of +/- 15 cm. The September

2004 lidar data set was sorted to find data points that fell within 0.5 m of an ATM LIDAR survey point along piers in the

survey area. The mean elevation difference between the September 2004 survey and the ATM survey was used to estimate and

remove an elevation bias from the lidar. The standard deviation of these elevation differences provides estimates of the

lidar precision. The bias was removed so that mean lidar elevations have a vertical accuracy of 0.10 m.

Completeness Report:

Data were edited by an automated method to remove obvious outliers above a threshold of 150m.

Conceptual Consistency:

Not Applicable



Air and Ground GPS files from 27204, 27304, and 27404

CC ID: 1138089
Publish Date: 2004-09-30
Extent Type: Range
Extent Start Date/Time: 2004-09-28
Extent End Date/Time: 2004-09-30
Source Contribution:

air and ground GPS files

base station coordinates Easting, Northing, HAE in NAD83 (Latitude, Longitude):

Seal Beach (SEAL) = 399190.247, 3733584.001, -27.236 (N 33 44 15.03645, W 118 5 17.77081)

Dana Point (DANA) = 434088.756, 3702981.864, 52.914 (N 33 27 51.33986, W 117 42 33.47697)

Point Loma (LOMA) = 477399.618, 3614791.239, 90.892 (N 32 40 13.99715, W 117 14 27.74755)

| Type of Source Media: digital file

Raw lidar data output from ALTM 1225

CC ID: 1138090
Publish Date: 2004-09-30
Extent Type: Range
Extent Start Date/Time: 2004-09-28
Extent End Date/Time: 2004-09-30
Source Contribution:

raw lidar data from ALTM 1225 (all times UTC)


Pass A (Oceanside to La Jolla) = 21:59-22:11

Pass B (La Jolla to Dana Point) = 22:36-23:01

Pass C (Dana Point to Del Mar) = 23:05-23:33

Pass D (Del Mar to Dana Point) = 23:39-23:58

Pass E (Dana Point to San Onofre) = 00:01-00:07

Calibration Passes = 22:14-22:30


Pass A (Oceanside to Mexico) = 20:52-21:17

Pass B (Mexico to Point Loma) = 21:23-21:29

Pass C (Mexico to La Jolla) = 21:36-21:52

Pass D (La Jolla to Newport) = 22:10-22:45

Pass E (Newport to Carlsbad = 22:48-23:13

Calibration Passes = 21:55-22:07


Pass A (Dana Point to Long Beach) = 21:02-21:19

Pass B (Long Beach to Dana Point) = 21:20-21:38

Pass C (Dana Point to Long Beach) = 21:40-21:57

Pass D (Long Beach to Dana Point) = 21:58-22:10 and 22:22-22:27

Calibration Passes = 22:12-22:20

| Type of Source Media: digital file

Process Steps

Process Step 1

CC ID: 1138091

GPS and XYZ-Point Data Processing

The National Geodetic Survey's PAGES-NT software was used to compute double differenced, ionospherically corrected,

static GPS solutions for each GPS base station with precise ephemeredes from the International GPS Service (IGS). As part

of the solution tropospheric zenith delays were estimated and L1 and L2 phase biases were fixed as integers.

Aircraft trajectories were estimated with respect to all base stations using National Geodetic Survey's Kinematic and

Rapid-Static Software (KARS) software. Trajectories were double-differenced, ionospherically corrected, bias-fixed GPS

solutions computed with precise IGS ephemeredes. Coordinates for base stations and trajectories were in the International

Terrestrial Reference Frame of 2000 (ITRF00). The aircraft trajectory were transformed from the ITRF00 to North American

Datum of 1983 (NAD83) using the Horizontal Time Dependent Positioning (HDTP) software (Snay, 1999)

The 1Hz GPS trajectory and 50Hz aircraft inertial measurement unit (IMU) data were combined in Applanix's POSProc version

2.1.4 to compute an aided inertial navigation solution (INS) and a 50Hz, smoothed best estimate of trajectory (SBET).

The SBET, laser range observations, scanner position information, and GPS/internal clock files were processed in Realm

2.27 software suite to generate lidar data points in the Universal Transverse Mercator (UTM) projection.

Lidar point data were compared to GPS ground survey data and 1998 ATM lidar data to estimate lidar instrument calibration

parameters: roll and pitch biases, scanner scale factor, and first/last return elevation biases. An iterative,

least-squares methodology was used to estimate calibration parameters so as to minimize differences between lidar and ground GPS data.

Samples of lidar data were used to create high-resolution digital elevation models (DEM); these DEM were inspected for

horizontal or vertical anomalies.

After system calibration and initial quality control step, the adjusted lidar x,y,z-point data were generated by REALM

software and output, by shoreline pass, in UTM Zone 11 with elevations being heights above the GRS-80 reference ellipsoid (HAE).

The output format from REALM 2.27 was a 9-column ASCII file containing: the second in the GPS week, easting, northing and HAE

of the first lidar return, the easting, northing and HAE of the last lidar return, and the laser backscatter intensity of

the first and last returns.

Using the GEOID99 geoid model, heights above the GRS80 ellipsoid were converted to orthometric heights with respect to

the North American Vertical Datum of 1988 (NAVD88). Parse the 9-column lidar point file into 3.75-minute quarter-quadrangle

components. Convert UTM Easting and Northing to geodetic latitude and longitude with respect to the GRS80 ellipsoid.

The conversion was computed using the TMGEOD and TCONPC fortran subroutines written by T. Vincenty (NGS). Each record contains

9 columns of data: time tag (seconds in the GPS week), first return Latitude, first return Longitude, first return NAVD88,

last return Latitude, last return Longitude, last return NAVD88, first return intensity, and last return intensity.

In some cases either the first or last return values may be missing (5 columns). Latitude and longitude are in decimal

degrees with nine significant digits to retain the 0.01m resolution of the UTM coordinates. West longitude is negative

and north latitude is positive. The UTM quarter-quad files were re-organized into latitude delineated files.

UTM quarter-quads files that were delineated by the same upper and lower latitude bounds were concatenated.

The lat-long files were named by the month-year of the survey (e.g. sep04) and the lower latitude bounding the quarter-quad.

Processing occurred 20040928-20050406.

Process Date/Time: 2004-09-28 00:00:00

Process Step 2

CC ID: 1138092

Created initial metadata

Process Date/Time: 2003-04-18 00:00:00

Process Step 3

CC ID: 1138093

The NOAA Office for Coastal Management (OCM) received files in ASCII format. The files contained LiDAR intensity

and elevation measurements. OCM performed the following

processing on the data to make it available within the LiDAR Data Retrieval Tool (LDART)

1. Data returned to ellipsoid heights from NAVD88, using GEOID99.

2. Data converted to LAS format.

3. The LAS data were sorted by latitude and the headers were updated.

Process Date/Time: 2007-07-24 00:00:00

Catalog Details

Catalog Item ID: 50007
GUID: gov.noaa.nmfs.inport:50007
Metadata Record Created By: Anne Ball
Metadata Record Created: 2017-11-15 15:23+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2022-08-09 17:11+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